The presentation is covered from history to advancements, from defects to their remedies. A little background study is needed to understand the presentation.
The document discusses the process of rolling metals. It begins by defining rolling as the plastic deformation of materials caused by compressive force applied through revolving rolls, which reduces the thickness and increases the length of the workpiece. It then discusses hot rolling and cold rolling processes. Hot rolling is performed above the recrystallization temperature and allows for large deformation, while cold rolling is used for finished sheets and plates. The document also covers grain structure changes during rolling, mechanics of rolling including forces, entry conditions, and roll pressure distribution. It concludes with discussing types of rolling mills.
Rolling is a metal forming process that reduces thickness or changes the cross-section of metal stock by compressive forces from rolls. There are two main types: flat rolling and shape rolling. Rolling can be done hot or cold depending on the temperature of the metal. Key rolling mill configurations include two-high, three-high, and four-high mills. Seamless pipes and tubes are formed through continuous processes without any welds, providing more reliable pressure retention than welded alternatives.
The document discusses the rolling process for metal forming. Rolling is defined as passing metal between rolls to plastically deform it. There are two main types: hot rolling, which is used for initial breakdown of ingots, and cold rolling, which provides closer dimensional tolerances and better surface finishes. Rolling can produce products like plate, sheet, strip, bars, and pipes. The rolling process involves passing metal through sets of rolls under high compressive forces.
Automatic gauge control (AGC) regulates the thickness at a mill's exit by monitoring thickness and controlling the loading cylinder to achieve the target thickness. AGC relies on thickness feed-forward control using the entry thickness, thickness feedback control based on exit thickness measurements, mass flow control, and speed feed-forward control. The thickness feedback control strategy measures thickness deviations at the exit and uses a predictive model to improve response times given delays between the roll gap and thickness gauge. Thickness feed-forward control further improves accuracy by compensating for deviations caused by changing entry thicknesses.
The document provides information about a 6 high reversible cold rolling mill, including:
1. Schematic diagrams and descriptions of the mill components including work rolls, intermediate rolls, back up rolls, uncoilers, recoilers, and tension reels.
2. Specifications for the mill such as thickness reduction capabilities, width tolerances, tension limits, and roll dimensions and frequencies.
3. Descriptions of equipment used in the mill like the pay off reel, three roll feeder, entry and delivery tension reels, and the roll changing car.
4. Explanations of concepts like roll deflection, shape definition, and types of defects that can occur like rust, coolant patches
This document discusses various metal forming processes including rolling, forging, extrusion, drawing, and shearing. It covers bulk deformation processes like rolling, forging, and extrusion which involve large plastic deformation and changing the cross-section without changing the volume. It also discusses sheet metal processes and categorizes the forming processes based on temperature into cold, warm and hot working. Key rolling processes like flat rolling, thread rolling and ring rolling are described along with forging and extrusion processes.
This document discusses various metal forming rolling processes. It defines rolling as plastically deforming metal by passing it between rolls. There are different types of rolling processes including transverse, shaped, skew, ring, thread, tube, powder, and continuous casting and hot rolling. It also describes the classification and purposes of processes like transverse, shaped, skew, ring, thread, and tube rolling. Finally, it discusses sheet rolling processes including hot and cold rolling.
Rotary forging is a combination of two actions, rotational and an axial compression movement, for precise component forming that can be carried out cold or hot
The document discusses the process of rolling metals. It begins by defining rolling as the plastic deformation of materials caused by compressive force applied through revolving rolls, which reduces the thickness and increases the length of the workpiece. It then discusses hot rolling and cold rolling processes. Hot rolling is performed above the recrystallization temperature and allows for large deformation, while cold rolling is used for finished sheets and plates. The document also covers grain structure changes during rolling, mechanics of rolling including forces, entry conditions, and roll pressure distribution. It concludes with discussing types of rolling mills.
Rolling is a metal forming process that reduces thickness or changes the cross-section of metal stock by compressive forces from rolls. There are two main types: flat rolling and shape rolling. Rolling can be done hot or cold depending on the temperature of the metal. Key rolling mill configurations include two-high, three-high, and four-high mills. Seamless pipes and tubes are formed through continuous processes without any welds, providing more reliable pressure retention than welded alternatives.
The document discusses the rolling process for metal forming. Rolling is defined as passing metal between rolls to plastically deform it. There are two main types: hot rolling, which is used for initial breakdown of ingots, and cold rolling, which provides closer dimensional tolerances and better surface finishes. Rolling can produce products like plate, sheet, strip, bars, and pipes. The rolling process involves passing metal through sets of rolls under high compressive forces.
Automatic gauge control (AGC) regulates the thickness at a mill's exit by monitoring thickness and controlling the loading cylinder to achieve the target thickness. AGC relies on thickness feed-forward control using the entry thickness, thickness feedback control based on exit thickness measurements, mass flow control, and speed feed-forward control. The thickness feedback control strategy measures thickness deviations at the exit and uses a predictive model to improve response times given delays between the roll gap and thickness gauge. Thickness feed-forward control further improves accuracy by compensating for deviations caused by changing entry thicknesses.
The document provides information about a 6 high reversible cold rolling mill, including:
1. Schematic diagrams and descriptions of the mill components including work rolls, intermediate rolls, back up rolls, uncoilers, recoilers, and tension reels.
2. Specifications for the mill such as thickness reduction capabilities, width tolerances, tension limits, and roll dimensions and frequencies.
3. Descriptions of equipment used in the mill like the pay off reel, three roll feeder, entry and delivery tension reels, and the roll changing car.
4. Explanations of concepts like roll deflection, shape definition, and types of defects that can occur like rust, coolant patches
This document discusses various metal forming processes including rolling, forging, extrusion, drawing, and shearing. It covers bulk deformation processes like rolling, forging, and extrusion which involve large plastic deformation and changing the cross-section without changing the volume. It also discusses sheet metal processes and categorizes the forming processes based on temperature into cold, warm and hot working. Key rolling processes like flat rolling, thread rolling and ring rolling are described along with forging and extrusion processes.
