The draw frame is a crucial machine in the textile manufacturing process, primarily used in the spinning sector to improve the quality of sliver by doubling, drafting, and aligning the fibers to ensure uniformity and consistency before the roving and spinning stages. It plays a significant role in enhancing the evenness, strength, and parallelization of fibers, ultimately affecting the quality of the final yarn. The draw frame typically operates by taking multiple slivers from the carding or combing process and passing them through a series of drafting rollers, which reduce the thickness of the sliver while increasing its length. This process is essential to reduce fiber irregularities and improve the uniformity of the mass distribution, which helps prevent weak spots and defects in the yarn. The drafting mechanism, consisting of multiple roller pairs with different speeds, stretches the fiber bundle to achieve the desired fineness. Modern draw frames are equipped with auto-leveling devices that continuously monitor and correct the sliver’s linear density, ensuring that variations in weight per unit length are minimized, thus maintaining consistency. Additionally, the slivers are passed through coilers, which neatly deposit the processed sliver into cans for further processing. The key functions of a draw frame include straightening the fibers, removing short fibers, improving blending efficiency, and enhancing fiber cohesion, all of which are critical in producing high-quality yarns with superior tensile strength, reduced hairiness, and better evenness. Various factors affect the efficiency and performance of the draw frame, including roller settings, drafting zone temperature and humidity, fiber type, and machine speed. Proper maintenance, including regular cleaning of drafting rollers and aprons, lubrication of moving parts, and checking of sensors and auto-leveling devices, is essential to ensure smooth operation. The introduction of computerized and high-speed draw frames has significantly improved productivity and efficiency in modern textile mills, allowing for real-time monitoring of sliver quality, fault detection, and reduced waste generation. Furthermore, advanced draw frames now integrate optical and capacitive sensors to detect and correct irregularities, ensuring higher accuracy and quality consistency in sliver formation. In cotton spinning, the draw frame is often positioned after the carding machine, while in worsted spinning systems, it follows the combing process to further refine the fiber arrangement. The doubling process in draw frames, where multiple slivers are combined and drafted, helps in averaging out inconsistencies from the previous processes, thus reducing mass variations. The ratio of input to output slivers, known as the doubling factor, varies based on the fiber type and yarn specifications, typically ranging from four to eight.

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Draw Frame in
Textile
Manufacturing
By Sayan Kundu

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Introduction
The draw frame is a process that is vital for yarn spinning, enhancing
sliver quality and uniformity. It prepares sliver for processes like
spinning, impacting yarn quality significantly.
The global textile market is booming, expected to reach $1.64 trillion
by 2032.
By Sayan Kundu

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Historical Development
1
Early Draw Frames
Manually operated machines were the
beginning.
2
1730: Lewis Paul
Patented drawing rollers.
3
1857: Heilmann
Rectilinear Comb invented
4
Today
Complex automated systems.
Draw frames evolved from simple manual machines to complex automated systems. Key innovations include drafting systems and
auto-levelers. These milestones shaped modern draw frame technology.
By Sayan Kundu

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❑ Draw Frame contributes less than 5% production cost of the yarn.
❑ It influence on quality, evenness and others
❑ If the draw frame is not properly adjusted there will also be effect on yarn strength and elongation
❑ If any defect arise, that affect on overall process
Currently, The Modern Draw Frame machine has ablity to produce 200kg of sliver per Hour
By Sayan Kundu

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Key Functions
Doubling
Combines slivers to average
variations (e.g., 6-8 slivers).
Parallelization
Aligns fibers, increasing yarn
strength.
Blending
Mixes fibers for desired
properties (e.g.,
cotton/polyester).
Leveling
Reduces sliver weight
variations (CV% from 4-6% to
1-2%).
The draw frame performs doubling, parallelization, blending, and leveling. Blending 60% cotton with 40% polyester enhances
durability. Leveling reduces sliver CV% from 4-6% to 1-2%.
By Sayan Kundu

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The value of θ is greater than 0 degree here with x axis The value of θ is exactly 0 degree here with x axis
If the force is applied in the direction of x axis then the Cosine value will be greater in case of Second one,
because it increases with the decrease of angle .
So, we can tell the length contribution on the strength in case of 2nd one that is due to the parallelization
(Happens in Draw Frame) is much more.
By Sayan Kundu

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Drafting and Auto-Leveling
Drafting Action
Sliver elongation is controlled by rollers
at varying speeds.
Roller Pairs
3-4 pairs increase speed to thin the
sliver.
Auto-Leveling
Continuously monitors and corrects
sliver weight. Feedback system adjusts
roller speeds based on sensor data.
Sliver CV% reduces by up to 50%.
By Sayan Kundu

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Machine Components
1 Feed Rollers
Control sliver input.
2 Drafting Zone
Thins and parallelizes fibers.
3 Sensors
Detect sliver thickness variations.
4 Coiler
Deposits drafted sliver into a can.
Key components are feed rollers, drafting zone, sensors, and coiler. The coiling speed reaches up to 800 m/min.
By Sayan Kundu

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Schematic Diagram of Draw Frame Machine
By Sayan Kundu

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Process Overview
Fiber Straightening
Fibers align upon entry.
Drafting
Sliver thins gradually.
Sliver Uniformity
Consistent weight and distribution.
The process involves fiber straightening, drafting, and achieving sliver uniformity. Typical draft ratios range from 6 to 12, with a
target sliver weight deviation of ± 1-2%.
By Sayan Kundu

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Drafting Arrangement
3 over 3
5 over 4
4 over 3
3 over 4
By Sayan Kundu

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Type of Drafting Rollers
Top Drafting Rollers
➢ Coated with material made by rubber
➢ Gives greater gripping during the time of material passing
➢ Prevent from slippage
By Sayan Kundu

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Bottom Drafting Rollers
Design is made to prevent from slippage
In case of simple 3 over 3 Drafting arrangements generally,
Axial Flutes presents in Middle Drafting roller
Helical Flutes presents in Back Drafting roller
Knurl Flutes presents in Front Drafting roller
Axial Flutes Helical Flutes Knurled Flutes
By Sayan Kundu

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Types of Draw Frames
Breaker Draw Frame
First stage, handles coarser slivers, and
reduces fiber mass.
Finisher Draw Frame
Second stage, processes finer slivers for
improved uniformity, preparing for spinning.
By Sayan Kundu

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Advances in Technology
Automated Sliver Handling
Robotic systems for can changes.
Real-Time Monitoring
Data analytics for optimization.
Servo-Driven Systems
Precise roller control. Improving U% by 10-15%
Integrated Control
Automatic defect detection. Industry 4.0 Integration
Modern draw frames feature automated handling, real-time monitoring, and servo-driven systems. These improve efficiency and
product quality. Industry 4.0 enables remote control.
By Sayan Kundu

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Conclusion
The draw frame is critical for high-quality, uniform yarn. Benefits include improved
strength, evenness, and dyeability. Technology advancements drive efficiency. The
global textile machinery market is projected to reach $35 billion by 2027.
By Sayan Kundu