Sheet metal working involves cutting and forming thin metal sheets. The main processes are cutting, bending, and drawing. Cutting separates sheets into parts using dies and presses. Proper die clearance is important for good cuts. Forces to cut metal depend on material thickness, diameter/length of cut, and material strength. Progressive and compound dies can perform multiple operations in one or a few presses. The center of pressure allows even force distribution for irregular cuts to avoid bending. Tapered or stepped punches can reduce high cutting forces. Efficient strip layout minimizes scrap.
Ch6 sheetmetw proc (1) Erdi Karaçal Mechanical Engineer University of GaziantepErdi Karaçal
The document discusses sheet metal working processes and cutting operations. It describes the three major categories of sheet metal processes as cutting, bending, and drawing. Cutting operations like shearing, blanking, and piercing are used to separate sheet metal into pieces or make holes. Proper die clearances and cutting forces must be considered for optimal cutting. Tools called punches and dies are used to perform these operations on stamping presses.
Ch6 sheetmetw proc Erdi Karaçal Mechanical Engineer University of GaziantepErdi Karaçal
The document discusses sheet metal working processes and focuses on cutting operations like blanking and punching. It describes how sheet metal is cut using punch and die tools on presses. The cutting involves shearing the metal between sharp edges of the punch and die. Process parameters like clearance between the tools and stock thickness determine the cutting forces and quality of cut edges. Techniques like stepped punches and tapered edges can reduce high cutting forces. The document also covers determining the center of pressure for irregular shapes and optimizing scrap strip layout for blanking operations.
The document discusses various sheet metal processes including shearing, punching, blanking, bending, drawing, spinning, and forming. It provides details on each process such as the basic setup, how it works, applications, advantages, and equations to calculate forces required. Key points covered include how shearing produces rough cut edges, the importance of proper clearance in punching, the stages of deep drawing including thinning, and how spinning can form axisymmetric shapes through localized deformation.
This document provides an overview of sheet metal forming processes. It discusses shearing processes like punching and blanking. It describes the effects of clearance between the punch and die on shearing. It also covers other processes like bending, bead forming, flanging, roll forming, and stretch forming. Various press types and die configurations used in sheet metal forming are also summarized.
Sheet metal working involves cutting, bending, and drawing operations on thin metal sheets. There are three major categories of sheet metal processes: cutting uses shearing actions to cut sheet metal, bending strains sheet metal around a straight axis, and drawing forms sheet metal into convex or concave shapes. Common sheet metal parts are used in automobiles, appliances, furniture and other industrial and consumer products.
This document provides an overview of sheet metal forming processes. It discusses various sheet metal operations including cutting (shearing) operations like punching, blanking, and trimming as well as forming operations like bending, drawing, and squeezing. Bending operations including V-bending and edge bending are described. Drawing operations for forming hollow shapes are also covered along with squeezing processes like embossing and coining.
Metal sheet forming, its types & operationsUmair Raza
The document discusses various methods of sheet metal forming processes. It introduces stretching, shearing, blanking, bending, deep drawing, and redrawing. It then discusses variables in sheet forming processes and defects that can occur. The document provides classifications of sheet metal parts and describes various forming equipment and machines used. It also details different types of sheet metal forming processes like curling, bending, ironing, laser cutting, hydroforming, punching, progressive forming, rubber hydroforming, spinning, explosive forming, and stretching and deep drawing.
The document discusses sheet metalworking processes. It defines sheet metalworking as cutting and forming operations on thin metal sheets between 0.4-6mm thick. Common operations include cutting (shearing, blanking, punching), bending, drawing and other specialized processes. Key factors in determining the feasibility and setup of operations like clearance, bend allowance, and tests for drawing are also covered. Dies, presses and press components used to perform sheet metalworking are described.
Ch6 sheetmetw proc (1) Erdi Karaçal Mechanical Engineer University of GaziantepErdi Karaçal
The document discusses sheet metal working processes and cutting operations. It describes the three major categories of sheet metal processes as cutting, bending, and drawing. Cutting operations like shearing, blanking, and piercing are used to separate sheet metal into pieces or make holes. Proper die clearances and cutting forces must be considered for optimal cutting. Tools called punches and dies are used to perform these operations on stamping presses.
Ch6 sheetmetw proc Erdi Karaçal Mechanical Engineer University of GaziantepErdi Karaçal
The document discusses sheet metal working processes and focuses on cutting operations like blanking and punching. It describes how sheet metal is cut using punch and die tools on presses. The cutting involves shearing the metal between sharp edges of the punch and die. Process parameters like clearance between the tools and stock thickness determine the cutting forces and quality of cut edges. Techniques like stepped punches and tapered edges can reduce high cutting forces. The document also covers determining the center of pressure for irregular shapes and optimizing scrap strip layout for blanking operations.
The document discusses various sheet metal processes including shearing, punching, blanking, bending, drawing, spinning, and forming. It provides details on each process such as the basic setup, how it works, applications, advantages, and equations to calculate forces required. Key points covered include how shearing produces rough cut edges, the importance of proper clearance in punching, the stages of deep drawing including thinning, and how spinning can form axisymmetric shapes through localized deformation.
This document provides an overview of sheet metal forming processes. It discusses shearing processes like punching and blanking. It describes the effects of clearance between the punch and die on shearing. It also covers other processes like bending, bead forming, flanging, roll forming, and stretch forming. Various press types and die configurations used in sheet metal forming are also summarized.
Sheet metal working involves cutting, bending, and drawing operations on thin metal sheets. There are three major categories of sheet metal processes: cutting uses shearing actions to cut sheet metal, bending strains sheet metal around a straight axis, and drawing forms sheet metal into convex or concave shapes. Common sheet metal parts are used in automobiles, appliances, furniture and other industrial and consumer products.
This document provides an overview of sheet metal forming processes. It discusses various sheet metal operations including cutting (shearing) operations like punching, blanking, and trimming as well as forming operations like bending, drawing, and squeezing. Bending operations including V-bending and edge bending are described. Drawing operations for forming hollow shapes are also covered along with squeezing processes like embossing and coining.