This document discusses various metal forming rolling processes. It defines rolling as plastically deforming metal by passing it between rolls. There are different types of rolling processes including transverse, shaped, skew, ring, thread, tube, powder, and continuous casting and hot rolling. It also describes the classification and purposes of processes like transverse, shaped, skew, ring, thread, and tube rolling. Finally, it discusses sheet rolling processes including hot and cold rolling.
Rotary forging is a combination of two actions, rotational and an axial compression movement, for precise component forming that can be carried out cold or hot
Metal forming processes use plastic deformation to change the shape of metal workpieces. Rolling is one of the most common metal forming processes, accounting for around 90% of metal shaping. In rolling, the metal workpiece is passed through one or more sets of rolls, reducing the thickness and changing the cross-sectional area under compressive forces applied by the rolls. The geometry of the final product is determined by the shape and contour of the roll gap. Rolling can be performed hot or cold, and is used to produce a wide variety of parts for structural applications and transportation.
This document provides information on bending theory and design principles for bending operations. It discusses the following key points in 3 sentences:
Types of bending covered include V-bending, edge bending, and flanging. Springback occurs as the bent part partially recovers its original shape after bending forces are removed. The document outlines methods to compensate for springback like overbending and bottoming, and provides formulas to estimate springback and calculate bending allowance and force.
This document discusses various sheet metal forming processes. It covers shearing operations like punching and blanking. It also discusses bending and drawing operations and how they deform sheet metal. Finally, it introduces special forming processes like hydroforming, rubber pad forming, spinning and explosive forming that can form sheet metal into more complex shapes.
Bend Tooling Inc. provides rotary-draw tube bending tools including die sets, mandrels, wipers, and mandrel bending tools. The document defines various tube bending terminology related to tooling components and the bending process. Key terms defined include clamp die, compound clamp, line of tangency, mandrel, mandrel assembly, mandrel nose, neutral axis, and wiper.
Rolling is a metal forming process where metal stock is passed through one or more pairs of rotating rollers to reduce the thickness and change the cross-section of the metal. There are two main types of rolling: hot rolling, where the temperature of the metal is above the recrystallization temperature, and cold rolling, where the temperature is below the recrystallization temperature. To avoid bending during rolling, the surface velocity of the top and bottom rollers must be equal. There are several types of rolling mills including two high, three high, four high, cluster, and tandem mills which differ in their roller configurations and applications. Rolling is used to mass produce a variety of products like sheets, rods, tubes, bol
Metal forming processes can be classified as either plastic deformation processes, where the volume and mass of metals are unchanged, such as rolling, forging, and extrusion, or metal removal processes, where material is removed from the metal, such as turning and thread cutting. Rolling is a process where the thickness or cross-section of metal is reduced by passing it between rolls and can be classified as either hot rolling, above the metal's recrystallization temperature, or cold rolling, below the recrystallization temperature. Recrystallization is a process where a distorted grain structure is replaced by a new stress-free structure through heating and deformation above a minimum temperature, reducing strength and raising ductility.
This document provides an overview of forging and press working processes. It defines forging as plastically deforming metal under compressive force at elevated temperatures using tools like hammers or presses. Forging is classified as open die or closed die based on the tools used, and as hammer, press, drop or machine forging based on the equipment. Press working involves shaping sheet metal between dies in a press machine. Common press working operations include cutting via blanking, punching and forming through bending and drawing.
The document discusses the rolling process used in metal forming. It describes rolling as a process where the thickness of metal is reduced by compressive forces from two opposing rolls. Rolling can be used for flat rolling to reduce thickness of rectangular cross-sections or shape rolling to form square cross-sections into shapes like I-beams. The document outlines different types of rolling like hot rolling, cold rolling, continuous rolling and shape rolling and describes the purposes and processes for each type.
Basics of Tube Bending explores the fundamentals of bending with a mandrel, bending tube with a plug mandrel, a ball mandrel and wiper die, and also explores and troubleshoots some of the most common tube bending problems and issues!
This document provides a 10-step overview of the cold rolling process for steel in a 4 Hi mill. The key steps include: 1) Pickling the hot rolled coil to remove impurities, 2) Water washing, 3) Applying a rust-protective emulsion, 4) Sizing coils to an ideal diameter for rolling, 5) Cold rolling the steel through multiple passes to reduce thickness, 6) Annealing to improve strength, 7) A final "skin pass" rolling, 8) Slitting coils to customer specifications, 9) Applying a protective coating, and 10) Packaging the finished cold rolled steel for shipping. The cold rolled steel can be used for automotive and appliance manufacturing.
This document summarizes the metal forming process of rolling. It describes how rolling works by passing metal between rolls, subjecting it to compressive and shear stresses. It discusses different types of rolling mills and explains how hot and cold rolling differ, with hot rolling reducing size at high temperatures and cold rolling providing better surface finish. The document also outlines defects that can occur during rolling such as surface irregularities, inclusions, and edge cracking or center splitting.
This document provides information about cold rolling mills and the cold rolling process. It discusses:
- The basic components and functions of cold rolling mills, which refine the surface and improve properties of hot-rolled steel coils.
- The differences between hot and cold rolling processes, with cold rolling providing closer tolerances and a wider range of finishes.
- A flow chart outlining the key steps in cold rolling, including roll bending, additional bending, anti-bending, roll gap adjustment, and profile regulation using zone cooling.
The document discusses the rolling process used in mechanical engineering. It begins with introductions and terminology for rolling. It then covers classifications of rolling mills like two high, three high, and four high mills. The types of rolling processes discussed include conventional, transverse, shaped, ring, powder, and thread rolling. Hot and cold rolling are also covered. Key aspects of the rolling process like roll bite condition and common rolling defects are defined. The document concludes with potential problems in rolling and sample multiple choice questions.
Upset forging is a forging process that increases the diameter of a workpiece like wire or rod by compressing its length using high-speed machines, with standard machines using split dies containing multiple cavities. The process involves the dies opening to move the workpiece between cavities, then closing as a ram moves against the workpiece to upset it into the cavity shape, allowing finished parts to be produced on each cycle for mass production of items like engine valves, bolts, and screws.
The document discusses three types of bending that occur when sheet metal is bent: partial bending, bottoming, and coining. It explains the relationship between bending force and bending angle through an S-curve diagram. Partial bending and bottoming occur through air bending with relatively low force, while coining requires much higher force and eliminates springback for greater precision. Springback occurs due to the material retaining elasticity even after yielding. The document also discusses bottoming as the most common air bending technique, providing a table relating sheet thickness to optimal V-width for the die.
