The document discusses the manufacturing process of staple or spun yarn, describing the various processes involved from blow room to ring spinning that transform raw cotton fibers into yarn. It provides an overview of each processing stage including blow room, carding, combing, drawing, roving, and ring spinning. The goal is to produce clean, strong, and uniform yarns through these continuous operations of opening, blending, mixing, cleaning, carding, drawing, roving and spinning.
This document is an assignment submission for a course on testing textiles. It describes an experiment conducted on a Yarn Lea Strength Tester to determine the strength of a cotton yarn sample. The experiment found that the yarn strength was 79.32 lbs/lea and the Count Strength Product (CSP) was 2379.6. Since the CSP was greater than the standard of 2200, the document concludes that the yarn sample had good strength fibers.
Pierce's model treats woven fabric as a repeating network of identical unit cells composed of interlacing yarns with circular cross-sections. It allows for calculation of geometric parameters like thread spacing and fabric thickness. Kemp's model modifies yarn cross-section to an elliptical racetrack shape to better model tightly woven fabrics. Hearle's lenticular model uses an energy approach. While these models provide simplified representations, real fabrics do not conform to idealized shapes and the relationship between geometry and mechanical properties is still not fully understood.
End breakage at ring frame. Ring frame machine breakageMukulpratapHarijan
End breakage at ring frame thier causes and solution. Effect of end breakage. Ring frame breakage. Fault of end breakage. PPT and PDF of end breakage. Solution of less efficiency of ring frame machine
Analysis of rejected ring cops in autoconer winding machineTaukir Kabir Tusar
This document discusses the analysis of rejected ring cops in an autoconer winding machine. It begins with an introduction that describes ring cops, rejected ring cops, and the aim of analyzing the causes of cop rejections. The document then covers literature related to winding, common faults in winding, and reasons for faulty ring cops being rejected. It describes the experimental work, including collecting sample cops, quality tests performed, and identified causes of rejection such as count variation, product type variation, low cop content, and excessive neps. The goal is to understand the sources of rejections in order to reduce rejection rates.
This presentation summarizes the important parts of a ring frame machine. It discusses the main operations of the ring frame as creeling, drafting, twisting, winding and doffing. It then describes the main parts of the ring frame such as the roving bobbin, roving, creel, guide rail, drafting arrangement, yarn, yarn guide, spindle, traveler and ring. Diagrams are included to illustrate the condenser, apron, ring and traveler, spindle and lappet. The presentation provides an overview of the key components and processes involved in ring frame spinning.
The document summarizes the working principle and components of a carding machine. It describes the key zones - feed roller taker-in zone, taker-in cylinder zone, cylinder-flat zone, and cylinder-doffer zone. It explains the stripping, carding, and doffing actions that take place between different components to open, clean, and form fibers into a web. Characteristics of card sliver and factors that affect card clothing effectiveness are also summarized.
This document discusses different types of yarn faults, including:
1. Yarn content in the cop being less, causing efficiency loss and more knots. This can be caused by underutilization of bobbin height or improper ratchet settings.
2. Slubs, which are thick lumps showing less twist. This can damage fabrics and cause shade variations. Poor carding, machine dirtiness, and drafting issues can cause slubs.
3. Neps, which are rolled fiber masses visible on black boards. This also damages fabrics. Machine cleaning, carding, and drafting are important to prevent neps.
Roving Frame is machine of Spinning section.
The roving frame is an intermediate engine between draw frame and ring frame. Main objective of this machine is to change sliver in to thinner sliver for the convenience of subsequent processes. The sliver we get from draw frame is still thicker sliver which is not good for yarn manufacture.
This document is an assignment submission for a course on testing textiles. It describes an experiment conducted on a Yarn Lea Strength Tester to determine the strength of a cotton yarn sample. The experiment found that the yarn strength was 79.32 lbs/lea and the Count Strength Product (CSP) was 2379.6. Since the CSP was greater than the standard of 2200, the document concludes that the yarn sample had good strength fibers.
Pierce's model treats woven fabric as a repeating network of identical unit cells composed of interlacing yarns with circular cross-sections. It allows for calculation of geometric parameters like thread spacing and fabric thickness. Kemp's model modifies yarn cross-section to an elliptical racetrack shape to better model tightly woven fabrics. Hearle's lenticular model uses an energy approach. While these models provide simplified representations, real fabrics do not conform to idealized shapes and the relationship between geometry and mechanical properties is still not fully understood.
End breakage at ring frame. Ring frame machine breakageMukulpratapHarijan
End breakage at ring frame thier causes and solution. Effect of end breakage. Ring frame breakage. Fault of end breakage. PPT and PDF of end breakage. Solution of less efficiency of ring frame machine
Analysis of rejected ring cops in autoconer winding machineTaukir Kabir Tusar
This document discusses the analysis of rejected ring cops in an autoconer winding machine. It begins with an introduction that describes ring cops, rejected ring cops, and the aim of analyzing the causes of cop rejections. The document then covers literature related to winding, common faults in winding, and reasons for faulty ring cops being rejected. It describes the experimental work, including collecting sample cops, quality tests performed, and identified causes of rejection such as count variation, product type variation, low cop content, and excessive neps. The goal is to understand the sources of rejections in order to reduce rejection rates.
This presentation summarizes the important parts of a ring frame machine. It discusses the main operations of the ring frame as creeling, drafting, twisting, winding and doffing. It then describes the main parts of the ring frame such as the roving bobbin, roving, creel, guide rail, drafting arrangement, yarn, yarn guide, spindle, traveler and ring. Diagrams are included to illustrate the condenser, apron, ring and traveler, spindle and lappet. The presentation provides an overview of the key components and processes involved in ring frame spinning.
The document summarizes the working principle and components of a carding machine. It describes the key zones - feed roller taker-in zone, taker-in cylinder zone, cylinder-flat zone, and cylinder-doffer zone. It explains the stripping, carding, and doffing actions that take place between different components to open, clean, and form fibers into a web. Characteristics of card sliver and factors that affect card clothing effectiveness are also summarized.
This document discusses different types of yarn faults, including:
1. Yarn content in the cop being less, causing efficiency loss and more knots. This can be caused by underutilization of bobbin height or improper ratchet settings.
2. Slubs, which are thick lumps showing less twist. This can damage fabrics and cause shade variations. Poor carding, machine dirtiness, and drafting issues can cause slubs.
3. Neps, which are rolled fiber masses visible on black boards. This also damages fabrics. Machine cleaning, carding, and drafting are important to prevent neps.
Roving Frame is machine of Spinning section.
The roving frame is an intermediate engine between draw frame and ring frame. Main objective of this machine is to change sliver in to thinner sliver for the convenience of subsequent processes. The sliver we get from draw frame is still thicker sliver which is not good for yarn manufacture.
This document discusses positive yarn feeding systems and how they affect fabric quality. It provides information on different types of positive yarn feeding systems including tape feed mechanisms and storage feeders. Positive yarn feeding helps control fabric properties and quality by providing uniform yarn tension and detecting faults before knitting. Modern systems use microprocessors and pre-calculated yarn requirements to precisely control yarn delivery. While positive feeding improves quality, it can also cause yarn breakage issues which manufacturers work to overcome through innovations like ceramic coated feed wheels.
This document discusses different types of weaving machines, including multiphase weaving machines. It describes wave shed and parallel shed multiphase looms. Wave shed looms have shuttles that travel in straight or circular paths, while parallel shed looms form successive parallel sheds across the warp. The fastest weaving machine is the Sulzer M8300 multiphase loom, which can produce up to 1500 meters of fabric per day at a production cost 25-30% lower than single phase looms.
This document provides information about fancy yarns from Amsler Tex. It defines fancy yarn as having varied characteristics like thickness, color, and raw material that give fabrics a unique aesthetic. It then lists and describes different types of fancy yarns that can be produced using Amsler devices, including slub yarn, multi-count yarn, and multi-twist yarn. The document also explains concepts like the working principles of drafting and twisting systems, yarn measurement, effect coding, and how to simulate fabrics digitally before production.
Drafting is the creation of a drawing or other graphical representation of a building, mechanical device or other structure for the purposes of determining how the device should be created. Drafting is used as a part of the design and fabrication processes. Drafting can be done by hand or using specially designed computer programs and mechanical drawings.
Drafting arrangement is the most important part of the machine. It influences mainly evenness and strength The following points are therefore very important
This document compares ring spinning and rotor spinning methods of yarn formation. It discusses that rotor spinning is a more recent method that omits the step of forming a roving. In rotor spinning, fibers are fed into a rotary beater and deposited onto the sides of a rotating disc called a rotor, where they are twisted without requiring package rotation. Rotor spinning allows for higher twisting speeds with lower power usage compared to ring spinning. It provides characteristics like higher productivity, larger sliver/package sizes, less power consumption, and more automation/flexibility. The document provides details on the parts of a rotor spinning machine and compares various parameters of ring-spun and rotor-spun yarns.
This document discusses various methods for measuring fibre length in textile materials like cotton and wool. It describes parameters used to characterize fibre length such as staple length, mean length, upper quartile length, and dispersion percentage. Methods covered include hand stapling, Shirley photoelectric stapler, comb sorter, weighing and clamping techniques, and optical methods using fibrographs and capacitive instruments like the Almeter. The document provides detailed explanations of each parameter and measurement technique.
The document discusses the carding process which involves opening, cleaning and assembling fibers into a sliver through different sections of a carding machine like feed, licker-in, cylinder and doffer. It explains the objectives, necessities and zones of carding along with details of components like types of clothing, their functioning and settings that are important for quality carding. The document also covers developments in carding technology and types of drives used in modern carding machines.
Opening in blow room means opening into small flocks. Technological operation of opening means the volume of the flock is increased while the number of fibres remains constant
startup breakages in ring frame and their controlVicky Raj
This document discusses start up breakages on ring spinning frames and methods to control them. It defines start up breakages as thread breaks that occur after starting the machine or after doffing bobbins. Potential causes include issues with drafting timing, back winding, under winding, traveller settings, doffing practices, start speed, suction, gear meshing, undrafted material, and more. Methods are provided to measure start up breakage percentage and suggestions for remedies like changing travelers periodically, adjusting ring and spindle settings, checking material quality, and optimizing climate and cleaning procedures.