Metal sheet forming, its types & operationsUmair Raza
The document discusses various methods of sheet metal forming processes. It introduces stretching, shearing, blanking, bending, deep drawing, and redrawing. It then discusses variables in sheet forming processes and defects that can occur. The document provides classifications of sheet metal parts and describes various forming equipment and machines used. It also details different types of sheet metal forming processes like curling, bending, ironing, laser cutting, hydroforming, punching, progressive forming, rubber hydroforming, spinning, explosive forming, and stretching and deep drawing.
The document discusses sheet metalworking processes. It defines sheet metalworking as cutting and forming operations on thin metal sheets between 0.4-6mm thick. Common operations include cutting (shearing, blanking, punching), bending, drawing and other specialized processes. Key factors in determining the feasibility and setup of operations like clearance, bend allowance, and tests for drawing are also covered. Dies, presses and press components used to perform sheet metalworking are described.
Sheet Metal Working, Temperature and sheet metal forming, Applications Sheet Metal Parts, Categories of sheet metal processes, Shearing, stages in shearing action, Punch and Die Sizes, Sheet Metal Bending
Wear Analysis of Tool in Milling YTL7D SteelIJRES Journal
In the process of milling die steel YTL7D, the properties of high hardness and high wear resistance of
the workpiece material led to that the tool Subjected to severe wear, and the life of the tool is lower. In this
research, the wear law of rake face and flank face of the ball end mill was discussed. And the tool wear
mechanism in the process of milling YTL7D steel is revealed in this paper, to provide a theoretical guidance for
the development of rational process and follow-up studies.
This document discusses various sheet metal forming processes and operations. It describes how sheet metal is produced by rolling metal into thin sheets less than 6 mm thick. Common applications of sheet metal include aircraft bodies, automobile bodies, and household utensils. The document outlines various cutting, bending, drawing, and forming operations used to shape sheet metal, including shearing, punching, bending, deep drawing, spinning, and roll forming. It also discusses defects in forming processes and components of dies used in sheet metalworking.
This document provides an overview of sheet metal forming processes. It begins by describing common applications of sheet metal forming such as metal desks, appliances, and car bodies. It then discusses various sheet metal forming operations like punching, blanking, bending, and deep drawing. The document discusses important sheet metal characteristics like formability, anisotropy, and springback that influence formability. It also summarizes various techniques for cutting, bending, and shaping sheet metal, as well as methods for minimizing scrap.
Sheet metal can be formed into thin, flat pieces and cut and bent into various shapes. It is one of the fundamental materials used in metalworking. Sheet metal operations include shearing, punching, blanking, notching, and forming processes like bending, spinning, and embossing. Shearing involves cutting through the material between a punch and die, while punching and blanking remove a portion of material. Sheet metal has many applications and can be made from metals like steel, aluminum, and copper.
This document provides information on various sheet metal operations used in metal fabrication. It begins with an introduction to pressed metal frames and the advantages of sheet metal. Various sheet metal cutting and forming operations are described such as punching, blanking, deep drawing, bending, squeezing, and notchting. Hooke's law and its application to sheet metal forming is explained. Details are provided on punching, blanking, deep drawing, and bending operations including the forces involved. Applications of sheet metal operations in various industries are mentioned. Finally, types of sheet metals and mechanical linkages used in sheet metal presses are discussed.
The document discusses a study to reduce variation in the outer diameter of driven plates produced at an automotive clutch manufacturing company. The objectives are to reduce scrap, increase quality, and reduce costs. The driven plates are made through operations like blanking and piercing. Variation occurs after these operations, affecting the outer diameter dimension. The document reviews factors that can influence variation in blanking processes, like punch and die clearance, geometry, and material properties. It aims to analyze how these parameters impact the outer diameter variation after blanking and piercing of the driven plates.
This document provides an overview of sheet metal forming processes. It discusses that sheet metal forming is used to produce parts with versatile shapes and is lightweight. Common materials used are low-carbon steel, aluminum, and titanium. The main forming processes discussed are shearing, punching, bending, deep drawing, and stamping. It covers the characteristics of sheet metal that influence formability like elongation, anisotropy, and springback. Forming parameters that affect processes like deep drawing are also summarized such as blankholder pressure, draw ratio, and clearance.
This document discusses various sheet metal forming processes. It describes cutting processes like shearing, blanking, and punching. It also describes bending, drawing, embossing, stretch forming, roll forming, and spinning. Sheet metal is commonly used to make parts for vehicles, appliances, furniture and more. Cutting is done using punches and dies in presses or shears. Proper clearance and tool sizes are important. Bending involves straining metal around an axis. Drawing forms complex curved shapes using punches and dies.
This document discusses sheet metal working processes. It begins by explaining that sheet metal forming dates back thousands of years and is used to make a wide variety of consumer and industrial products. The main sheet metal forming processes are stretching, bending, deep drawing, and press working. Press working shapes sheet metal using dies and punches without removing material. The document then goes into details about various sheet metal forming operations, tools, and calculations for processes like bending, deep drawing, blanking, and punching.
Metal Forming, Production Engineering IIዘረአዳም ዘመንቆረር
The document discusses sheet metal forming and cutting operations. It covers topics like sheet metal forming processes, applications of sheet metal, and basic sheet metal cutting operations like shearing, blanking, and punching. The engineering analysis of sheet metal cutting operations focuses on clearance between the punch and die, cutting forces, and determining punch and die sizes. Forming operations like bending, drawing, and associated engineering analysis are also covered.
Study of split punch and die of the sheet metal blanking process for length c...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Extrusion, Drawing, Forging and Sheetmetal working processesmulualemamar
This Material presents about metal forming processes from those it slides about bulk deformation and sheet metal working processes includes (extrusion, drawing, forging and sheet metal operations).
This document discusses forging and forging processes. It defines forging as the controlled plastic deformation of metals at elevated temperatures using compressive forces. Forging enhances mechanical properties like strength and toughness. Forgeability is the tolerance of a metal to deform without failure, and can be evaluated using hot twist, upset, and hot impact tests. Common forging materials include aluminium alloys, steels, and titanium alloys. Forging is classified as open die or close die, with close die allowing more complex shapes. Processes include drop forging, press forging, and machine forging. Forging improves properties like strength and reduces machining time.
Ch5 metalworkproc Erdi Karaçal Mechanical Engineer University of GaziantepErdi Karaçal
This document summarizes key concepts about metal working processes from Chapter 5. It discusses various metal forming techniques including forging, rolling, extrusion, and sheet metalworking. Forging processes are described in more detail, including open-die forging where the metal flows unrestrained between two flat dies, and closed-die forging where matching die blocks are used to form parts to close tolerances. The effects of temperature, friction, and material properties on metal forming are also summarized.