1. The document discusses sheet metal forming processes including shearing, bending, and springback. It provides definitions and formulas for calculating forces in shearing and springback in bending.
2. An lab experiment is described that involves bending aluminum strips using a finger brake machine and measuring the resulting bend radii and angles to analyze springback.
3. Finite element analysis simulations are shown illustrating the deformation during bending and springback.
Rolling is a metalworking process that reduces thickness by passing metal between rolls. It is commonly used to convert steel ingots into thinner slabs, sheets, and strips. There are different types of rolling including hot, cold, and shape rolling. Hot rolling above the recrystallization temperature allows for large reductions while cold rolling below this temperature produces better surface finishes. Rolling processes are used widely in Pakistan's steel industry by companies like Batala Steel Products and Mughal Steel to manufacture items like pipes, storage tanks, and steel flooring.
Rolling is a metal forming process where metal stock is passed through one or more pairs of rolls to reduce the thickness and change the cross section of the metal. There are both hot and cold rolling processes. The metal is compressed between the rolls through frictional forces, changing the shape of the metal. Rolling processes can produce shapes like plates, sheets, rods, bars, pipes and rails. Rolling mills can have two, three, four or multiple rolls depending on the specific application and required shape. Rolling is used to mass produce metal products and form complex cross sections.
This document discusses the selection of forging equipment and stock size for open and closed die forging. It begins by classifying forging equipment into work-restricted and stroke-restricted machines such as hammers, presses, and hydraulic presses. It then explains open and closed die forging processes and considerations for die design such as flash, gutter, draft angles, and variation of stroke with load. The document concludes by providing design considerations for blocker, finisher, trim tools, and punches.
The document discusses various metal forming processes including rolling, forging, extrusion, and sheet metal working. It provides details on:
- Hot and cold working processes for forming metals like rolling, forging, and extrusion. These processes involve changing the shape of metals above or below their recrystallization temperature.
- Different types of rolling mills and how rolling changes the grain structure and properties of metals.
- The basic process of extrusion using direct or indirect methods to form materials into fixed cross-sections.
- Common forming techniques like deep drawing, bending, spinning, and drawing used to work sheet metals.
The document discusses various types of rolling processes including hot rolling, cold rolling, ring rolling, sheet rolling, roll forming, roll bending, shape rolling, pack rolling, thread rolling, roll piercing, and planetary mill rolling. It provides definitions and descriptions of each process. It also discusses related topics like geometry of rolling processes, lubrication, defects in rolling, and formulas used in rolling calculations.
Metal forming processes use plastic deformation to change the shape of metal workpieces. Rolling is one of the most common metal forming processes, accounting for around 90% of metal shaping. In rolling, the metal workpiece is passed through one or more sets of rolls, reducing the thickness and changing the cross-sectional area under compressive forces applied by the rolls. The geometry of the final product is determined by the shape and contour of the roll gap. Rolling can be performed hot or cold, and is used to produce a wide variety of parts for structural applications and transportation.
This document provides information on bending theory and design principles for bending operations. It discusses the following key points in 3 sentences:
Types of bending covered include V-bending, edge bending, and flanging. Springback occurs as the bent part partially recovers its original shape after bending forces are removed. The document outlines methods to compensate for springback like overbending and bottoming, and provides formulas to estimate springback and calculate bending allowance and force.
This document discusses various sheet metal forming processes. It covers shearing operations like punching and blanking. It also discusses bending and drawing operations and how they deform sheet metal. Finally, it introduces special forming processes like hydroforming, rubber pad forming, spinning and explosive forming that can form sheet metal into more complex shapes.
Bend Tooling Inc. provides rotary-draw tube bending tools including die sets, mandrels, wipers, and mandrel bending tools. The document defines various tube bending terminology related to tooling components and the bending process. Key terms defined include clamp die, compound clamp, line of tangency, mandrel, mandrel assembly, mandrel nose, neutral axis, and wiper.
Rolling is a metal forming process where metal stock is passed through one or more pairs of rotating rollers to reduce the thickness and change the cross-section of the metal. There are two main types of rolling: hot rolling, where the temperature of the metal is above the recrystallization temperature, and cold rolling, where the temperature is below the recrystallization temperature. To avoid bending during rolling, the surface velocity of the top and bottom rollers must be equal. There are several types of rolling mills including two high, three high, four high, cluster, and tandem mills which differ in their roller configurations and applications. Rolling is used to mass produce a variety of products like sheets, rods, tubes, bol
Metal forming processes can be classified as either plastic deformation processes, where the volume and mass of metals are unchanged, such as rolling, forging, and extrusion, or metal removal processes, where material is removed from the metal, such as turning and thread cutting. Rolling is a process where the thickness or cross-section of metal is reduced by passing it between rolls and can be classified as either hot rolling, above the metal's recrystallization temperature, or cold rolling, below the recrystallization temperature. Recrystallization is a process where a distorted grain structure is replaced by a new stress-free structure through heating and deformation above a minimum temperature, reducing strength and raising ductility.
This document provides an overview of forging and press working processes. It defines forging as plastically deforming metal under compressive force at elevated temperatures using tools like hammers or presses. Forging is classified as open die or closed die based on the tools used, and as hammer, press, drop or machine forging based on the equipment. Press working involves shaping sheet metal between dies in a press machine. Common press working operations include cutting via blanking, punching and forming through bending and drawing.
The document discusses the rolling process used in metal forming. It describes rolling as a process where the thickness of metal is reduced by compressive forces from two opposing rolls. Rolling can be used for flat rolling to reduce thickness of rectangular cross-sections or shape rolling to form square cross-sections into shapes like I-beams. The document outlines different types of rolling like hot rolling, cold rolling, continuous rolling and shape rolling and describes the purposes and processes for each type.
Basics of Tube Bending explores the fundamentals of bending with a mandrel, bending tube with a plug mandrel, a ball mandrel and wiper die, and also explores and troubleshoots some of the most common tube bending problems and issues!