This document presents information about ring spinning. Md. Yousuf Hossain from Green University of Bangladesh introduces the topic and defines key terms like fiber, spinning and yarn. It then describes the ring spinning process which involves blow room, carding, draw frame and speed frame before the roving reaches the ring frame. Here, it is drafted and twisted to produce yarn, which is then wound onto bobbins. The document focuses on the drafting zone of the ring frame and explains how higher drafts are applied. It also provides details about how the yarn travels through the traveller and onto the cop during winding. In closing, advantages and limitations of ring spinning are mentioned.
importance of fibre finess,influences of fibre finess ,effect on stiffness , effect on torsional rigidity, reflection of light , dye absoprtion, method of measurement ,gravimetric method, micronaire
Differents parts of Simplex Machine and their FunctionsSadia Textile
The fly frame takes the thicker draw sliver and drafts, twists, and winds it into a thinner roving package. It attenuates the sliver through multiple drafting rollers that increase in speed, which stretches and thins the material. A flyer inserts twist into the roving to hold the fibers together. The key components of the fly frame are the creel, drafting rollers, flyer, spindles, and winding components. Modern fly frames like the Toyoda FL-100 and FL-200 use servo motor systems for more precise control compared to earlier cone drive systems.
A roving frame produces rovings of cotton and synthetic fibers through a process of drafting, twisting, and winding. It attenuates sliver through multiple drafting zones to form rovings of the required count. A flyer inserts twist into the roving as it is wound onto bobbins. Modern roving frames can achieve higher production rates through increased flyer speeds up to 1400 rpm and delivery speeds up to 40 m/min. They also have improved drafting systems and flyer designs for better fiber control and a wider draft range.
This document discusses the rapier loom and rapier weaving. It begins by defining a rapier loom as one that uses a rapier to pull the weft yarn across the loom. It can use a single or double rapier system. It then describes the key components and functioning of single and double rigid and flexible rapier systems. It also discusses different weft insertion principles like Dewas and Gabler systems as well as rapier drives, features of modern rapier looms, selvedge formation, weft insertion rates, and equations for calculating weaving production rates.
This document discusses the rotor spinning process. It begins by describing the basic principle of open-end yarn formation and the different types of open-end spinning processes. It then provides details on the specific features, principles, and settings of rotor spinning machines. This includes descriptions of the feed, sliver opening, fiber transport, yarn formation, and winding processes. It discusses the raw material requirements and preparation for rotor spinning. Overall, the document provides a comprehensive overview of the rotor spinning process from fiber preparation through yarn formation and winding.
The document discusses the roving frame machine, which comes after the draw frame in the spinning process. The roving frame drafts sliver from draw frame cans into a thin roving strand and applies a light twist. It operates by drafting the sliver, guiding it through the flyer to apply twist, and winding the roved strand onto bobbins. While complicated, the roving frame produces packages of roving suitable for input to the ring frame. Efforts to eliminate this step have not succeeded due to the high drafts required in ring frames.
Warp knitting is a family of knitting methods in which the yarn zigzags along the length of the fabric, i.e., following adjacent columns ("wales") of knitting, rather than a single row ("course"). For comparison, knitting across the width of the fabric is called weft knitting
This document discusses jammed fabric structures and provides mathematical models to predict their properties. A jammed fabric is one where the warp and weft yarns are in intimate contact with no mobility between yarns. Pierce's model and the racetrack model are presented to calculate thread spacing, fabric cover, and crimp based on yarn diameters. A truly square jammed fabric has equal warp and weft spacing, crimp, and angles. Such a fabric has 20.9% crimp and cover factors of 16.2. Jammed fabrics are closely woven and used for waterproof, windproof and bulletproof applications.
The document discusses the operation of the carding machine, which is considered the "heart" of the spinning mill. It describes the key tasks of the carding machine, including opening fibers into individual strands, removing impurities, disentangling neps, and forming sliver for further processing. The operating principle is explained, with details provided on the material feed, licker-in, main cylinder, flats, doffer, and sliver formation processes. Different carding machine designs are also summarized, such as variations in the card chute and feed device configurations.
Rapier weaving is a shuttleless weaving technique where rigid or flexible rapiers carry the weft yarn through the shed. There are single and double rapier systems, with double being more common. In double systems, one rapier (giver) brings the yarn to the center and transfers it to the other rapier (taker) to carry to the other side. Dewas and Gabler systems differ in how the transfer occurs. Rapier machines are versatile and efficient with minimal stress on the weft yarn, resulting in high quality fabrics and low yarn breakage. Factors like machine speed, yarn properties, and shed formation affect yarn stresses.
This document provides information about various yarn defects seen in ring spinning, their causes, effects, and methods for rectification. It describes 18 different types of defects like slubs, neps, thin places, kinks, thick places, etc. For each defect, it mentions the potential effects on subsequent processes and the fabric, likely causes related to machine settings or raw material issues, and recommended actions to address the problem. The goal is to help spinning mill staff properly identify and troubleshoot quality issues.
Importance, Effect & Testing of Yarn EvennessAmirul Eahsan
This document discusses irregularity or unevenness of fiber, which refers to variations in mass per unit length of a fiber assembly. It describes two common methods for measuring irregularity - the irregularity U% and the coefficient of variation C.V%. Several methods for measuring fiber irregularity are outlined, including visual inspection, cutting and weighing, and various testing machines like the Uster Evenness Tester and photoelectric testers. Irregular fibers can affect yarn strength, fabric appearance, and dyeing/finishing. Maintaining low irregularity is important for quality control in textile production.
This document discusses positive yarn feeding systems and how they affect fabric quality. It provides information on different types of positive yarn feeding systems including tape feed mechanisms and storage feeders. Positive yarn feeding helps control fabric properties and quality by providing uniform yarn tension and detecting faults before knitting. Modern systems use microprocessors and pre-calculated yarn requirements to precisely control yarn delivery. While positive feeding improves quality, it can also cause yarn breakage issues which manufacturers work to overcome through innovations like ceramic coated feed wheels.
This document discusses different types of weaving machines, including multiphase weaving machines. It describes wave shed and parallel shed multiphase looms. Wave shed looms have shuttles that travel in straight or circular paths, while parallel shed looms form successive parallel sheds across the warp. The fastest weaving machine is the Sulzer M8300 multiphase loom, which can produce up to 1500 meters of fabric per day at a production cost 25-30% lower than single phase looms.
This document provides information about fancy yarns from Amsler Tex. It defines fancy yarn as having varied characteristics like thickness, color, and raw material that give fabrics a unique aesthetic. It then lists and describes different types of fancy yarns that can be produced using Amsler devices, including slub yarn, multi-count yarn, and multi-twist yarn. The document also explains concepts like the working principles of drafting and twisting systems, yarn measurement, effect coding, and how to simulate fabrics digitally before production.
Drafting is the creation of a drawing or other graphical representation of a building, mechanical device or other structure for the purposes of determining how the device should be created. Drafting is used as a part of the design and fabrication processes. Drafting can be done by hand or using specially designed computer programs and mechanical drawings.
Drafting arrangement is the most important part of the machine. It influences mainly evenness and strength The following points are therefore very important
This document compares ring spinning and rotor spinning methods of yarn formation. It discusses that rotor spinning is a more recent method that omits the step of forming a roving. In rotor spinning, fibers are fed into a rotary beater and deposited onto the sides of a rotating disc called a rotor, where they are twisted without requiring package rotation. Rotor spinning allows for higher twisting speeds with lower power usage compared to ring spinning. It provides characteristics like higher productivity, larger sliver/package sizes, less power consumption, and more automation/flexibility. The document provides details on the parts of a rotor spinning machine and compares various parameters of ring-spun and rotor-spun yarns.
This document discusses various methods for measuring fibre length in textile materials like cotton and wool. It describes parameters used to characterize fibre length such as staple length, mean length, upper quartile length, and dispersion percentage. Methods covered include hand stapling, Shirley photoelectric stapler, comb sorter, weighing and clamping techniques, and optical methods using fibrographs and capacitive instruments like the Almeter. The document provides detailed explanations of each parameter and measurement technique.
The document discusses the carding process which involves opening, cleaning and assembling fibers into a sliver through different sections of a carding machine like feed, licker-in, cylinder and doffer. It explains the objectives, necessities and zones of carding along with details of components like types of clothing, their functioning and settings that are important for quality carding. The document also covers developments in carding technology and types of drives used in modern carding machines.
Opening in blow room means opening into small flocks. Technological operation of opening means the volume of the flock is increased while the number of fibres remains constant
startup breakages in ring frame and their controlVicky Raj
This document discusses start up breakages on ring spinning frames and methods to control them. It defines start up breakages as thread breaks that occur after starting the machine or after doffing bobbins. Potential causes include issues with drafting timing, back winding, under winding, traveller settings, doffing practices, start speed, suction, gear meshing, undrafted material, and more. Methods are provided to measure start up breakage percentage and suggestions for remedies like changing travelers periodically, adjusting ring and spindle settings, checking material quality, and optimizing climate and cleaning procedures.
This document presents information about ring spinning. Md. Yousuf Hossain from Green University of Bangladesh introduces the topic and defines key terms like fiber, spinning and yarn. It then describes the ring spinning process which involves blow room, carding, draw frame and speed frame before the roving reaches the ring frame. Here, it is drafted and twisted to produce yarn, which is then wound onto bobbins. The document focuses on the drafting zone of the ring frame and explains how higher drafts are applied. It also provides details about how the yarn travels through the traveller and onto the cop during winding. In closing, advantages and limitations of ring spinning are mentioned.
importance of fibre finess,influences of fibre finess ,effect on stiffness , effect on torsional rigidity, reflection of light , dye absoprtion, method of measurement ,gravimetric method, micronaire
Differents parts of Simplex Machine and their FunctionsSadia Textile
The fly frame takes the thicker draw sliver and drafts, twists, and winds it into a thinner roving package. It attenuates the sliver through multiple drafting rollers that increase in speed, which stretches and thins the material. A flyer inserts twist into the roving to hold the fibers together. The key components of the fly frame are the creel, drafting rollers, flyer, spindles, and winding components. Modern fly frames like the Toyoda FL-100 and FL-200 use servo motor systems for more precise control compared to earlier cone drive systems.