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.
Manufacturing Processes(Sheet Metal Forming.ppt)sadanand50
This document discusses various sheet metal forming processes including shearing, bending, deep drawing, and spinning. It provides examples of common sheet metal parts and describes key operations like punching, blanking, and fine blanking. Important considerations for sheet metal formability are outlined, such as material properties and tests. The document also covers design factors for efficient sheet metal forming and examples of equipment used.
Sheet metal operations involve cutting, forming, and finishing processes to manufacture components from thin metal plates less than 5mm thick. Cutting processes like shearing, punching, and blanking apply forces to separate material, while forming processes like drawing, spinning, bending, and embossing shape the metal without cracking. Common sheet metals include steel, aluminum, and titanium used in automotive and aircraft bodies, appliances, and more. Key forming operations are stretching, spinning, bending, and embossing which deform the metal over dies into desired contours.
This document summarizes various sheet metal forming processes and provides details on bending mechanics. It includes a table comparing characteristics of different forming processes like roll forming, stretch forming, and stamping. The document then discusses bending terminology and minimum bend radii for different materials. It also covers bending mechanics topics such as the effects of inclusions and edge conditions on cracking. Springback is analyzed through definitions of terms and models for estimating springback factor. Methods to reduce springback through techniques like overbending are presented.
The document provides a table listing various commands and shortcuts for SolidWorks. It includes categories for File, Edit, View, Insert, Tools, Window, Help and Others. For each category it lists the relevant commands and associated keyboard shortcuts. The table contains over 60 commands and shortcuts for navigating, creating, editing and viewing models in SolidWorks.
This presentation introduces a new Engineering Change Request (ECR) process alongside the existing Process Change Request (PCR) process for HYG suppliers to manage design and process changes. The ECR process is similar to the PCR but directs engineering changes to HYG's engineering team for review, while the PCR is for process changes. Suppliers submit change requests through a common front page on the HYG change request site to select the appropriate process. The presentation provides overviews and requirements for submitting ECR and PCR requests through the online system, including required fields and the review and approval process handled by HYG.
Sheet Metal Working, Temperature and sheet metal forming, Applications Sheet Metal Parts, Categories of sheet metal processes, Shearing, stages in shearing action, Punch and Die Sizes, Sheet Metal Bending
Wear Analysis of Tool in Milling YTL7D SteelIJRES Journal
In the process of milling die steel YTL7D, the properties of high hardness and high wear resistance of
the workpiece material led to that the tool Subjected to severe wear, and the life of the tool is lower. In this
research, the wear law of rake face and flank face of the ball end mill was discussed. And the tool wear
mechanism in the process of milling YTL7D steel is revealed in this paper, to provide a theoretical guidance for
the development of rational process and follow-up studies.
This document discusses various sheet metal forming processes and operations. It describes how sheet metal is produced by rolling metal into thin sheets less than 6 mm thick. Common applications of sheet metal include aircraft bodies, automobile bodies, and household utensils. The document outlines various cutting, bending, drawing, and forming operations used to shape sheet metal, including shearing, punching, bending, deep drawing, spinning, and roll forming. It also discusses defects in forming processes and components of dies used in sheet metalworking.
This document provides an overview of sheet metal forming processes. It begins by describing common applications of sheet metal forming such as metal desks, appliances, and car bodies. It then discusses various sheet metal forming operations like punching, blanking, bending, and deep drawing. The document discusses important sheet metal characteristics like formability, anisotropy, and springback that influence formability. It also summarizes various techniques for cutting, bending, and shaping sheet metal, as well as methods for minimizing scrap.
Sheet metal can be formed into thin, flat pieces and cut and bent into various shapes. It is one of the fundamental materials used in metalworking. Sheet metal operations include shearing, punching, blanking, notching, and forming processes like bending, spinning, and embossing. Shearing involves cutting through the material between a punch and die, while punching and blanking remove a portion of material. Sheet metal has many applications and can be made from metals like steel, aluminum, and copper.
This document provides information on various sheet metal operations used in metal fabrication. It begins with an introduction to pressed metal frames and the advantages of sheet metal. Various sheet metal cutting and forming operations are described such as punching, blanking, deep drawing, bending, squeezing, and notchting. Hooke's law and its application to sheet metal forming is explained. Details are provided on punching, blanking, deep drawing, and bending operations including the forces involved. Applications of sheet metal operations in various industries are mentioned. Finally, types of sheet metals and mechanical linkages used in sheet metal presses are discussed.
The document discusses a study to reduce variation in the outer diameter of driven plates produced at an automotive clutch manufacturing company. The objectives are to reduce scrap, increase quality, and reduce costs. The driven plates are made through operations like blanking and piercing. Variation occurs after these operations, affecting the outer diameter dimension. The document reviews factors that can influence variation in blanking processes, like punch and die clearance, geometry, and material properties. It aims to analyze how these parameters impact the outer diameter variation after blanking and piercing of the driven plates.
This document provides an overview of sheet metal forming processes. It discusses that sheet metal forming is used to produce parts with versatile shapes and is lightweight. Common materials used are low-carbon steel, aluminum, and titanium. The main forming processes discussed are shearing, punching, bending, deep drawing, and stamping. It covers the characteristics of sheet metal that influence formability like elongation, anisotropy, and springback. Forming parameters that affect processes like deep drawing are also summarized such as blankholder pressure, draw ratio, and clearance.
This document discusses various sheet metal forming processes. It describes cutting processes like shearing, blanking, and punching. It also describes bending, drawing, embossing, stretch forming, roll forming, and spinning. Sheet metal is commonly used to make parts for vehicles, appliances, furniture and more. Cutting is done using punches and dies in presses or shears. Proper clearance and tool sizes are important. Bending involves straining metal around an axis. Drawing forms complex curved shapes using punches and dies.
This document discusses sheet metal working processes. It begins by explaining that sheet metal forming dates back thousands of years and is used to make a wide variety of consumer and industrial products. The main sheet metal forming processes are stretching, bending, deep drawing, and press working. Press working shapes sheet metal using dies and punches without removing material. The document then goes into details about various sheet metal forming operations, tools, and calculations for processes like bending, deep drawing, blanking, and punching.