This document provides a 10-step overview of the cold rolling process for steel in a 4 Hi mill. The key steps include: 1) Pickling the hot rolled coil to remove impurities, 2) Water washing, 3) Applying a rust-protective emulsion, 4) Sizing coils to an ideal diameter for rolling, 5) Cold rolling the steel through multiple passes to reduce thickness, 6) Annealing to improve strength, 7) A final "skin pass" rolling, 8) Slitting coils to customer specifications, 9) Applying a protective coating, and 10) Packaging the finished cold rolled steel for shipping. The cold rolled steel can be used for automotive and appliance manufacturing.
This document summarizes the metal forming process of rolling. It describes how rolling works by passing metal between rolls, subjecting it to compressive and shear stresses. It discusses different types of rolling mills and explains how hot and cold rolling differ, with hot rolling reducing size at high temperatures and cold rolling providing better surface finish. The document also outlines defects that can occur during rolling such as surface irregularities, inclusions, and edge cracking or center splitting.
This document provides information about cold rolling mills and the cold rolling process. It discusses:
- The basic components and functions of cold rolling mills, which refine the surface and improve properties of hot-rolled steel coils.
- The differences between hot and cold rolling processes, with cold rolling providing closer tolerances and a wider range of finishes.
- A flow chart outlining the key steps in cold rolling, including roll bending, additional bending, anti-bending, roll gap adjustment, and profile regulation using zone cooling.
The document discusses the rolling process used in mechanical engineering. It begins with introductions and terminology for rolling. It then covers classifications of rolling mills like two high, three high, and four high mills. The types of rolling processes discussed include conventional, transverse, shaped, ring, powder, and thread rolling. Hot and cold rolling are also covered. Key aspects of the rolling process like roll bite condition and common rolling defects are defined. The document concludes with potential problems in rolling and sample multiple choice questions.
Upset forging is a forging process that increases the diameter of a workpiece like wire or rod by compressing its length using high-speed machines, with standard machines using split dies containing multiple cavities. The process involves the dies opening to move the workpiece between cavities, then closing as a ram moves against the workpiece to upset it into the cavity shape, allowing finished parts to be produced on each cycle for mass production of items like engine valves, bolts, and screws.
The document discusses three types of bending that occur when sheet metal is bent: partial bending, bottoming, and coining. It explains the relationship between bending force and bending angle through an S-curve diagram. Partial bending and bottoming occur through air bending with relatively low force, while coining requires much higher force and eliminates springback for greater precision. Springback occurs due to the material retaining elasticity even after yielding. The document also discusses bottoming as the most common air bending technique, providing a table relating sheet thickness to optimal V-width for the die.
1. The document discusses sheet metal forming processes including shearing, bending, and springback. It provides definitions and formulas for calculating forces in shearing and springback in bending.
2. An lab experiment is described that involves bending aluminum strips using a finger brake machine and measuring the resulting bend radii and angles to analyze springback.
3. Finite element analysis simulations are shown illustrating the deformation during bending and springback.
Rolling is a metalworking process that reduces thickness by passing metal between rolls. It is commonly used to convert steel ingots into thinner slabs, sheets, and strips. There are different types of rolling including hot, cold, and shape rolling. Hot rolling above the recrystallization temperature allows for large reductions while cold rolling below this temperature produces better surface finishes. Rolling processes are used widely in Pakistan's steel industry by companies like Batala Steel Products and Mughal Steel to manufacture items like pipes, storage tanks, and steel flooring.
Rolling is a metal forming process where metal stock is passed through one or more pairs of rolls to reduce the thickness and change the cross section of the metal. There are both hot and cold rolling processes. The metal is compressed between the rolls through frictional forces, changing the shape of the metal. Rolling processes can produce shapes like plates, sheets, rods, bars, pipes and rails. Rolling mills can have two, three, four or multiple rolls depending on the specific application and required shape. Rolling is used to mass produce metal products and form complex cross sections.
This document discusses the selection of forging equipment and stock size for open and closed die forging. It begins by classifying forging equipment into work-restricted and stroke-restricted machines such as hammers, presses, and hydraulic presses. It then explains open and closed die forging processes and considerations for die design such as flash, gutter, draft angles, and variation of stroke with load. The document concludes by providing design considerations for blocker, finisher, trim tools, and punches.
The document discusses various metal forming processes including rolling, forging, extrusion, and sheet metal working. It provides details on:
- Hot and cold working processes for forming metals like rolling, forging, and extrusion. These processes involve changing the shape of metals above or below their recrystallization temperature.
- Different types of rolling mills and how rolling changes the grain structure and properties of metals.
- The basic process of extrusion using direct or indirect methods to form materials into fixed cross-sections.
- Common forming techniques like deep drawing, bending, spinning, and drawing used to work sheet metals.
The document discusses various types of rolling processes including hot rolling, cold rolling, ring rolling, sheet rolling, roll forming, roll bending, shape rolling, pack rolling, thread rolling, roll piercing, and planetary mill rolling. It provides definitions and descriptions of each process. It also discusses related topics like geometry of rolling processes, lubrication, defects in rolling, and formulas used in rolling calculations.
The document discusses the metal forming process of rolling. It involves passing hot or cold metal through heavy rolls to reduce thickness and increase length. There are two main types - hot rolling above the metal's recrystallization temperature and cold rolling at room temperature. The grain structure changes as the metal is compressed and different rolling mill designs are used for different applications, including two-high, three-high, and cluster mills. The rolling process involves reducing thickness through multiple passes to achieve the final shape and dimensions.
The document summarizes the rolling process. It defines rolling as plastically deforming metal by passing it between rolls. Rolling provides close dimensional control and high production. There are two main types: hot rolling and cold rolling. The document describes various rolling terminologies, mill products, defects, and different rolling processes like hot rolling, cold rolling, shaped rolling, and thread rolling. It also discusses factors like angle of contact, forces involved, and how to control flatness.
Rolling is a metal forming process where metal stock is passed through one or more pairs of rolls to reduce the thickness and increase the length. There are two main types:
1) Hot rolling is performed above the metal's recrystallization temperature for lower pressure and improved ductility. It produces coarse grains and no residual stresses.
2) Cold rolling is performed below the recrystallization temperature, requiring higher pressures but improving dimensions, finish and strength through residual stresses and elongated grains.