A roving frame produces rovings of cotton and synthetic fibers through a process of drafting, twisting, and winding. It attenuates sliver through multiple drafting zones to form rovings of the required count. A flyer inserts twist into the roving as it is wound onto bobbins. Modern roving frames can achieve higher production rates through increased flyer speeds up to 1400 rpm and delivery speeds up to 40 m/min. They also have improved drafting systems and flyer designs for better fiber control and a wider draft range.
This document discusses the rapier loom and rapier weaving. It begins by defining a rapier loom as one that uses a rapier to pull the weft yarn across the loom. It can use a single or double rapier system. It then describes the key components and functioning of single and double rigid and flexible rapier systems. It also discusses different weft insertion principles like Dewas and Gabler systems as well as rapier drives, features of modern rapier looms, selvedge formation, weft insertion rates, and equations for calculating weaving production rates.
This document discusses the rotor spinning process. It begins by describing the basic principle of open-end yarn formation and the different types of open-end spinning processes. It then provides details on the specific features, principles, and settings of rotor spinning machines. This includes descriptions of the feed, sliver opening, fiber transport, yarn formation, and winding processes. It discusses the raw material requirements and preparation for rotor spinning. Overall, the document provides a comprehensive overview of the rotor spinning process from fiber preparation through yarn formation and winding.
The document discusses the roving frame machine, which comes after the draw frame in the spinning process. The roving frame drafts sliver from draw frame cans into a thin roving strand and applies a light twist. It operates by drafting the sliver, guiding it through the flyer to apply twist, and winding the roved strand onto bobbins. While complicated, the roving frame produces packages of roving suitable for input to the ring frame. Efforts to eliminate this step have not succeeded due to the high drafts required in ring frames.
Warp knitting is a family of knitting methods in which the yarn zigzags along the length of the fabric, i.e., following adjacent columns ("wales") of knitting, rather than a single row ("course"). For comparison, knitting across the width of the fabric is called weft knitting
This document discusses jammed fabric structures and provides mathematical models to predict their properties. A jammed fabric is one where the warp and weft yarns are in intimate contact with no mobility between yarns. Pierce's model and the racetrack model are presented to calculate thread spacing, fabric cover, and crimp based on yarn diameters. A truly square jammed fabric has equal warp and weft spacing, crimp, and angles. Such a fabric has 20.9% crimp and cover factors of 16.2. Jammed fabrics are closely woven and used for waterproof, windproof and bulletproof applications.
The document discusses the operation of the carding machine, which is considered the "heart" of the spinning mill. It describes the key tasks of the carding machine, including opening fibers into individual strands, removing impurities, disentangling neps, and forming sliver for further processing. The operating principle is explained, with details provided on the material feed, licker-in, main cylinder, flats, doffer, and sliver formation processes. Different carding machine designs are also summarized, such as variations in the card chute and feed device configurations.
Rapier weaving is a shuttleless weaving technique where rigid or flexible rapiers carry the weft yarn through the shed. There are single and double rapier systems, with double being more common. In double systems, one rapier (giver) brings the yarn to the center and transfers it to the other rapier (taker) to carry to the other side. Dewas and Gabler systems differ in how the transfer occurs. Rapier machines are versatile and efficient with minimal stress on the weft yarn, resulting in high quality fabrics and low yarn breakage. Factors like machine speed, yarn properties, and shed formation affect yarn stresses.
This document provides information about various yarn defects seen in ring spinning, their causes, effects, and methods for rectification. It describes 18 different types of defects like slubs, neps, thin places, kinks, thick places, etc. For each defect, it mentions the potential effects on subsequent processes and the fabric, likely causes related to machine settings or raw material issues, and recommended actions to address the problem. The goal is to help spinning mill staff properly identify and troubleshoot quality issues.
Importance, Effect & Testing of Yarn EvennessAmirul Eahsan
This document discusses irregularity or unevenness of fiber, which refers to variations in mass per unit length of a fiber assembly. It describes two common methods for measuring irregularity - the irregularity U% and the coefficient of variation C.V%. Several methods for measuring fiber irregularity are outlined, including visual inspection, cutting and weighing, and various testing machines like the Uster Evenness Tester and photoelectric testers. Irregular fibers can affect yarn strength, fabric appearance, and dyeing/finishing. Maintaining low irregularity is important for quality control in textile production.
Knowing the basics of raw material, yarn production process and the other factors influencing quality will put the sourcing manager at the same eye level as a spinner /supplier when negotiating quality issues.
As a consequence this puts the sourcing manager in the position to pay the right price for the corresponding quality level.
This kind of know-how supports a retailer enormously in his efforts to establish a reliable supply chain which is based on mutual understanding.
Hairiness is characterized by the quantity of freely moving fibre ends or fibre loops projecting from a yarn or textile fabric (woven, knitted or non woven fabrics).
In term of measurement Hairiness corresponds to the total length of the protruding fibres in unit length of one centimeter.
1.5 kg/kg of sized yarn
This document provides information on textile calculations related to fibre fineness, yarn counts, conversions, and production calculations for various textile processes. Some key points include:
- Micronaire value, denier, and micron are units used to measure fibre fineness for cotton, man-made fibers, and wool respectively.
- There are indirect and direct systems for classifying yarn counts including English, French, metric, worsted, and tex/denier systems.
- Formulas are provided for calculating production rates for processes like blowroom, carding, drawframe, speedframe, ringframe, winding, and s
This document provides information about measuring moisture in textile materials and various related calculations. It lists the standard moisture regain for different materials like cotton, wool, viscose, silk, and jute. It also defines terms like absolute humidity, relative humidity, original weight, dry weight, oven dry weight, correct invoice weight, regain, and moisture content. The document includes examples of calculations for moisture content, regain, conditioned count weight, blending and mixing of materials, and piping diameters.
The document discusses yarn hairiness, which is an undesirable property that deteriorates fabric appearance. Higher hairiness can be caused by raw material issues like immature cotton fibers or improper micronaire value, processing problems like inadequate drafting, or maintenance issues on spinning machines.
Three common hairiness testers are described: the Uster Tester 3 uses light scattering to measure total hairiness; the Shirley Yarn Hairiness Tester counts interruptions in a light beam as individual hairs pass through; and the Zweigle Hairiness Tester G565 counts hairs at different distances from the yarn edge using photocells.
Yarn unevenness and its empact on qualityArNesto WaHid
This document discusses yarn unevenness, its causes, measurement, and impact on quality. Yarn unevenness refers to variations in yarn thickness along its length. It is influenced by raw material variations and spinning process irregularities. Unevenness is measured using the irregularity percentage and coefficient of variation. Higher unevenness can reduce yarn strength, impact fabric appearance with defects, and lower productivity. Careful control of the spinning process is needed to minimize unevenness and maximize quality.
This document is a report by Enquzer Getachew on their internship at Ayka Addis Textile and Investment Group from October 20, 2010 to February 7, 2011. It provides an overview of the textile processes at Ayka, including spinning (blow room, carding, drawing, roving), knitting, and dyeing. It describes the equipment and processes in each department and identifies some problems observed along with recommendations. The report is intended to provide information on textile machinery and processes gained from their education and experience during the internship.
The document discusses yarn twist, which is the spiral arrangement of fibers that binds them together and contributes to yarn strength. It defines twist, describes different types of twist including real and false twist. It also discusses factors that affect twist, methods of measuring and expressing twist, and the effects of twist on yarn and fabric properties such as handle, moisture absorption, and wearing properties. High twist results in a harder handle, better abrasion resistance, and lower moisture absorption, while low twist produces a softer feel but weaker yarn.
The document discusses various concepts related to spinning calculations including:
1) It describes two systems for measuring yarn count - direct and indirect. The direct system measures weight per unit length while the indirect measures length per unit weight.
2) It provides formulas for calculating yarn production rates for various machines like scutchers, cards, draw frames, and ring frames. The key factors are roller diameter, rpm, yarn count, efficiency, and number of machines/spindles.
3) It defines terms like hank, twists per inch, beats per inch, efficiency, and provides conversions between different units of measurement.
Textile yarn manufacturing involves several key steps. Fibers are first opened and cleaned through blowroom and carding processes. Drawing further arranges fibers into parallel strands called slivers. Roving attenuates slivers and adds twist. Ring frames then spin roving into yarn using drafts and twist. Combing upgrades raw materials by removing short fibers. The processes work to arrange, draft, and twist fibers into consistent yarns for weaving or other uses.
Meeting the Customer expectations on Yarn Quality is the topmost priority of the profitable spinning mills.WINSYS SMC explains the same alongwith Customer satisfaction measures.
Achieving Manufacturing Excellence in Spinning mills through Productivity benchmarking is explained through reference standards and case studies by WINSYS SMC.
Spectrograms allow phoneticians to visualize how the frequency spectrum of speech sounds changes over time. They plot frequency on the vertical axis, time on the horizontal axis, and intensity as color. Narrowband spectrograms provide detailed frequency information while wideband spectrograms precisely show timing. Common speech sounds like vowels, consonants, and transitions between them exhibit characteristic patterns. Reading spectrograms is essential for instrumental phonetics research.
The document discusses electronic yarn clearers and how to set their settings systematically. It describes the two main principles that electronic yarn clearers use - optical and capacitive measuring. It also classifies different types of yarn defects and discusses how to determine the appropriate settings based on the desired yarn quality, productivity, and customer requirements. The key steps are to test the yarn over long distances, analyze defect levels, and adjust the clearing curve settings to achieve the target quality levels.
This document is a thesis submitted by eight students from Cranfield University in partial fulfillment of their MSc in Offshore and Ocean Technology. It examines options for a low cost subsea processing system for brownfield developments. The students analyze existing subsea processing technologies, propose two system configuration options, and select a three-phase gravity separator system. They design a three-phase gravity separator through numerical simulation and analysis of field data from the Balmoral field in the UK. The proposed system includes a three-phase separator, oil and gas boosting pumps, and a water reinjection pump.