Metal Forming, Production Engineering IIዘረአዳም ዘመንቆረር
The document discusses sheet metal forming and cutting operations. It covers topics like sheet metal forming processes, applications of sheet metal, and basic sheet metal cutting operations like shearing, blanking, and punching. The engineering analysis of sheet metal cutting operations focuses on clearance between the punch and die, cutting forces, and determining punch and die sizes. Forming operations like bending, drawing, and associated engineering analysis are also covered.
Study of split punch and die of the sheet metal blanking process for length c...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Extrusion, Drawing, Forging and Sheetmetal working processesmulualemamar
This Material presents about metal forming processes from those it slides about bulk deformation and sheet metal working processes includes (extrusion, drawing, forging and sheet metal operations).
This document discusses forging and forging processes. It defines forging as the controlled plastic deformation of metals at elevated temperatures using compressive forces. Forging enhances mechanical properties like strength and toughness. Forgeability is the tolerance of a metal to deform without failure, and can be evaluated using hot twist, upset, and hot impact tests. Common forging materials include aluminium alloys, steels, and titanium alloys. Forging is classified as open die or close die, with close die allowing more complex shapes. Processes include drop forging, press forging, and machine forging. Forging improves properties like strength and reduces machining time.
Ch5 metalworkproc Erdi Karaçal Mechanical Engineer University of GaziantepErdi Karaçal
This document summarizes key concepts about metal working processes from Chapter 5. It discusses various metal forming techniques including forging, rolling, extrusion, and sheet metalworking. Forging processes are described in more detail, including open-die forging where the metal flows unrestrained between two flat dies, and closed-die forging where matching die blocks are used to form parts to close tolerances. The effects of temperature, friction, and material properties on metal forming are also summarized.
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.
Manufacturing Processes(Sheet Metal Forming.ppt)sadanand50
This document discusses various sheet metal forming processes including shearing, bending, deep drawing, and spinning. It provides examples of common sheet metal parts and describes key operations like punching, blanking, and fine blanking. Important considerations for sheet metal formability are outlined, such as material properties and tests. The document also covers design factors for efficient sheet metal forming and examples of equipment used.
Sheet metal operations involve cutting, forming, and finishing processes to manufacture components from thin metal plates less than 5mm thick. Cutting processes like shearing, punching, and blanking apply forces to separate material, while forming processes like drawing, spinning, bending, and embossing shape the metal without cracking. Common sheet metals include steel, aluminum, and titanium used in automotive and aircraft bodies, appliances, and more. Key forming operations are stretching, spinning, bending, and embossing which deform the metal over dies into desired contours.
This document summarizes various sheet metal forming processes and provides details on bending mechanics. It includes a table comparing characteristics of different forming processes like roll forming, stretch forming, and stamping. The document then discusses bending terminology and minimum bend radii for different materials. It also covers bending mechanics topics such as the effects of inclusions and edge conditions on cracking. Springback is analyzed through definitions of terms and models for estimating springback factor. Methods to reduce springback through techniques like overbending are presented.
The document provides a table listing various commands and shortcuts for SolidWorks. It includes categories for File, Edit, View, Insert, Tools, Window, Help and Others. For each category it lists the relevant commands and associated keyboard shortcuts. The table contains over 60 commands and shortcuts for navigating, creating, editing and viewing models in SolidWorks.
This presentation introduces a new Engineering Change Request (ECR) process alongside the existing Process Change Request (PCR) process for HYG suppliers to manage design and process changes. The ECR process is similar to the PCR but directs engineering changes to HYG's engineering team for review, while the PCR is for process changes. Suppliers submit change requests through a common front page on the HYG change request site to select the appropriate process. The presentation provides overviews and requirements for submitting ECR and PCR requests through the online system, including required fields and the review and approval process handled by HYG.
This presentation introduces a new Engineering Change Request (ECR) process alongside the existing Process Change Request (PCR) process for HYG suppliers to manage design and process changes. The ECR process is similar to the PCR but directs engineering changes to HYG's engineering team for review, while the PCR is for process changes. Suppliers submit change requests through a common front page on the HYG change request site to select the appropriate process. The presentation provides overviews and requirements for submitting ECR and PCR requests through the online system, including required fields and the review and approval process handled by HYG.
Change management involves planning, organizing, coordinating, and controlling changes to ensure they are implemented smoothly with minimal disruption. It is the responsibility of top management to oversee changes that affect suppliers, customers, and competitors. An effective change management process includes pre-implementation planning, implementation, and post-implementation review. It also requires testing changes and obtaining user acceptance before full production rollout. Regular audits help ensure compliance with change control procedures and guidelines.
This document discusses change management in engineering and construction projects. It defines change as any deviation from the agreed upon project scope, schedule, or cost. The importance of change management is discussed, as modern projects face challenges like reduced timelines that require changes. An effective change management process addresses changes to scope, schedule, cost and their interdependencies. The document outlines responsibilities for managing change, including for the project manager, project engineering manager, change coordinator and other roles. It describes methods for controlling changes through document review, tracking design growth, and change review meetings. The conclusion emphasizes meeting project objectives, addressing stakeholder interests, and maintaining trust and a documented process.
Change management involves planning, organizing, coordinating, and controlling changes to ensure they are implemented as approved with minimal disruption. It is the responsibility of top management to manage not only employees but also suppliers, customers, and competitors affected by changes. The steps for change management include pre-implementation, implementation, and post-implementation phases. An audit of change controls evaluates the identification, testing, approval, and documentation of all changes to ensure standards and procedures are followed.
Change management involves planning, organizing, coordinating, and controlling changes to ensure they are implemented smoothly with minimal disruption. It is the responsibility of top management to oversee changes that affect suppliers, customers, and competitors. An effective change management process includes pre-implementation planning, implementation, and post-implementation review. It also requires testing changes and obtaining user acceptance before full production rollout. Regular audits help ensure compliance with change control procedures and guidelines.
1. The document discusses different types of molds used in injection molding, including two plate molds, three plate molds, multi-daylight molds, stack molds, runnerless molds, insulated hot runner molds, and split molds.
2. It provides details on the construction and functioning of each mold type, specifically how they are designed to handle components with features like undercuts, multiple cavities, and integrated runners and sprues.