Rolling mills are classified by the number of rolls used, including two-high, three-high, four-high and cluster/sendzimir mills. Continuous mills use multiple stands to continuously roll sheet metal.
Roll forming is a metal forming process that uses pairs of rolls to progressively bend and form sheet metal, tubes, or strips into the desired cross-sectional shape. It is commonly used to form lightweight metals like aluminum into strong, rigid parts. The roll forming process strengthens the material and improves properties like hardness and corrosion resistance. Flat rolling is the most widely used metal forming process, accounting for around 90% of forming. It involves passing slabs, strips, sheets, or plates between rolls to reduce thickness and possibly increase width. The workpiece is squeezed between the rolls, reducing thickness through compression. Friction plays an important role in drawing the workpiece into the roll gap for forming. High velocity hydroforming uses high-pressure
Roll forming is a metal forming process that uses pairs of rolls to progressively bend and form sheet metal, tubes, or strips into the desired cross-sectional shape. It is commonly used to form lightweight metals like aluminum into strong, rigid parts. The roll forming process strengthens the material and improves properties like hardness and corrosion resistance. Flat rolling is the most widely used metal forming process, accounting for around 90% of forming. It involves passing slabs, strips, sheets, or plates between rolls to reduce thickness and possibly increase width. The workpiece is squeezed between the rolls, reducing thickness through compression. Friction plays an important role in drawing the workpiece into the roll gap for forming. High velocity hydroforming uses high-pressure
This document provides an overview of various metal forming processes including rolling, extrusion, drawing, forging, bending, punching, blanking, deep drawing, and stretch forming. It discusses the basic mechanisms, types, defects, and forces involved in each process. Key points covered include how rolling reduces thickness through plastic deformation between rolls, the differences between direct and indirect extrusion, how drawing reduces cross-sectional area by pulling metal through a die, and common defects that can occur in deep drawing like wrinkling, tearing, and earing.
This document provides information on various sheet metal forming processes. It discusses the characteristics of sheet metal and tests used to determine formability. The main sheet metal forming processes covered are tube bending and forming as well as bending of sheet and plate. Tube bending can be done via press bending, rotary drawing, heat induction, roll bending, and sand packing. Sheet and plate bending includes techniques like roll bending, air bending, bottoming, coining, folding, wiping, and rotary bending. Common applications of sheet metal forming in industries like automotive, aircraft, appliances, and furniture are also mentioned.
Forging is the process of shaping metals by applying compressive forces. It can be done either hot or cold. Common forging operations include drawing, piercing, punching, and swaging. Forging machines include drop hammers, power hammers, mechanical presses, and hydraulic presses. Closed-die forging uses dies to precisely shape parts, while open-die forging uses simpler dies. Proper die material selection and coatings can increase die life. Forging results in an elongated grain structure and improved mechanical properties compared to casting.
The document discusses various aspects of rolling processes. It defines rolling as a metalworking process that uses compressive forces exerted by rolls to reduce the thickness or change the cross-section of a workpiece. It describes the basic components of a rolling mill and the functions of rolls. It also discusses types of rolling like flat rolling, shape rolling, ring rolling, and thread rolling. Key differences between hot and cold rolling are explained along with advantages and disadvantages of each. Various products produced from rolling like plates, sheets, strips are also mentioned.
Sheet metal working for non ferrous metal and alloysNikunj Patel
its sheet metal working for non ferrous metal and alloy. its show all process like punching, deep drawing, etc which can employ in sheet metal working.its show how process done in short details.
Forging processes involve shaping metals by applying compressive forces. There are four main types: hammer/drop forging uses gravity impacts, press forging uses hydraulic or mechanical presses, and open-die and closed-die forging differ in whether dies fully contain the metal. Forging increases strength by working the metal and altering its microstructure. Proper die and process design are needed to control metal flow, fill dies completely, and minimize flash and defects. Die materials must withstand thermal and mechanical stresses, while coatings can extend die life.
This document discusses various metal forming and shaping processes, with a focus on rolling processes. It describes how rolling is used to reduce thickness and change the cross-section of metal workpieces. Rolling accounts for about 90% of all metals produced and involves passing metal between rotating rolls. Hot rolling at elevated temperatures is used to break down cast structures into wrought structures with improved properties. Cold rolling at room temperature produces parts with higher strength, hardness and surface finish. The document outlines various rolling processes like flat rolling, shape rolling, ring rolling and their associated equipment and applications in producing parts.
IIIE SECTION A MANUFACTURING TECHNOLOGY NOTES 7.centrifugal castingBhaskar Nagarajan
Centrifugal casting involves pouring molten metal into a revolving mold, which uses centrifugal force to push the metal against the mold walls where it solidifies. This allows for the mass production of hollow cylindrical parts like pipes. There are three main types: true centrifugal casting produces perfectly cylindrical parts using a hollow, rotating mold; semi-centrifugal casting uses a core to form an inner surface while still utilizing centrifugal force; and centrifuged casting applies high fluid pressure to force molten metal into molds of complex, non-symmetrical shapes. Centrifugal casting provides dense, clean castings and eliminates the need for runners, risers, and cores, but is limited to annular parts and involves high initial
This document discusses various metal forming processes including rolling, extrusion, forging, and drawing. It provides definitions and descriptions of each process. Rolling involves passing metal through rotating rolls to reduce thickness or shape it. Extrusion uses a press to force heated metal through a die to shape it. Forging shapes heated metal by compressing it with dies or hammers. Drawing shapes metal by pulling it through a die to reduce its cross-sectional area. Each process deforms metal through compression or tension to form parts.
This document discusses the process of continuous casting of steel. It begins with an introduction and overview of the process. It then describes the three main types of continuous casting machines - vertical mould, vertical mould with bending, and curved mould. It provides details on the equipment, materials, process steps, defects, and modern developments of continuous casting. Some advantages are improved yield, quality, productivity and cost efficiency compared to ingot casting. Disadvantages include the need for a large facility and efficient cooling.
its sheet metal working for non ferrous metal and alloy. its show all process like punching, deep drawing, etc which can employ in sheet metal working.its show how process done in short details.