This document summarizes the design and construction of a variable geometry, supersonic wind tunnel by a group of WPI students. It provides background on supersonic wind tunnel design using the method of characteristics. It then describes the initial calculations performed to determine design constraints. The key features of the designed tunnel include flexible polystyrene contours to allow achieving various test section Mach numbers and adjustable mechanisms to control the throat, expansion, and diffuser sections. Construction of the tunnel was not fully completed within the project timeframe.
This document outlines the design and construction of a supersonic wind tunnel with diagnostic capabilities at Worcester Polytechnic Institute. The project involved three main components: 1) design and fabrication of the wind tunnel channel and flange, 2) creation of a Pitot-static probe measurement system and data acquisition, and 3) development of a schlieren flow visualization system. Previous work at WPI included initial designs of supersonic wind tunnels to interface with an existing vacuum chamber. The current project builds upon this work to add diagnostic systems and allow for future testing and research applications.
Experimental Investigation of Mist Film Cooling and Feasibility SReda Ragab
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Thesis Statement for students diagnonsed withADHD.ppt
Investigation Periodic Faults in Yarn
1. i
INVESTIGATIVE STUDY OF PERIODIC YARN FAULTS AND
ITS REMOVAL BY USING GEARING ANALYSIS
A Thesis Submitted To
Bahauddin Zakariya University College of
Textile Engineering, Multan
By
MUHAMMAD RIZWAN 11-TE-13
MUHAMMAD MUNAWAR 11-TE-29
MUHAMMAD ASAD 11-TE-30
YASIR AKHTAR 11-TE-40
BAHAUDDIN ZAKARIYA UNIVERSITY COLLEGE OF TEXTILE
ENGINEERING, MULTAN
December, 2015
2. ii
CANDIDAT’s DECLARATION
We certify that the thesis entitled” Investigative Study Of Periodic Yarn Faults And Its
Removal By Gearing Analysis” submitted for the degree of B.sc Textile Engineering is
the result of our own research, except where otherwise acknowledged, and that this thesis in
whole or in part has now been submitted for an award, including a higher degree, to any
other university or institution.
Muhammad Rizwan
Signed: ---------------------- Date: 14/12/2015
Muhammad Munawar
Signed: ---------------------- Date:14/12/2015
Muhammad Asad
Signed: ---------------------- Date:14/12/2015
Yasir Akhtar
Signed: ---------------------- Date:14/12/2015
3. iii
CERTIFICAT
It is to certify that this thesis entitled “Investigative Study of Periodic Yarn Faults
and Its Removal by Using Gearing Analysis” has been accepted as a partial
fulfillment of the requirement for the degree of B.sc Textile Engineering in
Bahauddin Zakariya University College of Textile Engineering Multan.
Associate Supervisor: -------------------- Principle Supervisor: ---------------------
Project Coordinator: --------------------- External Examiner: ----------------------
Vice Principal: ------------------------
5. v
ACKNOWLEGEMENT
First of all we want to thank AL-MIGHTY ALLAH who made us able to do this.
We are thankful to our parents who like to see us successful in all fields of life and
pray for us to have a happy and long live.
We would like to express my special thanks of gratitude to my teacher Mr.
Muhammad Furqan Khurshid as well as our vise principal Mr. Tahir Bappi and Mr.
Ahsanullah (General Manager of Unit No.4, Fazal Cloth Mills, Fazal Nagar Jhang
Road, Muzaffargarh) who gave us the golden opportunity to do this wonderful
project on the topic ,“Investigative Study Of Periodic Yarn Faults And Its Removal
By Using Uster Quantum” which also helped using doing a lot of Research and we
came to know about so many new things. We are really thankful to them.
We want to thank administration and staff of Unit No.4, Fazal Cloth Mills, Fazal
Nagar Jhang Road, Muzaffargarh who were very kind and supportive to us.
Especially to Mr. Ahsanullah(General Manager of Unit No.4, Fazal Cloth Mills,
Fazal Nagar Jhang Road, Muzaffargarh) who helped us throughout the project and
gave free hand to perform our experiment.
We are thank full to our beloved senior Laal Khan, great teacher and again project
supervisor Mr. Furqan Khurshid, the guidance of whom has been always source of
light in darkness and he was always available to us. In difficult process of compiling
and writing of our project we are very thankful to him who told us the right way of
doing this.
6. vi
ABSTRACT
It has been widely reported that periodic faults in cotton yarn are one of the main
reasons of yarn rejection from weaving mill. This thesis has been undertaken to
study periodic faults produced in cotton ring spinning mill, its rectification and
prevention from occurring. The purpose of periodic yarn fault detection system was
to identify defective part in the machine. This system is suitable for identifying the
source of periodic fault on the machine. It was developed because spectral analysis
of machines with complex driving systems requires time and work-consuming
calculations, which make it considerably more difficult to quickly find the cause of
the detected periodicity in the stream of fibers.
7. vii
TABLE OF CONTENTS
CHAPTER # 1 INTRODUCTION........................................................................1
1.1 Yarn ...............................................................................................................1
1.2 Types of Yarn.................................................................................................1
1.2.1 Filament Yarn ..........................................................................................1
1.2.2 Staple or Spun Yarn .................................................................................1
1.3 Manufacturing Process of Staple or Spun Yarn...............................................2
1.4 Brief Introduction of Departments ..................................................................3
1.4.1 Blow Room Process.................................................................................3
1.4.2 Carding Process .......................................................................................3
1.4.3 Combing process......................................................................................4
1.4.4 Drawing frame Process ............................................................................4
1.4.5 Roving frame ...........................................................................................5
1.4.6 Ring Spinning Process .............................................................................5
1.4.7 Cone Winding Process: ............................................................................7
1.5 Yarn Faults.....................................................................................................8
1.6 Yarn Faults Classification...............................................................................8
1.6.1 Classimat Faults.......................................................................................9
1.6.2 Deviation in Yarn Quality Faults..............................................................9
1.6.3 Periodic Yarn Faults...............................................................................16
CHAPTER #2 Materials and Method.................................................................26
2.1 Material........................................................................................................26
2.2 Method.........................................................................................................28
2.2.1 Identify the periodic fault length by mass spectrogram...........................28
2.2.2 Analysis the Gearing System..................................................................29
2.2.3 Identify Origination Point of Yarn Fault.................................................30
2.2.4 Rectification of Yarn Faults ...................................................................30
CHAPTER #3 RESULTS AND DISCUSSION ..................................................31
3.1 Investigation and rustication of periodic faults at breaker..............................31
3.1.1 Identify the periodic fault length by mass spectrogram...........................31
3.1.2 Analysis the gearing system ...................................................................32
3.1.3 Identify Origination Point of Yarn Fault.................................................33
3.1.4 Rectification of Yarn Faults ...................................................................34
8. viii
3.2 Investigation and rustication of periodic faults at Finisher.............................35
3.2.1 Identify the periodic fault length by mass spectrogram...........................35
3.2.2 Analysis the Gearing System..................................................................36
3.2.3 Identify origination point of yarn fault....................................................37
3.3 Investigation and rustication of periodic faults at Simplex ............................39
3.3.1 Identify the periodic fault length by mass spectrogram...........................39
3.3.2 Analysis the Gearing System..................................................................40
3.3.3 Identify origination point of yarn fault....................................................42
3.3.4 Rectification of Yarn Faults ...................................................................42
3.4 Investigation and rustication of periodic faults at Ring..................................43
3.4.1 Identify the periodic fault length by mass spectrogram...........................43
3.4.2 Analysis the Gearing System..................................................................44
3.4.3 Identify Origination Point of Yarn Fault.................................................45
3.4.4 Rectification of Yarn Faults ...................................................................46
Conclusions ..........................................................................................................47
References ............................................................................................................47
9. ix
LIST OF FIGURES
FIGURE 1.1: FLOW CHART OF SPUN YARN MANUFACTURING PROCESS......................2
FIGURE 1.2: CLASSIFICATION OF YARN.....................................................................8
FIGURE 1.3: CLASSIFICATION MATRIX IN CLASSIMAT................................................9
FIGURE 1.4: EFFECT OF COUNT VARIATION ON THE FABRIC SURFACE.....................10
FIGURE 1.5: HAIRINESS ON THE SURFACE OF YARN................................................14
FIGURE 1.6: DIFFERENCE IN PERIODICITY................................................................17
FIGURE 1.7: MOIRÉ EFFECT.....................................................................................18
FIGURE 1.8: AMPLITUDE OF PERIODIC FAULT..........................................................19
FIGURE 1.9: NORMAL MASS SPECTROGRAM ............................................................20
FIGURE 1.10: EXAMPLE OF SPECTROGRAM OF CHIMNEY FAULT..............................22
FIGURE 1.11: EFFECT OF CHIMNEY FAULT ON YARN ..............................................22
FIGURE 1.12: EXAMPLE OF SPECTROGRAM OF HILL TYPE PERIODIC FAULT.............23
FIGURE 1.13: SPECTROGRAM AND YARN BOARD IMAGE OF A BAD OE YARN..........25
FIGURE 2.1: SEQUENCE OF MACHINES FOR YARN PREPARATION .............................27
FIGURE 2.2: SPECTROGRAM REPRESENTING PERIODIC FAULT ..................................28
FIGURE 2.3: DRAFTING ELEMENTS OF A RING SPINNING MACHINE WITH GEARING
DRIVE .............................................................................................................29
FIGURE 3.1: GEARING DIAGRAM OF DRAWING BREAKER ........................................32
FIGURE 3.2: GEARING DIAGRAM OF DRAWING FINISHER .........................................36
FIGURE 3.3: GEARING DIAGRAM OF SIMPLEX FL-100..............................................40
FIGURE 3.4: GEARING DIAGRAM OF RING FRAME RX-240.......................................44
10. x
LIST OF TABLES
TABLE 2.1: THE PROPERTIES OF COTTON ...............................................................26
TABLE 2.2: PARAMETERS USED IN THE EXPERIMENTS .............................................27
TABLE 3.1: PERIODIC FAULT LENGTHS OF DIFFERENT PARTS OF BREAKER ..............33
TABLE 3.2: PERIODIC FAULT LENGTHS OF DIFFERENT PARTS OF FINISHER...............37
TABLE 3.3: PERIODIC FAULT LENGTHS OF DIFFERENT PARTS OF SIMPLEX FL-100....41
TABLE 3.4: PERIODIC FAULT LENGTHS OF DIFFERENT PARTS OF RING FRAME RX-240
.......................................................................................................................45
11. 1
Chapter: Introduction
-------------------------------------------------------------------------------------------------------------------------
1.1 Yarn
A yarn is defined as a product of substantial length and relatively small cross section
consisting of fiber and/or filament with or without twist.[1]
OR
A Yarn is long length continuous strand of twisted fibers of natural or synthetic
material, such as cotton, wool or nylon, used in weaving or knitting. [2]
The characteristics of spun yarn depend, in part, on the amount of twist given to the
fibers during spinning. A fairly high degree of twist produces strong yarn; a low
twist produces softer, more lustrous yarn; and a very tight twist produces crepe yarn.