3. The advantages and disadvantages of each mold configuration are outlined, such as their effectiveness for different production needs, material savings, and ease of manufacturing.
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1. CHAPTER 6
SHEET METAL WORKING PROCESSES
6.1 INTRODUCTION
ME 333 PRODUCTION PROCESSES II
2.11.2014 CHAPTER 6 SHEET METAL
WORKING PROCESSES
1
Sheet metalworking includes cutting and forming operations performed on
relatively thin sheets of metal (0.4-6 mm).
The tooling used to perform sheet metalwork is called punch and die. Most sheet
metal operations are performed on machine tools called presses.
The term stamping press is used to distinguish these presses from forging and
extrusion presses. The sheet metal products are called stampings.
The commercial importance of sheet metalworking is significant.
The number of consumer and industrial products that include sheet metal parts:
automobile and truck bodies, airplanes, railway cars and locomotives, farm
and construction equipment, small and large appliances, office furniture,
computers and office equipment, and more. Sheet metal parts are generally
characterized by high strength, good dimensional tolerances, good surface finish,
and relatively low cost.
2. ME 333 PRODUCTION PROCESSES II
Sheet-metal processing is usually performed at room temperatures (cold working).
The exemptions are when the stock is thick, the metal is brittle, or the deformation
is significant.
These are usually cases of warm working rather than hot working.
2.11.2014 CHAPTER 6 SHEET METAL
WORKING PROCESSES
2
3. ME 333 PRODUCTION PROCESSES II
The three major categories of sheet-metal processes:
(1) cutting (shearing, blanking, piercing)
(2) bending
(3) drawing.
Cutting is used to separate large sheets into smaller pieces, to cut out a part
perimeter, or to make holes in a part.
Bending and drawing are used to form sheet metal parts into their required
shapes.
Piercing and Blanking Cut off Lancing
blank
blanking
scrap
piercing
scrap
Final shape required
Fig.6.1 Some cutting operations
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4. ME 333 PRODUCTION PROCESSES II
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Classification of Sheet
Metalworking Processes
Fig.6.2 Basic sheet
metalworking
operations:
(a) bending,
(b) drawing, and
(c) shearing;
(1) as punch first
contacts sheet and
(2) after cutting.
Force and relative
motion are indicated
by F and v
5. ME 333 PRODUCTION PROCESSES II
Classification of Sheet Metalworking Processes
Fig.6.2 Basic processes involved in forming sheet metal components. (a) Processes involving
local deformation.
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6. ME 333 PRODUCTION PROCESSES II
6.2. PIERCING AND BLANKING
A commonly used piercing-blanking die set and related terms are shown in the
following figure.
Fig.6.3 Components of a punch and die
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7. ME 333 PRODUCTION PROCESSES II
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Blanking and punching
Blanking and punching are similar sheet metal cutting operations that involve
cutting the sheet metal along a closed outline.
If the part that is cut out is the desired product, the operation is called blanking and
the product is called blank.
If the remaining stock is the desired part, the operation is called punching. Both
operations are illustrated on the example of producing a washer:
Starting stock produced
by shearing operation
from a big metal sheet
Fig.6.4 Steps
in production
of washer
8. ME 333 PRODUCTION PROCESSES II
The cutting of metal between die components is a shearing process in which the
metal is stressed in shear between two cutting edges to the point of fracture, or
beyond its ultimate strength.
The metal is subjected to both tensile and compressive stresses; stretching beyond
the elastic limit occurs; then plastic deformation, reduction in area, and, finally,
fracturing starts and becomes complete.
Fig.6.5 Shearing of sheet metal
between punch and die
Blanking punch diameter= Db-2c
Blanking die diameter= Db
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Hole punch diameter= Dh
Hole die diameter= Dh+2c
9. ME 333 PRODUCTION PROCESSES II
The cutting of metal between die components is a shearing process in which the
metal is stressed in shear between two cutting edges to the point of fracture, or
beyond its ultimate strength. The metal is subjected to both tensile and
compressive stresses; stretching beyond the elastic limit occurs; then plastic
deformation, reduction in area, and, finally, fracturing starts and becomes complete.
Fig.6.5 Shearing of sheet metal between punch and die
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10. ME 333 PRODUCTION PROCESSES II
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Engineering analysis of metal cutting:
Cutting of sheet metal is accomplished by a shearing action between two sharp edges. The
shearing action is illustrated in the figure:
Fig. 6.6. Shearing of sheet metal
between two cutting edges:
(1) just before the punch contacts
work;
(2) punch begins to push into
work, causing plastic
deformation;
(3) punch compresses and
penetrates into work, causing a
smooth cut surface; and
(4) fracture is initiated at the
opposing cutting edges that
separate the sheet.
Symbols v and F indicate motion
and applied force, respectively.
Fig.6.3 Shearing
11. ME 333 PRODUCTION PROCESSES II
At the top of the cut surface is a region
called the rollover. This corresponds to
the depression made by the punch in the
work prior to cutting. It is where initial
plastic deformation occured in the work.
Just below the rollover is a relatively small
region called the burnish. This results
from penetration of the punch into the
work before fracture began.
Beneath the burnish is the fractured
zone, a relatively rough surface of the cut
edge where continued downward
movement of the punch caused fracture of
the metal.
Finally, at the bottom of the edge is a
burr, a sharp corner on the edge caused
by elongation of the metal during final
seperation of the two pieces.
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12. 2.11.2014 CHAPTER 6 SHEET METAL
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Process parameters in sheet metal cutting are clearence between punch and die,
stock thickness, type of metal and its strength and length of the cut
Clearance c in a shearing operation is the space between the mating members of
a die set (e.g.punch and die).
For optimum finish of cut edge, proper clearance is necessary and is a function
of the kind, thickness, and hardness of the work material.
In an ideal cutting operation the punch penetrates the material to a depth equal to
about 1/3 of its thickness before fracture occurs, and forces an equal portion of
the material into the die opening.
Common die clearances (linear clearance) are 2-5% of the material thickness.
Angular clearance is gradient given to the hole in the die such that cut material will
easily be removed. Angular clearance is usually ground from 0.25⁰ to 1.5⁰ per side.