This document discusses various metal forming processes including forging, rolling, drawing, and extrusion. It provides details on:
1) Hot and cold working of metals, types of forging processes, characteristics of forging, types of forging machines, and common forging operations.
2) Types of rolling mills and rolling processes like flat strip rolling and shape rolling. It also discusses defects in rolled parts.
3) Principles and types of drawing and extrusion processes. Drawing processes include wire, rod, tube, and deep drawing. Extrusion can be hot or cold.
Null Bangalore | Pentesters Approach to AWS IAMDivyanshu
#Abstract:
- Learn more about the real-world methods for auditing AWS IAM (Identity and Access Management) as a pentester. So let us proceed with a brief discussion of IAM as well as some typical misconfigurations and their potential exploits in order to reinforce the understanding of IAM security best practices.
- Gain actionable insights into AWS IAM policies and roles, using hands on approach.
#Prerequisites:
- Basic understanding of AWS services and architecture
- Familiarity with cloud security concepts
- Experience using the AWS Management Console or AWS CLI.
- For hands on lab create account on [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
# Scenario Covered:
- Basics of IAM in AWS
- Implementing IAM Policies with Least Privilege to Manage S3 Bucket
- Objective: Create an S3 bucket with least privilege IAM policy and validate access.
- Steps:
- Create S3 bucket.
- Attach least privilege policy to IAM user.
- Validate access.
- Exploiting IAM PassRole Misconfiguration
-Allows a user to pass a specific IAM role to an AWS service (ec2), typically used for service access delegation. Then exploit PassRole Misconfiguration granting unauthorized access to sensitive resources.
- Objective: Demonstrate how a PassRole misconfiguration can grant unauthorized access.
- Steps:
- Allow user to pass IAM role to EC2.
- Exploit misconfiguration for unauthorized access.
- Access sensitive resources.
- Exploiting IAM AssumeRole Misconfiguration with Overly Permissive Role
- An overly permissive IAM role configuration can lead to privilege escalation by creating a role with administrative privileges and allow a user to assume this role.
- Objective: Show how overly permissive IAM roles can lead to privilege escalation.
- Steps:
- Create role with administrative privileges.
- Allow user to assume the role.
- Perform administrative actions.
- Differentiation between PassRole vs AssumeRole
Try at [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
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1. Malaviya National Institute of Technology Jaipur
#Conclave of Rolling Processes#
Submitted by
Basitti Hitesh
2017PMT5094
2. Early equipment for metal rolling
The equipment that followed to create sheet products proved
to be of very simple design.
It is not known who created the first rolling mill. However, one
of the earliest drawings is by Leonardo da Vinci. It even shows
the need for larger diameter backup rolls to support longer,
smaller diameter work rolls as shown in the fig.
15th – 17th century
In the middle of the fifteenth century small mills produced gold
lace, and other decorative work, in soft metals.
There is evidence for rolling of lead and tin on simple 2-high
mills with cast-iron rolls at the beginning of the seventeenth
century.
6. Definition of Rolling Process
The process of plastically deforming metal by passing it between rolls
is known as Rolling.
Rolling is a process of reducing the thickness (or changing the cross-
section) of a long work piece by compressive forces applied through
a set of rolls.
Rolling is a metal forming process in which stock is passed through
one or more pairs of rolls to reduce the thickness and to make
thickness uniform.
7. Rolling Process
Hot Rolling Cold Rolling
Done above Recrystallization Temperature (Tᵣ) Done below Room temperature
8. Typical arrangement of rollers for rolling mills
Two High Mill,(Pull over)
The stock is returned to the entrance for
further reduction
9. Typical arrangement of rollers for rolling mills
Two High Mill (Reversing)
The work can be passed back and forth through the rolls
by reversing their direction of rotation.
10. Typical arrangement of rollers for rolling mills
Three High Rolling Mill
Consists of Upper and Lower driven rolls and a middle roll,
which rotates by friction.
11. Typical arrangement of rollers for rolling mills
This is based on the principle that small-diameter rolls lower the
roll forces and reduce Spreading.
Moreover, when worn or broken, small rolls can be replaced at less
cost than can large ones.
However, small rolls deflect more under roll forces and have to be
supported by other rolls.
13. Typical arrangement of rollers for rolling mills
Cluster (Sendzimir) Mill
Each of the work rolls is supported by two backing rolls.
Although the cost of a Sendzimir mill facility can be millions of dollars, it is
particularly suitable for cold rolling thin sheet of High-Strength metals.
14. Typical arrangement of rollers for rolling mills
Continuous (Tandem) Rolling Mill
• Here, uses a series of rolling mill and each set is called a stand.
• The strip will be moving at different velocity at each stage in the mill.
• Used for cold rolling of Steel sheets, Al, Cu alloys.
• High Capacity and low labor cost.
15. The speed of each set of rolls is synchronized so that the input speed of each stand is equal to the
output speed of preceding stand.
The uncoiler and wind up reel not only feed the stock into the rolls and coiling up the final
product but also provide back tension and front tension to the strip.
Tandem Rolling Mill (contd..)
16. Typical arrangement of rollers for rolling mills
Planetary rolling mill
• Consists of a pair of heavy backing rolls surrounded by a large no. of
planetary rolls.
• Each planetary rolls gives an almost constant reduction to the slab.
• As each pair of planetary rolls ceases to have contact with the work piece,
another pair of rolls makes contact and repeat that reduction.
• The overall reduction is the summation of a series of small reductions by
each pair of rolls. Therefore, the planetary mill can reduces a hot slab
directly to strip in one pass through the mill.
• The operation requires feed rolls to introduce the slab into the mill, and a
pair of planishing rolls on the exit to improve the surface finish.
18. Rolling Processes
• Continuous Rolling
• Transverse Rolling
• Shaped Rolling or Section Rolling
• Ring Rolling
• Powder Rolling
• Continuous Casting and Hot Rolling
• Thread Rolling
19. Continuous Rolling (Conventional Hot or Cold Rolling)
The objective is to decrease the thickness of the metal with an increase in
length and with little increase in width.
20. Transverse Rolling or Roll Forging or Cross Rolling
In this operation, the cross section of a round bar is shaped by
passing it through a pair of rolls with profiled grooves. Roll forging
typically is used to produce tapered shafts and leaf springs, table
knives, and hand tools.