Yarns are also classified by their number of parts. A single yarn is made from a
group of filament or staple fibers twisted together. Ply yarns are made by twisting
two or more single yarns. Cord yarns are made by twisting together two or more ply
yarns.
1.2 Types of Yarn
There are two classifications of yarns that will be produced by spinning which are
Filament and Staple yarns.[3]
1.2.1 Filament Yarn
These yarns are made from long, and continuous strands of fiber. Most of them from
synthetic and only silk represents for natural fibers in filament.
1.2.2 Staple or Spun Yarn
Staple or spun yarns in other hand are made from short length of fibers. It can be
found from natural fibers or can be produced using synthetic as staple filament
yarns. As it is short length, staple fibers need to be held together with others in order
to get the long and continuous yarns.
12. 2
1.3 Manufacturing Process of Staple or Spun Yarn
Staple yarn manufacturing is a sequence of processes that convert raw cotton fibres
into yarn suitable for use in various end-products. A number of processes are
required to obtain the clean, strong, uniform yarns required in modern textile
markets. Beginning with a dense package of tangled fibres (cotton bale) containing
varying amounts of non-lint materials and unusable fibre (foreign matter, plant trash,
motes and so on), continuous operations of opening, blending, mixing, cleaning,
carding, drawing, roving and spinning are performed to transform the cotton fibres
into yarn.[3]
Figure 1.1: Flow Chart of Spun Yarn Manufacturing Process
13. 3
1.4 Brief Introduction of Departments
1.4.1 Blow Room Process
Blow room is the initial stage in spinning process. The name blow room is given
because of the “air flow” And all process is done in blow room because of air flow.
Blow room is consisting of different machines to carry out the objectives of blow
room. In blow room the tuft size of cotton becomes smaller and smaller due to that
cleaning also done. Mixing of cotton is done separately as well as in blow room.
Compressed layer of bale is also open in blow room with the help of machine. Other
contamination in the cotton such as leaf, stone, iron particles, jute, poly
propylene, colored fibers, feather and other foreign material also remove from
cotton by opening and beating. Then open material feed to the next carding process
uniformly.[4]
1.4.2 Carding Process
Carding process is very important role in spinning mill. It helps us both way to open
the tuft into a single fiber and to remove the impurities and naps. Textile experts are
convinced for the accuracy of following statement.
“The card is the heart of spinning mill” and “well carded is well spun” (Vijykumar,
2007) [5]
Card feeding is done by two ways. One is manually and other is through chute feed
system. In manual case the lap which is produced in blow room and it is feed to the
card. In chute feed the material is feed through air flow system to card
machine. It is important to say that lower the feed variation better is the carding
quality. Lower the feed variation then draft variation will also be less. Then yarn
quality will be consistent. If the card is having auto leveler then nominal draft
should be selected properly. In some circumstances card also act as a cleaner
and remove a certain amount of short fiber. Approximately 90% cleaning
efficiency is achieved with the help of carding machine.[6]
14. 4
1.4.3 Combing process
For getting high quality of yarn, one extra process is introduced which is called
combing process.
Combing is an operation in which dirt and short fibers are removed from sliver lap
by following ways. In a specially designed jaws, a narrow lap of fiber is
firmly gripped across its width. Closely spaced needles are passed through the fiber
projecting from jaws. Short fiber which we remove is called comber noil. The
comber noil can be recycled in the production of carded yarn. Yarn which is
get from comber sliver is called comber yarn. Carded sliver are combine into
comber lap in a single continuous process stage. Flat sheet of fiber which is get from
comber lap is fed into the comber in an intermediate.
There are different ways by which value of combing is used in the manufacturing of
cotton. By spinning point of view combing process makes more uniformity in the
yarn. Strength of yarn is also high because in combing process short fiber are
removed and only fiber having good strength remains. So it play very
important role for increasing the yarn strength. Because of straightened
condition of fibers combing makes possible spinning smoother and more
lustrous yarn. In combing process length of fiber are strong so it need less
twist produced then carded yarn. [7]
1.4.4 Drawing frame Process
Draw frame is simple and cheap machine. In spinning regarding to quality point of
view it play very important role .If its setting is not done properly then it affects yarn
strength and elongation. For improving quality draw frame is final process in the
spinning mill. It effects on quality especially on evenness of sliver. In the spinning
process there are chances of elimination of errors in draw frame machine. Draw
frame play very important role for the quality of yarn. Without it participation
quality can never be improved.[8]Drafting arrangement is the heart of the draw
frame. Drafting arrangement should be simple, stable design, should have
ability to produce high quality product. It should have high fiber control.
15. 5
Auto leveler is also used to adjust and to improve the linear density of the
sliver. Without auto leveler it is very difficult to improve the quality of the draw
frame sliver.
1.4.5 Roving frame
It is an intermediate process in which fibers are converted into low twist lea called
roving. The sliver which is taken from draw frame is thicker so it is not suitable for
manufacturing of yarn. [7]
Its purpose is to prepare input package for next process. This package is to
prepare on a small compact package called bobbins. Roving machine is
complicated, liable to fault, causes defect adds to the production costs and
deliver the product. In this winding operation that makes us roving frame complex.
There are two main basic reasons for using roving frame. The roving sliver is thick
and untwisted. Because of it hairiness and fly is created. So draft is needed to
reduce the linear density of sliver. The ring drafting arrangement is not capable that
it may process the roving sliver to make the yarn.
Draw frame can represent the worst conceivable mode of transport and
presentation of feed material to the ring spinning frame.
1.4.6 Ring Spinning Process
Ring Spinning machine is used in textile industry to twist the staple fibers into a
yarn and wind on a bobbin for the winding section for more precise the yarn
to minimize the defects of end yarn. Ring machine is very important due to yarn
quality. Ring Spinning is the most costly step to convert fibers into yarn and
approximately 85% yarn produced in ring spinning frame all over the world. It is
made to draft the roving into a desired count and impart the desired twist to produce
the strength in the yarn. If twist is increased, yarn strength is also increased at
optimum limit.[2]
The input of ring frame is roving which comes from roving section this is final stage
where yarn is make. Here in this section need more drafting to reduce the liner
density of roving and more twist to make a yarn. The output of ring frame is yarn
which is wound on a ring bobbin which is used for next winding process.
16. 6
1.4.6.1 Function of Ring Process
There is a different function of Ring Spinning process in which roving is
converted into yarn through passing different zone like drafting, twisting and
winding zone. There are three important zone of Ring processes below here. [9]
Drafting Zone
Twisting Zone
Winding Zone
1.4.6.1.1 Drafting Zone
Drafting is the first zone of ring process and is very important part of machine and
mostly effects on the evenness and strength of yarn. In quality point of view, there
are many points which are related to the quality of drafting system.
Type of the draft
Selection of drafting parts like apron, rubber cots and spacer.
Range of draft
Draft designing and setting
Service and maintenance
Type of perforated drum
1.4.6.1.2 Twisting Zone
It is the second zone and is also very important part of Ring machine in which
the strands of fiber are converted into a yarn by the twist inserted. The strength of
yarn is depend upon the amount of twist which are given in twisting zone and it is
most important than other zone due to required strength of yarn. There are some
very important points related to quality point of view in twisting zone are;
Material and type of traveler
Wear resistance
Lubrication of fiber
Smooth running
Spindle and Traveler Speed
17. 7
1.4.6.1.3 Winding Zone
This is the last section of ring machine in which yarn is wound on the plastic bobbin
by the up and down movement of ring rail which is linked to a small motor. It is also
very important because the setting of ring rail makes coils of yarn on bobbin in such
a way that the Z-twist is not open during winding process. Some points are very
important during winding process. That’s are;
Ring rail speed setting
Bobbin material
No. of coils per inch
1.4.6.2 Ring Spinning Effects on Quality
Ring spinning is the first stage of post spinning in which yarn produced from
the roving installed on the hanger on the ring machine. Ring process is the heart of
textile plant and there is lot of factors effect on the yarn quality. Speed of machine
makes a major role on the yarn quality, as the speed increase of ring
machine, the imperfection (Neps 200%, Thick +50, Thin -50) of yarn increase.
Hairiness is also affected in ring production process and mainly produced by
the movement of burnt traveler and high speed of machine.CV of count is also very
important and ring spinning process is the last stage of process where we can reduce
the CV of yarn count. Imperfection of yarn count in quality point of view is so
important that every customer required this quality standard, that imperfection
should be minimum as possible. [9]
1.4.7 Cone Winding Process:
It is the last section of yarn manufacturing process where auto cone machines are
installed and take an input material from ring spinning section as a yarn bobbin and
give a yarn on paper cone after passing detecting instrument as an output. In
winding section, there are lot of heads in auto cone machines use to wound the yarn
from ring bobbin yarn to paper cone yarn. Now days, there are some companies to
manufacturing these machines and Savio company is one of them which produce a
fully automatic machine for spinning industries. In quality point of view, it is a very
good machine and has also very low maintenance cost.
18. 8
Winding department plays an important role in the production and quality of
yarn and causes direct effect on them. The yarn which made in ring section is not
finish yarn and can’t sell to customer. After making the yarn in ring process,
auto cone section made it more even yarn by passing through the optical
sensor and capacitor sensor which is installed in different heads of machine.
The yarn which is obtained from winding section is able to sell the customers.