ME 333 PRODUCTION PROCESSES II
6.2.1. Engineering Analysis_CLEARANCE
13. ME 333 PRODUCTION PROCESSES II
The correct clearance depends on sheet-metal type and thickness t:
c = a*t
where a is the allowance (a = 0.075 for steels and 0.060 for aluminum alloys).
If the clearance is not set correctly, either an excessive force or an oversized burr
can occur:
Fig.6.7 Effect of clearance:
(Left) clearance too small
optimal
causes
fracture
less than
and excessive
forces, and (Right) clearance
too large causes oversized
burr.
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14. ME 333 PRODUCTION PROCESSES II
Figure (a) Effect of the clearance, c, between punch and die on the
deformation zone in shearing.
As the clearance increases, the material tends to be pulled into the die rather
than be sheared. In practice, clearances usually range between 2% and 10%
of the thickness of the sheet. (b) Microhardness (HV) contours for a 6.4-mm
(0.25-in) thick AISI 1020 hot-rolled steel in the sheared region.
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15. ME 333 PRODUCTION PROCESSES II
The calculated clearance value must be;
- substracted from the die punch diameter for blanking operations or
- added to die hole diameter for punching:
Fig.6.8
Die diameter is enlarged with clearance c in punching.
In blanking, the punch diameter is decreased to account for clearance.
D is the nominal size of the final product.
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16. ME 333 PRODUCTION PROCESSES II
An angular clearance must be provided for the die hole to allow parts to drop
through it:
Fig.6.9 Angular clearance
for the die opening in
punching and blanking.
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17. 2.11.2014 CHAPTER 6 SHEET METAL
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6.2.2. CUTTING FORCE
ME 333 PRODUCTION PROCESSES II
The pressure (or stress) required to cut (shear) work material is;
P D tS
P S L t
where;
S= shear strength of material, kg/mm2
D= hole diameter, mm
L= shear length, mm
t= material thickness, mm
For example to produce a hole of 20mmX20mm in a material 2mm in
thickness with 40 kg/mm2 shear strength:
P= 40 kg/mm2x(2x20+2x20)mmx2mm
P= 40x160 kg= 6400 kg force is required.
(for round holes)
(for any contours)
18. 6.2.3 TOOLS AND DIES FOR CUTTING OPERATIONS
ME 333 PRODUCTION PROCESSES II
When the die is designed to perform a single operation (for example, cutting,
blanking, or punching) with each stroke of the press, it is referred to as a simple
die:
Fig.6.10 The basic components of the simple blanking and punching dies
Simple dies
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19. ME 333 PRODUCTION PROCESSES II
More complicated pressworking dies include:
• compound die to perform two or more operations at a single position of the
metal strip
• progressive die to perform two or more operations at two or more positions of
the metal strip
Fig.6.11 Method of making a simple washer in a compound blanking and punching die
Multi-operational dies
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20. ME 333 PRODUCTION PROCESSES II
Multi-operational dies
Schematic illustrations: (a) before and (b) after
blanking a common washer in a compound die.
Note the separate movements of the die (for
blanking) and the punch (for punching the hole in
the washer). (c) Schematic illustration of making a
washer in a progressive die. (d) Forming of the top
piece of an aerosol spray can in a progressive die.
Note that the part is attached to the strip until the
last operation is completed.
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21. 6.2.4 CENTRE OF PRESSURE
ME 333 PRODUCTION PROCESSES II
Sheet metal part that to be blanked is of irregular shape the summation of
shearing forces on one side of the center of the ram may greatly exceed the
forces on the other side. This result in bending and undesirable deflections might
happen. Center of pressure is a point, which the summation of shearing forces
will be symmetrical. This point is the center of gravity of the line that is the
perimeter of the blank. It is not the center of gravity of the area.
y
2r
x y
2r
rSin
α 3
x
a b
3
y
h
Fig.6.14 Center of pressure for some shapes
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22. Procedure to find center of pressure:
1. Divide cutting edges into line elements, 1,2,3, ...
2. Find the lengths l1, l2, l3, ...
3. Find the center of gravity of each element as x1, x2, x3, ..., y1, y2, y3, ...
4. Calculate the center of pressure from:
ME 333 PRODUCTION PROCESSES II
l1 l2 l3 .... l
x
l1x1 l2x2 l3x3 ....
lx
l1 l2 l3 .... l
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y
l1 y1 l2 y2 l3 y3 ....
ly
23. ME 333 PRODUCTION PROCESSES II
EXAMPLE
Find the center of pressure and the required cutting force of the following blank
(S=40 kg/mm2 and t=2mm).
2
3
1
4
5
6
Element l X Y (l)(x) (l)(y)
1 4.00 0.00 6.25 0.00 25.00
2 4.71 1.50 9.20 7.05 43.33
3 3.20 4.00 7.00 12.80 22.40
4 2.50 4.00 5.00 10.00 12.50
5 3.00 1.50 4.25 4.50 12.75
6 1.57 1.00 0.00 1.57 0.00
TOTAL 18.98 35.92 115.98
x
35.92
1.89cm
18.98 18.98
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y
115.98
6.10cm
and the cutting force is;
P= LtS 189.8mmx2mmx40kg/mm2 =15184 kg
24. Since cutting operations are characterized by very high forces exerted over very
short periods of time, it is some times desirable to reduce the force and spread it
over a longer portion of the ram stroke.
Two methods are frequently used to reduce cutting forces and to smooth out the
heavy loads.
1. Step the punch lengths; the load may thus be reduced approx. 50%.
2. Tapering the punch; grind the face of the punch or die at a small shear angle
with the horizontal. This has the effect of reducing the area in shear at any time,
and may reduce cutting force as much as 50%. The angle chosen should
provide a change in punch length of about 1.5 times of material thickness. It is
usually preferable to a double cut to prevent setup of lateral force components.
ME 333 PRODUCTION PROCESSES II
6.2.5 REDUCING CUTTING FORCES
0.25+t
Fig.6.15 Different configurations
for reducing the cutting force
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25. ME 333 PRODUCTION PROCESSES II
Fig.6.– Effect of different clearances when punching hard and soft alloys
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26. In designing parts to be blanked from strip material, economical strip utilization is of
high importance. The goal should be at least 75% utilization.
ME 333 PRODUCTION PROCESSES II
6.3 SCRAP-STRIP LAYOUT FOR BLANKING
where;
t : thickness of the stock,
W: width of the stock,
B: space between part and edge (1.5t),
C: lead of the die (L+B),
L&H: dimensions of the work piece.