Here, rolls are revolved in one direction.
21. Shaped Rolling or Section Rolling
A special type of cold rolling in which flat slab is progressively bent into
complex shapes by passing it through a series of driven rolls.
No appreciable change in the thickness of the metal during this process.
Suitable for producing molded sections such as irregular shaped channels
and trim.
22. Ring Rolling (Seamless rings)
Here, a thick ring is expanded into a large
diameter thinner one.
The ring is placed between two rolls, one of
the which is driven while the other is idle. Its
thickness is reduced by bringing the rolls closer
together as they rotate.
Typical applications are large rings for rockets
and turbines.
23.
24. Powder Rolling
Metal powder is introduced between the rolls and compacted
into a green strip, which is subsequently sintered and subjected
to further hot working and/or cold working and annealing
cycles.
Advantages
• Cut down the initial hot ingot breakdown step.
• Economical
• Minimize contamination in hot rolling.
• Provide fine grain size with a minimum of preferred
orientation.
25. Continuous casting and Hot Rolling
Metal is melted, cast and hot rolled continuously
through a series of rolling mills within the same
process.
Usually for steel sheet production.
26.
27. The main benefits from the direct rolling technology are:
Low Capital investment for main equipment in case of green field units.
Low Operational cost of rolled steel depending on unit costs
Low inventory and working-capital requirements
Reduced requirements of personnel / manpower.
Reduced civil works and infrastructure costs.
Reduced energy consumption.
Smooth mill operation due to consistent temperature of the input stock.
Higher product yield& consistent quality product.
Low CO2 emissions.
Saving of space.
Production of finished rolled products from scrap in lesser time.
28. Thread Rolling
Dies are pressed against the surface of cylindrical blank. As the
blank rolls against the in-feeding die faces, the material is displaced
to form the roots of the thread, and the displaced material flows
radially outward to form the thread’s crest.
The grain structure of the material is not cut, but is distorted to
follow the thread form.
Rolled threads are produced in a single pass at speeds far in excess of those
used to cut threads.
The resultant thread has a greater resistance to mechanical stress and an
increase in fatigue strength. Also the surface is burnished and work hardened.
29. Analysis of Rolling process
Assumptions
1. The arc of contact between the rolls and the metal is a part of a
circle.
2. The co-efficient of friction, ‘μ’ is constant in theory, but in reality ‘μ’
varies along the arc of contact.
3. The metal is considered to deform plastically during rolling.
4. The volume of metal is constant before and after rolling. In practical,
the volume might decrease a little bit due to close-up of pores.
5. The velocity of the rolls is assumed to be constant.
6. The metal only extends in the rolling direction and no extension in
the width of the material.
7. The cross sectional area normal to the rolling direction is not
distorted.
30. Since, there is no change in metal volume at a given pt.
per unit time throughout the process.
Where ‘b’ is the width of the sheet
‘v’ is the velocity of any thickness ‘h’ intermediate
between ho & hf
When ho ˃ hf, we then have vo ˂ vf
The velocity of the sheet must steadily increase from
entrance to exit such that a vertical element in the sheet
remain undistorted.
31. At a point along the surface of contact between
the roll and the sheet, two forces act on the
metal:
1) a radial force Pr and
2) a tangential frictional force F.
At one pt. along the contact length, called the Neutral
point or No slip point, the velocity of the strip is the same
as that of the roll.
To the left of this pt., the roll moves faster than the strip,
to the, to the right of this pt., the strip moves faster than
the roll.
32. Because the surface speed of the rigid roll is
constant, there is relative sliding between the roll
and the strip along the arc of contact in the roll
gap.
The amount of slip between the rolls and the work can
be measured by means of the forward slip, a term
used in rolling that is defined:
Where s = forward slip
vf = final (exiting) work velocity, m/s (ft/sec) and
vr = roll speed, m/s (ft/sec).
33. The roll pull the material into the roll gap through a net frictional force on the
material. It can be seen that this net frictional force must be to the right;
consequently, the frictional force to the left of the neutral pt. must higher than
the frictional force to the right.
For the workpiece to enter the throat of the roll, the component of the
friction force must be equal to or greater than the horizontal component of
the normal force.
But we know,
Therefore,
If tan α > μ, the workpiece cannot be drawn.
If μ = 0, rolling cannot occur.
Therefore Free engagement will occur when μ > tan α
34. The Maximum Reduction (Draft)
From triangle ABC, we have
As ‘a’ much smaller than ‘R’, we can ignore a².
Where ∆h=2a
35. The distribution of roll pressure along the arc of contact shows that the
pressure rises to a maximum at the neutral point and then falls off.
The pressure distribution does not come to a sharp peak at the neutral point,
which indicates that the neutral point is not really a line on the roll surface
but an area.
The area under the curve is proportional to the rolling load.
The area in shade represents the force required to overcome frictional forces
between the roll and the sheet.
The area under the dashed line AB represents the force required to
deform the metal in plane homogeneous compression.
The specific roll pressure, ‘p’ is the rolling load divided by the contact area.
36. Roll force Calculation
Note that this force appears in the figure as perpendicular to the plane of the strip,
rather than at an angle. This is because, in practice, the arc of contact is very small
compared with the roll radius, so we can assume that the roll force is perpendicular to
the strip without causing significant error in calculations. The roll force in flat rolling
can be estimated from the formula
Where = average flow stress, MPa (lb/in2); and the product (wL) is the roll-
work contact area, mm2 (in2).
37. The main variables in rolling are:
• The roll diameter.
• The deformation resistance of the metal as influenced by metallurgy, temperature and strain rate.
• The friction between the rolls and the workpiece.
• The presence of the front tension and/or back tension in the plane of the sheet.
We consider in three conditions:
1) No friction condition
2) Normal friction condition
3) Sticky friction condition
38. No friction situation
In the case of no friction situation, the rolling load (P)
is given by the roll pressure (p) times the area of contact
between the metal and the rolls (bLp).
Where the roll pressure (p) is the yield stress in plane strain
when there is no change in the width (b) of the sheet.
39. Normal friction situation
In the normal case of friction situation in plane strain, the average pressure p can be calculated as.