1.5 Yarn Faults
Yarn faults may be defined as yarn irregularities that can lead to difficulties in
subsequent production stages, or to defects in fabric.
1.6 Yarn Faults Classification
Figure 1.2: Classification of Yarn
YARNFAULTS
CLASSIMATE
SELDOM
OCCURING
RANDOM
OCCURING
Physical
COUNT CV
U %
HARINESS
CONTAMINATION
IPI
STRENGTH
PERIODIC
PERIODIC
NON PERIODIC
19. 9
1.6.1 Classimate Faults
The position of the frequent yarn faults (imperfections) in comparison to the position of
the seldom-occurring yarn faults in the classification matrix are shown in the figure. It
becomes clear, that both types of yarn faults differ from each other clearly by their size
and thus, cannot be compared with each other. In addition, the areas of the clearer
settings N, S, L, T, CCp and CCm are indicated in Fig. This shows where the settings are
effective. [16]
Figure 1.3: Classification matrix in Classimat
1.6.2 Deviation in Yarn Quality Faults
COUNT CV
IRREGULARITY
HARINESS
IMPERFECTIONS
STRENGTH
1.6.2.1 Count Variation
This is usually expressed in terms of CV between hank length such as 100 or 50
meter. In case of drawn and spun yarns, long term irregularity arises from variation
either between groups, between bobbins or within bobbins. Between groups
variation represents the difference between spinning frames, frame sides and times
of spinning, whereas between[11][12]
20. 10
Figure 1.4: Effect Of Count Variation On The Fabric Surface
(Combed cotton 100%, Nec 30, Nm 50, 20 Tex)
1.6.2.1.1 Within Bobbins Count Variation
High card sliver & comber sliver U%
High tension draft or improper coils in bobbins variations
Irregular drafting &n stretching on speed frame.
Retching in roving
Use of separator plates at high spindle speeds.
Excessive pinion changes in ring spinning
Defective draw frame is a single major cause for with in bobbins variation,
such as excessive creel or web tension, roller slippage in drawing and
adverse humidity conditions in hair the draw frame drafting leading to within
bobbins variations.
Low humidity
1.6.2.1.2 Between Bobbin Count Variation
Variation in average lap weight over long intervals (e.g. half shift) including
allowance to variation in humidity
High cm to cm variation in lap
21. 11
Excessive variation in tuft size
Draft to waste difference between groups of cads or at combers.
Hank differences between D.F slivers
Stretch in the D.F slivers fed to roving
Use of one passage post comber D.F
Row to row differences in hank roving.
Draft differences between roving frame
Marked changes in hank roving over a roving frame bobbins caused by
irregular bobbins speed control
Draft differences between ring frame
Frequent changes of pinion in drawing and ring spinning
Creel draft variation and bobbin holders clogging with waste
Variation in top roller pressure
Variation in bare bobbins diameter
Spindle variation in ring finish
High variation in RH% age
At several stages in spinning process stretch take place and become a source of great
hidden menace as it not only undesirable variation (between bobbins and within
bobbins) but also results in high end breakages excessive wastes and lower the
quality of end product.
1.6.2.2 Yarn Irregularity
All spun yarns are to some extent irregular it is the degree of irregularity which
determines whether it is acceptable or not for a particular end use. Appearance of
many fabrics is influenced by yarn irregularity hence this is frequently regarded as
one the most important yarn characteristics. Yarn irregularity is usually taken to
means the variations of mass per unit length variations in twist and strength and the
diameters are to large extent secondary or tertiary effects of variations in mass per
unit length. Gross variation (yarn faults) are the abnormal variations in the yarn
thickness, Yarns produced from very short fibers may contain short variation in
thickness. Fibers with the greater variation of their diameter have more irregular
yarn.
22. 12
Yarn unevenness is much affected by roving and draft conditions. Long irregularity
is related to fore spinning process of middle roller of ring frame while short term
irregularity mainly process after middle roller of ring frame. Main factors involved
in the formation of short term irregularity are: limited irregularity due to random
fiber arrangement, imperfect fiber control which in roller drafting leads to drafting
waves varying in amplitude and length; and mechanical defects. The pattern of
irregularity in drawn and spun yarn is complex combination of wave length
introduced at each stage of drawing and in spinning. The most important wave is the
one with the shortest wavelength-introduced at the spinning frame. Long term count
variation may be influenced by the no. of doublings used during drawing and
spinning, short term irregularity is hardly influenced by this factor.[13]
There reasons are given below
Faulty roving
Faulty rotation of skewers
Wrong guiding of roving in creel
Chocking of trumpet
Faulty working of traverse bar
Wrong roller setting
Inadequate pressure on top roller
Eccentricity of rollers
Roller lapping & sticking
Defective & worn gears & bearings
Uneven dia. of rubber cots
Non alignment of apron
Worn & damaged aprons
Accumulation of lint under apron
Incorrect gap between aprons
Wider gauge in front drafting zone
Incorrect setting of lappet & spindle
Rough surface of separators
Defective spindles
23. 13
Damaged & worn rings
Light travelers
Close setting of traveler cleaner
Erratic ring rail traverse
The mathematical statistics offer 2 methods to represent yarn irregularity as
following;
1.6.2.2.1 Mean Variation U%
It is the percentage mass deviation of unit length of material and is caused by
uneven fiber distribution along the length of the strand. U% is mostly measure in cut
length of 1 cm that indicated as Um (this is the U value you would have got from
cutting the yarn into approximately 1 cm sections and weighing those short
sections.).The irregularity U% is proportional to the intensity of the mass variations
around the mean value. The U% is independent of the evaluating time or tested
material length with homogeneously distributed mass variation.
1.6.2.2.2 Coefficient Of Variation C.V. %
The standard deviation of the linear densities over which unevenness is measured
expressed as a percentage of the average linear density for the total length within
which unevenness is measured. C.V of irregularity can be measure using following
parameters;[14][15]
CVm: Coefficient of variation of mass with a cut length of approximately 1 cm. This
is the CV most often quoted in yarn specification and commercial transactions.
CVm (1m): Coefficient of variation of mass with a cut length of 1 m, simulating the
CV you would have got from cutting the yarn into 1 m sections and weighing those
sections. The same applies to CVm (10m) and CVm (100m). It should be noted that
as the cut length increases, the irregularity reduces.
1.6.2.3 Yarn Hairiness
Is a measure of the amount of fibers protruding from the structure of the yarn? Yarn
hairiness has many different effects on subsequent processing steps and on the
appearance of woven and knitted fabrics. . [15]
24. 14
During the weaving process, high hairiness can lead to entanglements of
warp threads.
Hairiness is high for low twist and vice versa.
Yarn winding will increase the yarn hairiness whereby the increase will
depend on the raw material, on the yarn twist and on the winding speed.
In uni-colored fabric, hairiness variations exceeding 1.5 between yarns lying
next to each other can be detected by the human eye.
The higher the hairiness, the softer a fabric.
Figure 1.5: Hairiness on the surface of yarn
1.6.2.4 Imperfections (Thin places, Thick places and Neps)
Thin places, thick places and neps are part of yarn unevenness. Deviations of the
mass from the average yarn body exceeding ±50% are counted as thin and thick
places. Neps are short thick places resulting from fiber entanglements of frequently
immature fibers or seed coat fragments. Imperfections in the cross-section of yarn
will heavily increase with higher yarn count, i.e. with fewer fibers in the cross-
section.
The higher the short fiber content, the higher the number of imperfections. Frequent
imperfections can be very disturbing in a fabric. Fiber entanglement often results
from immature fibers which cannot absorb dyestuff and, therefore, remain white.
25. 15
1.6.2.4.1 Thin place (-50%)
Number of places that have mass reductions of 50% or more with respect to the
mean value. Note that (-50%) is the standard sensitivity level used in the test. If a
different sensitivity level (-40%, -40%, -60%) is used, the result would have been
different. These thin places have a length of approx. 40 cm.
1.6.2.4.2 Thick place (+50%)
These are number of places that have mass increases of 50% or more with respect to
the mean value. Note that (+50%) is the standard sensitivity level used in the test. If
a different sensitivity level (+35%, +70%, +100%) is used, the result would have
been different. These thick places have a length of approx. 40 cm.
1.6.2.4.3 Neps (+200%)
Number of places that have mass increases of +200% or more with respect to the
mean value and a reference length of 1mm. Note that +200% is the sensitivity level
normally used in the test. These short thick places in a yarn are often the results of
vegetable matter or entangled fibers.
1.6.2.5 Strength
Yarn strength is measure in tensile strength, which is defined as:-
The variation of maximum tensile strength is a measure for strength variations from
bobbin to bobbin. The causes of lack in fiber strength are
Fiber strength
Fiber growth
Fiber damaging in the spinning process( inadequate roller gauge)
Excessive rubber cots hardness
Excessive top roller pressure
Loose spindle tape
RH%
Singles (when using double roving)
26. 16
Stretched roving due to improper regulation of bobbin speed on roving frame
and
poor handling of roving bobbins during transportation
Excessive twist
Defective piecing
Excessive short fibers content
Use of soft waste on mixing
Roving
1.6.3 Periodic Yarn Faults
The variation in mass per unit length of yarn comprises three basic types, namely (i)
irregularity of a completely random nature, (ii) irregularity of a markedly periodic
nature, (iii) irregularity of a quasi-periodic nature. Purely random irregularity forms
an unavoidable component of total irregularity, so that a minimum achievable
random irregularity can be acceptable for apparel usage. Periodic yarn faults are
thick and thin places, which always occur with the same distance from each other.
Such faults are caused in the spinning process, when yarn guiding elements are
defective. The periodic irregularities which are found in the spun yarns may be the
result of machinery defects such as eccentric drafting rollers, variability in the
covering of drafting rollers, inaccurately cut or worn-out drafting rollers and the
vibration of drafting rollers. Yarns which are affected by any of these defects
occurring in the drafting prior to spinning can appreciably affect the yarn and the
resulting fabric. An eccentric front roller of the ring spinning machine leads to a
periodic fault with a wavelength of 8 cm, as this roller always causes faulty drafts in
the draw-box within the same time intervals. The size of each individual fault is
mostly not disturbing. But as a series of yarn faults, they can very well be disturbing.