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27. ME 333 PRODUCTION PROCESSES II
Locating the work piece for maximum economy is very important.
Total
%Scrap
Scrap
X100
Total
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%Util.
Util.
X100
28. ME 333 PRODUCTION PROCESSES II
If two strips (250 mm and 125 mm width) are available for the production of 100
mm blanks, which one have to be preferred for maximum material utilization?
HOMEWORK:
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29. Bending is defined as the straining of the sheet metal around a straight edge:
ME 333 PRODUCTION PROCESSES II
6.4 BENDING
Fig.6.15 Bending of sheet metal
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30. ME 333 PRODUCTION PROCESSES II
Bending operations involve the processes of V-bending and edge bending:
Fig.6.16 (Left) V-bending, and (Right) edge bending; (1) before and (2) after bending
•V-bending—sheet metal is bent along a straight line between a V-shape punch and die.
•Edge bending—bending of the cantilever part of the sheet around the die edge.
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31. Bending is the process by which a straight length is transformed into a curved
length. It is a very common forming process for changing sheet and plate into
channel, tanks, etc.
For a given bending operation the bend radius can not be made smaller than a
certain value, otherwise the metal will crack on the outer tensile surface. Minimum
bend radius is usually expressed in multiples of the sheets thickness. It varies
considerable between different metal and always increases with cold working. Bend
radius is not less than 1 mm and for high strength sheet alloys the minimum bend
radius may be 5t or higher.
ME 333 PRODUCTION PROCESSES II
R - bend radius
BA - bend allowance
- bend angle
L0 - original length
t - sheet thickness
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Lf L0
Lf=L1+L2+BA Rmin>5t practical
32. This is the stretching length that occurs
during bending. It must be accounted to
determine the length of the blank,
ME 333 PRODUCTION PROCESSES II
Kba = 0.33
Kba = 0.50
for R < 2t
for R ≥ 2t
where Lb is the length of the blank, L are
the lengths of the straight parts of the
blank, BA is the bend allowance,
Fig.6.17 Calculation of bend allowance
where A is the bend angle; t is the sheet thickness;
R is the bend radius; Kba is a factor to estimate stretching,
defined as follows:
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33. ME 333 PRODUCTION PROCESSES II
The minimum bend radius for a given thickness of sheet can be predicted fairly
accurately from the reduction of area measured in tension test, Ar.
1
1
t 2Ar
Rmin
r r
R
2A A 2
(1 A )2
min
r
t
for Ar< 0.2,
r
for A > 0.2, Ao
Ao Af
Ar
Another common problem is springback. It is the dimensional change of the formed
part after pressure of the forming tool has been removed. It results from the change
in strain produced by elastic recovery.
o Rf t/2
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Ro t/2
Springback ratio
f
34. ME 333 PRODUCTION PROCESSES II
The commonest method of compensating for springback is to bend the part to a
smaller radius of curvature than is desired so that after springback the part has
the proper radius.
Springback is the elastic recovery leading to the increase of the included angle
when the bending pressure is removed.
To compensate for springback two methods are commonly used:
1. Overbending—the punch angle and radius are smaller than the final ones.
2. Bottoming—squeezing the part at the end of the stroke.
Fig.6.18 Springback in bending
Fig.6.19 Compensation of springback by:
(a) and (b) overbending; (c) and (d) bottoming
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35. ME 333 PRODUCTION PROCESSES II
The force required bending a length L about a radius R may be estimated from;
Lt2
2(R t/2) 2
P o
tan
Bending forces
The maximum bending force is estimated as
where Kbf is the constant that depends on the process, Kbf = 1.33 for V-bending
and Kbf = 0.33 for edge bending; w is the width of bending; D is the die opening
dimension as shown in the figure:
Fig.6.20 Die opening dimension D,
(a) V-bending, (b) edge bending
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36. ME 333 PRODUCTION PROCESSES II
Equipment for bending operations
Fig.6.21 Press brake with CNC gauging system Fig.6.22 Dies and stages in the press brake
forming of a roll bead
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37. Deep drawing is the metal working
process used for shaping flat sheets
into cup-shaped articles such as
bathtubs, shell cases, and
automobile fenders. Generally a hold
down or pressure pad is required to
press the blank against the die to
prevent wrinkling. Optional pressure
pad from the bottom may also be
used.
ME 333 PRODUCTION PROCESSES II
6.5 DEEP DRAWING (Derin Çekme)
Fig.6.23 Drawing of a cup shaped part
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38. Deep drawing of a cup-shaped part
ME 333 PRODUCTION PROCESSES II
Fig.6.24 Deep drawing of a cup-shaped part: (Left) start of the
operation before punch contacts blank, and (Right) end of stroke
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39. ME 333 PRODUCTION PROCESSES II
In the deep drawing of a cup the metal
is subjected to three different types of
deformations. In the flange part, as it is
drawn in, the outer circumference must
continuously decrease from that of the
original blank Do to that of the finish
cup Dp. This means that it is
subjected to a compressive strain in the
hoop (tangential) direction and a tensile
strain in the radial direction. As a result
of these principal strains, there is a
continual increase in the thickness as
the metal moves inward. However, as
the metal pass over the die radius, it is
first bend and then straightened while
at the same time being subjected to a
tensile stress. This plastic bending
under tension results in considerable
thinning. Punch region is under very
little stress.
Fig.6.23 Types of deformations in different region
during deep drawing of a cup shaped part
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40. Clearance
Clearance c is the distance between the punch and die and is about 10% greater
than the stock thickness:
c = 1.1t
Holding force
The improper application of the holding force can cause severe defects in the
drawn parts such as (a) flange wrinkling or (b) wall wrinkling if the holding force is
too small, and (c) tearing if the folding force is overestimated.