Where Q = μLp/h
h = the mean thickness between entry and exit from the rolls.
We have,
40. Therefore the rolling load P increases with the roll radius √R, depending on the
contribution from the friction hill.
• The rolling load also increases as the sheet entering the rolls becomes thinner (due
to the term eQ).
• At one point, no further reduction in thickness can be achieved if the deformation
resistance of the sheet is greater than the roll pressure. The rolls in contact with the
sheet are both severely elastically deformed.
• Small-diameter rolls which are properly stiffened against deflection by backup rolls
can produce a greater reduction before roll flattening become significant and no
further reduction of the sheet is possible.
Example: The rolling of aluminium cooking foil.
Roll diameter < 10 mm with as many as 18
backing rolls.
42. The torque in rolling can be estimated by assuming that the roll force is
centered on the work as it passes between the rolls, and that it acts with a
moment arm of one-half the contact length L. Thus, torque for each roll is
T=0.5FL
The power required per roll can be estimated by assuming that (F) acts in the
middle of the arc of contact; thus, in Fig. (5-4), a = L/2. Therefore, the total
power (for two rolls), in S.I. units, is
Power (in kW)
Where F is in newtons , L is in meters, and N is the revolutions per minute of the roll.
In traditional English units, the total power can be expressed as
Torque, and Power requirements
43. Defects
Roll Bending
Because of the forces acting on them, rolls undergo changes in
shape during rolling. Just as a straight beam deflects under a
transverse load, roll forces tend to bend the rolls elastically during
rolling.
44. Insufficient camber
Possible effects of insufficient camber (a) : edge wrinkling (b), warping (c), centerline cracking (d), and (e) residual stresses.
45. Over camber
Effects of over-cambering(a): residual stresses(b), edge cracking (c), centerline splitting (d), and (e). wavy center
47. Edge cracking
Steels used for machining automotive or precision machinery
parts contain non-metallic inclusions like MnS or metallic
inclusions such as Pb,Bi,Sn etc.
Homogeneous distribution of such inclusions throughout the
metal surface is required to ensure excellent machinability.
But sometimes non-uniform distribution of such inclusions result
in the formation of brittle interfaces in the matrix which act as
crack initiation sites.
Because of the existence of these brittle interfaces steels
subjected to rolling hardly have sufficient deformability.
As a result, cracking occurs along the edges during hot rolling of
free machining steel billets and wire rods.
48. Centre line cracking
Centre-line cracking due to rolling process leads to the formation of
centre splits whose mechanism of formation is similar to that of
edge cracks.
These defects are caused due to non-homogeneous plastic
deformation across the width.
Due to rolling pressure, the lateral spread is more towards the
edges than the centre.
Due to such non homogeneous deformation, the edges experience
tension and the central portions experience compressive stresses.
Such distribution of stresses lead to a split along the central portion
in severe cases.
49. Alligatoring
Alligatoring will occur when lateral spread is greater
in the centre than the surface (surface in tension,
centre in compression) and with the presence of
metallurgical weakness along the centerline.
This type of fracture is accentuated if there is any
curling of the sheet because one roll is higher or
lower than the centerline of the roll gap.
50. Advancements in Rolling mechanism
Direct linking of cold strip rolling process
Development of endless hot strip rolling
Crown and shape control rolling
Intelligent rolling
Numerical simulation of Rolling process
Reheating furnace technology
Scale control
Rolling lubrication
Cooling of rolled steel
Hard Plate Rolling (HPR) process
Differential Speed Rolling (DSR) process
51. Hard Plate Rolling (HPR) process
AZ91 Mg Alloy
As cast condition: T.S: 250MPa el.: 5-10%
Conventional process: T.S: <~350 MPa el.:<~15%
HPR process: T.S: 371MPa el.:23%
The Mg-9Al-1Zn (AZ91) plates processed by HPR consist of coarse grains of 30–60 μm, exhibiting a typical basal
texture, fine grains of 1–5 μm and ultrafine (sub) grains of 200–500 nm, both of the latter two having a weakened
texture.
The superior properties should be mainly attributed to the cooperation effect of the multimodal grain structure and
weakened texture, where the former facilitates a strong work hardening while the latter promotes the basal slip.
52. Differential Speed Rolling (DSR) process
Hydrostatic SPD methods such as cyclic extrusion compression (CEC), equal-channel angular pressing (ECAP), and
high-pressure torsion (HPT).
In SPD processes, the material is subjected to a very large plastic deformation (true strain ε is even greater than 80)
usually being conducted under a hydrostatic pressure and room temperature conditions.
These SPD methods also exhibit some serious disadvantages, e.g., a poor process efficiency, small dimensions of
produced (semi-) products, or a necessity of using specialized machines and tools.
53. a) Normal rolling b) DDR c)DFR d) DSR
A differential speed rolling (DSR) is a modification of the rolling
process which involves a deformation with different values of a
rotational speed of the upper and the lower rolls. This kind of
processing belongs to the group of asymmetric rolling processes
that have been already introduced to a large-scale production of flat
steel products.
DSR (cont.)
The main characteristic of the DSR method is a value of a rolls
speed differentiation coefficient R defined as a ratio of the
upper to lower rolls speed.
54. Roumina and Sinclair reported that the differentiation of rolls speed
results with a shifting of so-called neutral points (the position where
the sheet velocity equals the roll velocity) on upper and lower
surfaces of the sample.
The neutral point associated with the slow roll is shifted toward the
entrance of the roll gap, while the neutral point associated with the
fast roll is moved toward the exit of the roll gap.
DSR (cont.)
55. Kim et al. reported that in oxygen-free copper, submicron grain size of 820 nm is obtained after the 65 % thickness
reduction in a single rolling pass by the DSR method (the R = 3). This processing also leads to a formation of a large
fraction of high-angle grain boundaries (HAGBs) (~60 %) and maintaining a high electrical conductivity (that proves a low
level of structure defects).
56. Jiang et al. [22] on pure aluminum subjected to the DSR process. The authors found that the cold rolling (with the R = 3)
of commercially pure aluminum to 90 % of thickness reduction leads to a formation of microstructure composed of
submicron-equiaxed grains and a high fraction of HAGBs (~50 %).