In most cases, disturbing periodic faults are formed at the ring-spinning machine.
Widely known are defects caused by cuts and pressure marks on the take-off
cylinder. By this, the continuous distribution of the fibers is disturbed, which results
in thin- and thick places. The size of the fault corresponds to an alteration/shift of all
fibers of about 30-50%. The fault length depends on the dimension of the defective
machine part. The distance between the single events corresponds to the
circumference of the roller, e.g. at the front roller of a draw-box. A further reason for
27. 17
periodic faults can be pressure marks on the top roller. If a spinning position or the
whole spinning frame is stopped and the pressure is not taken from the top roller, it
can lead to pressure marks on the top rollers after longer stops and thus to periodic
defects in the yarn.
Figure 1.6: Difference in periodicity
The distance between the single events corresponds to the circumference of the
cylinders. With soft, even lapping can lead to moiré pattern. Furthermore can a
missing bottom belt rubber coating of the top roller also lead to periodic faults.
There are many possibilities for the origin of periodic defects when spinning
compact yarns. The reasons depend strongly on the spinning method. For regular
ring spun yarns, the reasons are mostly pure mechanical insufficiencies, which lead
to periodic faults in the yarn. For compact yarns, the reasons can be found in the
contamination with fibers and dirt. This dirt can build up for an uncertain time,
which makes it much more difficult to find the reasons. Therefore, the monitoring of
periodic defects in compact yarns is essential.
28. 18
Figure 1.7: Moiré Effect
Mass variation in yarn can adversely affect many properties of textile materials such
as shade variations and strength. Mass variation can be attributed to the properties of
raw materials, inherent short comings in yarn making and preparatory machines,
mechanically defective machinery and/or external causes as a result of working
conditions and improper housekeeping.
Periodic mass variations in yarn can cause weft bars, diamond barring effects, moiré
effects, and weft stripes or rings in the resulting fabric. Hence, periodic irregularity
should not be permitted at all, since it greatly affects the appearance of fabric and
must be controlled. However, the presently available tools used to measure the
periodicity of mass per unit length variation have limitations. The spectrogram is
more reliable compared to other tools for determining periodicity; it works on the
principle of Fourier analysis, which sets out any function in a series of sine curves.
The actual mass variation will be resolved into different sinusoidal waves with
different amplitudes and wavelengths. Hence, spectrogram gives only the resolved
mass variation, which may not be present in the final yarn when different faults are
superimposed.
The spectrogram measures the periodic mass variations in a yarn by analyzing the
frequencies at which faults occur electronically. From the speed at which the yarn is
running the frequencies are converted to wavelengths and slotted into a finite
number of discrete wavelength steps. The result is a histogram as shown in Fig
29. 19
where the amplitude is a measure of the number of times a fault of that repeat length
occurs owing to the fiber length having an effect on the distribution of repeats
around that Length the background level of the spectrogram is not flat but a
periodically repeating fault will show a level much greater than the background as is
shown in the figure. As a general rule the height of a peak in the spectrogram should
not be more than 50% of the basic spectrogram height at that wave length.[10]
Figure 1.8: Amplitude of Periodic Fault
The wavelength of the fault gives an indication of its cause and therefore allows it to
be traced to such mechanical problems as drafting waves, eccentric or oval rollers in
the spinning plant or in earlier preparation stages. The wavelength can also
correspond to the diameter of the yarn package, in which case it will vary between
the full and empty package. The wavelength of a fault that occurs before the drafting
in the spinning process will be multiplied by the drafting ratio.
"DIAGRAM" is a representation of the mass variations in the time domain.
Whereas, spectrogram is a representation of the mass variation in the frequency
domain. Spectrogram helps to recognize and analyze the periodic fault in the sliver,
roving and yarn.
30. 20
Figure 1.9: Normal Mass Spectrogram
For textile application, the frequency spectrum is not practical. A representation
which makes reference to the wavelength is preferred. Wavelength indicates directly
at which distance the periodic faults repeat. The more correct indication of the curve
produced by the spectrograph is the wave-length spectrum. Frequency and
wavelength are related as follows frequency = (wavelength)/(material speed)
In the spectrogram, the X-axis represents the wavelength. In order to cover a
maximum range of wavelengths, a logarithmic scale is used for the wavelength
representation. The y-axis is without scale but represents the amplitude of the faults
in yarn.
The spectrogram consists of shaded and non-shaded areas. If a periodic fault passes
through the measuring head for a minimum of 25 times, then it is considered as
significant and it is shown in the shaded area. Wavelength ranges which are not
statistically significant are not shaded. In this range the faults are displayed but not
hatched. This happens when a fault repeats for about 6 to 25 times within the tests
length of the material. As far as those faults in the un-shaded area is concerned, it is
recommended to first confirm the seriousness of the fault before proceeding with the
corrective action. This can be done by testing a longer length of yarn. Faults which
occur less than 6 times will not appear in the spectrogram. A spectrogram starts at
1.1 cm if the testing speed is 25 to 200 m/min. It starts at 2.0cm if the testing speed
is 400 m/min and it starts at 4 cm if the speed is 800m.min. For spun material the
maximum wavelength range is 1.28 km. Maximum number of channels is 80.
Depending upon the wavelength of the periodic fault, the mass variations are
classified as
Short-Term Variation (wavelength ranges from 1 cm to 50cm)
31. 21
Medium-Term Variation (wavelength ranges from 50cm to 5 m)
Long-Term Variation (wavelength longer than 5 m)
Periodic variations in the range of 1 cm to 50 cm are normally repeated a number of
times within the woven or knitted fabric width, which results in the fact periodic
thick places or thin places, will lie near to each other. This produces, in most cases, a
"MOIRE EFFECT". This effect is particularly intensive for the naked eyes if the
finished product is observed at a distance of approx. 50 cm to 1m.
Periodic mass variations in the range of 50cm to 5m are not recognizable in every
case. Faults in this range are particularly effective if the single or double weave
width or the length of the stretched out yarn one circumference of the knitted fabric,
is an integral number of wave-lengths of the periodic fault, or is near to an integral
number of wave-lengths. In such cases, it is to be expected that weft stripes will
appear in the woven fabric or rings in the Knitted fabric.
Periodic mass variations with wave-lengths longer than 5m can result in quite
distinct cross-stripes in woven and knitted fabrics, because the wave-length of the
periodic fault will be longer than the width of the woven fabric or the circumference
of the knitted fabric. The longer the wavelength, the wider will be the width of the
cross-stripes. Such faults are quite easily recognizable in the finished product,
particularly when this is observed from distances further away than 1 m.
A periodic mass variation in a fiber assembly does not always result in a statistically
significant difference in the U/V value. Nevertheless, such a fault will result in a
woven or knitted fabric and deteriorate the quality of the fabric. Such patterning in
the finished product can become intensified after dyeing. This is particularly the
case with uni-colored products and products consisting of synthetic fiber filament
yarns. The degree to which a periodic fault can affect the finished product is not
only dependent on its intensity but also on the width and type of the woven or
knitted fabric, on the fiber material, on the yarn count, on the dye up-take of the
fiber, etc. A considerable number of trials have shown that the height of the peak
above the basic spectrum should not overstep 50% of the basic spectrum height at
the wavelength position where the peak is available.
32. 22
1.6.3.1 Chimney Type Faults:
The eccentricity roller results in a sinusoidal mass variation whereby the periodicity
corresponds to full circumference of the roller. With one complete revolution of an
OVAL roller, a sinusoidal mass variation also results, but 2 periodic faults are
available. Chimney type of faults are mainly due to -mechanical faults -eccentric
rollers, gears etc -improper meshing of gears -missing gear teeth -missing teeth in
the timing belts -damaged bearings etc
Example of a chimney:
Figure 1.10: Example Of Spectrogram Of Chimney Fault
Figure 1.11: Effect of Chimney Fault On Yarn
1.6.3.2 Hill Type Faults:
These faults are due to drafting waves caused by -improper draft zone settings -
improper top roller pressure -too many short fibers in the material, etc numerous
measurements of staple-fiber materials have shown that there are rules for the
correlation between the appearance of drafting waves in the spectrogram and the
mean staple length. It is given below
Yarn: 2.75 x fiber length
Roving: 3.5 x fiber length
33. 23
Combed Sliver: 4.0 x fiber length
Draw Frame Sliver: 4.0 x fiber length
A periodic fault which occurs at some stage or another in the spinning process is
lengthened by subsequent drafting. If the front roller of the second draw-frame is
eccentric, then by knowing the various drafts in the further processes, the position of
the peak in the spectrogram of the yarn measurement can be calculated. The
wavelength of a defective part is calculated by multiplying the circumference of the
part and the draft up-to that part. The wavelength of a defective part can be
calculated if the rotational speed of the defective part and the production speed are
known. Doubling is no suitable means of eliminating periodic faults. Elimination is
only possible in exceptional cases. In most cases, doubling can, under the best
conditions, only reduce the periodic faults. The influence of periodic mass variation
is proportional to the draft. Due to the quadratic addition of the partial irregularities,
the overall irregularity of staple-fiber yarns increases due to the periodic faults only
to an unimportant amount.
1.6.3.2.1 Drafting Faults
Another type of irregularity which is clearly visible in spectrograms is a drafting
fault. It is an exaggerated crest (hill) which results from poor fiber control in a
drafting zone.
Figure 1.12: Example of Spectrogram of hill type periodic Fault
Drafting faults are created and influenced by non-optimal settings of one or several
of the following factors:
- Gauge distance between the drafting rollers (Nip)
- Roller Pressure
34. 24
- State of the roller’s surfaces
- Humidity of material and surrounding climate
When searching to eliminate drafting faults, one would look for the main cause in
one of those factors first. In many cases though, a compromise has to be found, since
certain materials are more critical. Example: Combed cotton draw frame slivers,
where the fibers are highly parallel and thus slippery and difficult to draft optimally
at a reasonable speed. A drafting fault hill is to be found at a wavelength of about
2.8 × average fiber length. If the drafting fault hill does not lie around 2.8 × average
fiber length, one has to divide the wavelength λ of the hill crest by 2.8 × average
fiber length in order to get the approximate draft factor back to the origin of the
fault.
Formula:
1.6.3.3 Multiple Periods
In very many cases, a single periodic material fault produces multiple chimneys.
Multiple chimneys are the result of a periodic yarn mass variation which is not
evenly shaped, i.e. not sine-shaped. A multiple periodic fault consists of a base
wavelength and of so-called harmonic wavelengths. The harmonics are usually to
be found at factor 1/2, 1/3, 1/4, etc. of the base wavelength.
Example:
lengthfiberaverage
ratioDraft
cresthill
8.2
35. 25
Figure 1.13: Spectrogram and Yarn Board Image of a Bad OE Yarn.
The 10cm moiré was caused by a dirty Rotor groove.
The reason for the appearance of multiple chimneys lies in the behavior of wave signals.
Mathematically, it is complex (Fourier transformation), but graphically, it becomes quite
evident:
36. 26
Chapter: Materials and Method
-------------------------------------------------------------------------------------------------------------------------
2.1 Material
Four outputs from Breaker, Finisher, Roving and Ring were chosen as raw material
for investigation of periodic yarn faults. These products were processed on the
standard spinning machinery with Pakistani Cotton. The properties of this cotton are
given in the table.
Table 2.1: The Properties Of Cotton
Parameter Mean
Cotton Type Carded Combed
SCI 126.69 132.75
Mic 4.35 4.64
Mat 0.88 0.9
Length (Inch) 1.078 1.106
Unf. 82.66 83.5
SFI (%) 7.61 7.14
Str. (g/tex) 29.81 31.01
Trash 7.77 6.91
Moist. (%) 8.84 9.12
Rd. 72.61 73.52
+b 8.66 8.23
All samples from breaker sliver, finisher sliver, simplex roving and ring yarn were
prepared in “Fazal Cloth Mills, Unit # 4” by using Automatic Bale Opener Blow room
setup of Trutzschler Company, Trutzschler TC-03 card, Draw frame breaker Reiter
Rsb-2, Finisher Reiter RSB-D 40, speed frame Fl-100 and ring frame RX-240. The
sequence of machines is shown in the figure 2.1. Parameter, that were used for the
preparation of breaker sliver, finisher sliver, simplex roving and ring yarn on each
machine are in the Table 2.2.
The linear densities of the prepared breaker sliver, finished sliver, and roving were
68 grains/yard, 65 grains/yard, and 0.74 hanks respectively. Yarn samples of and
37. 27
21/1 Nec were prepared from rovings at a spindle speed of 21500 rpm with a twist
multiplier of 3.75 respectively.
Figure 2.1: Sequence of Machines for Yarn Preparation
Table 2.2: Parameters Used In the Experiments
38. 28
2.2 Method
Before testing, all the prepared yarn samples were conditioned in the laboratory
under standard atmospheric conditions of 21±1°C and a relative humidity of 65±2.
The periodic faults at breaker sliver, finisher sliver, simplex roving and ring yarn
were investigated and analyzed and rectified by following steps.
1. Identify the periodic fault length by mass spectrogram.
2. Analysis the gearing system
3. Identify origination point of yarn fault
4. Rectification of yarn faults
2.2.1 Identify the Periodic Fault Length By Mass Spectrogram
When sliver, roving or yarn is tested by UT-4, it provides us mass spectrogram of
material. In the spectrogram, the X-axis represents the wavelength. In order to cover
a maximum range of wavelengths, a logarithmic scale is used for the wavelength
representation. The y-axis is without scale but represents the amplitude of the faults
in yarn.
Figure 2.2: Spectrogram Representing Periodic Fault
The spectrogram consists of shaded and non-shaded areas. If a periodic fault passes
through the measuring head for a minimum of 25 times, then it is considered as
significant and it is shown in the shaded area. Wavelength ranges which are not
statistically significant are not shaded. In this range the faults are displayed but not
hatched. This happens when a fault repeats for about 6 to 25 times within the tests
39. 29
length of the material. As far as those faults in the un-shaded area is concerned, it is
recommended to first confirm the seriousness of the fault before proceeding with the
corrective action. This can be done by testing a longer length of yarn. Faults which
occur less than 6 times will not appear in the spectrogram.
2.2.2 Analysis the Gearing System
Gearing diagrams and their relative wavelengths are analyzed by using following
principle. Suppose a machine have following diagram.
Figure 2.3: Drafting Elements of a Ring Spinning Machine with Gearing Drive
Periodicity of front roller (λ 1) = λ 1 = DFR x π = 2.54 x π ≈ 8 cm
Periodicity of Z2 Gear = λ2 = λ1 x = 8 x = 88 cm
If the gear Z3 is defective, then the effect in the fiber material is the same as that
produced with the gear Z2, because both gears are on the same shaft.
Periodicity of Z4 Gear = λ3 = λ1 x x = 8 x x = 8.33 = 264 cm
= 2.64 m
The front roller, therefore, turns 33 times until the defect at Z4is repeated. A defect
of the gear Z4 directly affects the back roller BR because this gear is on the same
shaft. The influence on the back roller, multiplied by the total draft, results in the
40. 30
same wave-length as the influence of Z4on the front roller: Circumference of the
back roller
UBR = DBR x π = 2.54 x π ≈ 8 cm
Wave-length at the output of the draw-box: λ 4 = UBR x Vtot = 8.33 = 264 cm
= 2.64 m
Here, Vtot = total draft
A defect of the gear Z4 affects the middle roller MR in the following manner
(Z4 and Z5 are on the same shaft):
λ`5 = UMR x x = 2.3 x π x x = 8.89 cm
Wave-length at the output of the draw-box: λ5 = D2 x λ`5 = 29.6 x 8.89 ≈ 263cm
= 2.63 m
So, using above principle, we analyze the gearing systems of Breaker, Finisher,
Simplex and Ring. The gearing diagrams along with wave length of each part are
given below.
2.2.3 Identify Origination Point of Yarn Fault
When searching the origin of the periodicity, the first step is to remember that the
fault is caused by a moving machine part, usually a rotating one. It can be directly
touching the material (rollers, coiling, etc.) or in the machine drive (gears, pulleys,
etc.). By using above analysis, location of periodic fault is identified by comparing
the wave calculating from the gearing system with mass spectrogram.
2.2.4 Rectification of Yarn Faults
Once the yarn fault and defective part is localized, then that defective part is
replaced by taking suitable measures or it is eliminating from the yarn by using
classimate setting termed as PC.
41. 31
Chapter: Results and Discussion
-------------------------------------------------------------------------------------------------------------------------
3.1 Investigation and Rectification of Periodic Faults at Breaker
3.1.1 Identify the Periodic Fault Length By Mass Spectrogram
43. 33
Table 3.1: Periodic Fault lengths of Different Parts of Breaker
3.1.3 Identify Origination Point of Yarn Fault
As you can see from the spectrogram chart peak of unacceptable length is shown in red
color approximately at 61~62cm, which cause periodic variation in yarn and can create
difficulties in subsequent processes. On the basis of analysis of the gearing system, λd2 is
the faulty middle roller which produces this peak.
44. 34
3.1.4 Rectification of Yarn Faults
When medium roller was checked, there was a cut in the top medium roller. So,
medium roller was changed and hence fault was removed. And UT4 report after
removal of fault is given below.
Hence it proves that our periodic fault detection system was working properly.
45. 35
3.2 Investigation and Rectification of Periodic Faults at Finisher
3.2.1 Identify the periodic fault length by mass spectrogram
46. 36
3.2.2 Analysis the Gearing System
Figure 3.2: Gearing Diagram of Drawing Finisher
47. 37
Table 3.2: Periodic Fault lengths of Different Parts of Finisher
3.2.3 Identify Origination Point Of Yarn Fault
From this fig it is seen clear that peak is higher than acceptable limits so by
matching the values of spectrogram with PERIODIC FAULT DETECTION
SYSTEM. We can compare the value of λ. By comparing it is noted that this peak is
equal to λ NW1 (58.206 cm). Peak which shows that λNW1 gear is faulty.
3.2.4 Rectification of Yarn Faults
When gearing system was checked, there was a problem in λNW1. So, λ NW1 was
changed and hence fault was removed. And UT4 report after removal of fault is
given below.
52. 42
3.3.3 Identify Origination Point of Yarn Fault
From this fig it is seen clear that peak is higher than acceptable limits so by
matching the values of spectrogram with PERIODIC FAULT DETECTION
SYSTEM. We can compare the value of λ. By comparing it is noted that this peak is
equal to λ d(36 tooth gear of Simplex). Peak which shows that λd gear is faulty.
3.3.4 Rectification of Yarn Faults
When roller in the gearing named as d roller was checked, there was a damaged
tooth in that roller. So, roller was changed and hence fault was removed. And UT4
report after removal of fault is given below.
53. 43
3.4 Investigation and Rectification of Periodic Faults at Ring
3.4.1 Identify the Periodic Fault Length by Mass Spectrogram
54. 44
3.4.2 Analysis the Gearing System
Figure 3.4: Gearing Diagram of Ring Frame RX-240
55. 45
Table 3.4: Periodic Fault lengths of Different Parts of Ring Frame RX-240
3.4.3 Identify Origination Point Of Yarn Fault
From this fig it is seen clear that peak is higher than acceptable limits so by
matching the values of spectrogram with PERIODIC FAULT DETECTION
SYSTEM. We can compare the value of λ. By comparing it is noted that this peak is
equal to λFR (Front Roll in the Ring). Peak which shows that λFR gear is faulty.
56. 46
3.4.4 Rectification of Yarn Faults
When front roller was checked, there was a cut in the top front roller. So, front roller
was changed and hence fault was removed. And UT4 report after removal of fault is
given below.
57. 47
Conclusions
In this work, periodic yarn fault detection system was developed. It is suitable for
identifying the source of periodic fault on the machine. It was developed because
spectral analysis of machines with complex driving systems requires time and work-
consuming calculations, which make it considerably more difficult to quickly find
the cause of the detected periodicity in the stream of fibers. The result shows that
this system is helpful to eliminate periodic yarn faults of breaker, finisher simplex
and ring machines.
58. 48
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