ME 333 PRODUCTION PROCESSES II
Fig.6.25 Defects in deep drawing of a cup-shaped part
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41. 2.11.2014 CHAPTER 6 SHEET METAL
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ME 333 PRODUCTION PROCESSES II
The force on the punch required to produce a cup is the summation of the ideal
force of deformation, the frictional forces, and the force required to produce
ironing. Mathematical calculation of the drawing force is very complex. Following
approximate equation is developed:
o
D d
d
P dt 1.1 𝑙n
D
e B
2H /2
where;
P = total punch load,
d = punch diameter,
H = hold drawn force,
t = wall thickness,
= efficiency
o= average flow stress,
D = blank diameter,
B = force required to bend,
= coefficient of friction,
Drawing force may be calculated for practical purposes by:
P odt when LDR 2 (Limiting Drawing Ratio)
42. ME 333 PRODUCTION PROCESSES II
The drawability of a metal is measured by the ratio of the blank diameter to the
diameter of the cup drawn from the blank (usually accepted as punch diameter). For
a given material there is a Limiting Drawing Ratio (LDR), representing the largest
blank that can be drawn through a die without tearing.
d
LDR D e
Where, is an efficiency term to account for frictional losses. If =1, then LDR=2.7
while =0.7, LDR2 which is used in most practical applications.
Some of the practical considerations which affect drawability:
Rd 10t
Rp should be big enough to prevent tearing.
Clearance between punch and die; 20 to 40% greater than “t”.
Hold-down pressure; 2% of o and lubricate die walls
The diameter of blank required to draw a given cup may be obtained approximately
by equating surface areas.
where; h is height of cup.
D 2
d 2
dh
4 4
and D d 2
4dh
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43. ME 333 PRODUCTION PROCESSES II
If the shape change required by the part design is too severe (limiting drawing ratio is
too high, or LDR is not sufficient to form a desired cup), complete forming of the part
require more than one drawing step. The second drawing step and any further
drawing steps if needed, are referred to as redrawing. Throat angle is 10-15.
Redrawing is generally done in decreasing ratios as given below:
(D/d)= 1.43, 1.33, 1.25, 1.19, 1.14 and 1.11.
If these redrawing steps are not enough to reach required cup diameter, annealing
have to be performed and then redrawing can be performed.
last draw
1st draw
6.5.1 REDRAWING
Fig.6.26 Redrawing of a cup
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44. ME 333 PRODUCTION PROCESSES II
A 200 mm blank is to be drawn to a 50 mm cup. Estimate the minimum number of
draws required using the drawing ratios given below:
6.5.2 EXAMPLE:
56.38>50
Draw 1st 2nd 3rd 4th 5th 6th
Ratio 1.43 1.33 1.25 1.19 1.14 1.10
Solution:
LDR=2 D/d = 200/50 = 4 > 2
So that redrawing is necessary.
1.
1.43
1
1
D
D
1.43 D
200
139.86
2.
1.33
2
1.33 D
139.86
105.16
2
D1
D
3.
1.25
3
1.25 D
105.16
84.13
3
D2
D
4. 70.69
1.19
84.13
3
1.19 D4
D4
D
5.
1.14
5
1.14 D
70.69
62.01
5
D4
D
6. 56.38
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44
1.1
62.01
5
1.1 D6
D6
D
45. ME 333 PRODUCTION PROCESSES II
Therefore annealing should be applied. But it might be better to anneal the blank
before 6th draw to reduce number of redraws. We know that LDR=2. So that if
annealing is performed after 3rd draw where D3 = 84.13 mm, than ratio to reach
required cup diameter is:
50
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45
84.13
1.68 < 2
Therefore, after 3rd draw, blank is annealed and then redraw with a ratio of 1.68 to
obtain required cup diameter. The required number of drawing is then 4.
46. The Guerin process involves the use of a thick rubber pad to form sheet metal
over a positive form block:
ME 333 PRODUCTION PROCESSES II
6.6 OTHER SHEET-METAL FORMING OPERATIONS
Fig.6.27 The Guerin process: (Left) start of the operation before
rubber pad contacts sheet, and (Right) end of stroke
The Guerin process
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47. Examples of equipment and products manufactured by the Guerin process:
ME 333 PRODUCTION PROCESSES II
Fig.6.28 Rubber pad press showing
forming tools on the press table
Advantages:
Limitations:
Area of application:
Fig.6.29 A large number of different components
can be made simultaneously during one press cycle
with rubber pad presses
small cost of tooling
for relatively shallow shapes
small-quantity production
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48. It is similar to Guerin process but instead of rubber pad a rubber diaphragm
filled with fluid is used:
Fig.6.30 Hydroform process:
(1) start-up, no fluid in the cavity;
(2)press closed, cavity pressurized
with hydraulic fluid;
(3)punch pressed into work to form
part.
Symbols:
v - velocity,
F – applied force, and
p - hydraulic pressure
ME 333 PRODUCTION PROCESSES II
Hydroforming
Advantages:
Limitations:
Area of application:
small cost of tooling
simple shapes
small-quantity production
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49. In stretch forming the sheet metal is stretched and bent to achieve the desired shape:
ME 333 PRODUCTION PROCESSES II
Fig.6.31 Stretch forming: (1) start of the process; (2) form die is pressed into the work
causing it to stretched and bent over the form. Symbols: v - velocity, Fdie - applied force
Stretch forming
Advantages:
Limitations:
Area of application:
small cost of tooling, large parts
simple shapes
small-quantity production
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50. Spinning is a metal forming process in which an axially symmetric part is gradually
shaped over a mandrel by means of a rounded tool or roller:
ME 333 PRODUCTION PROCESSES II
Fig.6.32 In spinning operation, flat circular blanks are often formed into hollow shapes such
as photographic reflectors. In a lathe, tool is forced against a rotating disk, gradually forcing
the metal over the chuck to conform to its shape. Chucks and follow blocks are usually
made of wood for this operation
Spinning
Advantages:
Limitations:
Area of application:
small cost of tooling, large parts (up to 5 m or more)
only axially symmetric parts
small-quantity production
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51. These are metal forming processes in which large amount of energy is applied in a
very short time. Some of the most important HREF operations include:
ME 333 PRODUCTION PROCESSES II
Fig.6.33 Explosive forming: (1) set-up, (2) explosive is detonated, and (3) shock wave
forms part
HIGH-ENERGY-RATE FORMING (HERF)
It involves the use of an explosive charge placed in water to form sheet into the die cavity.
Explosive forming
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52. ME 333 PRODUCTION PROCESSES II
Fig.6.34 Explosively formed elliptical
dome 3-m in diameter being
removed from the forming die
Advantages:
Limitations:
Area of application:
small cost of tooling, large parts
skilled and experienced labor
large parts typical of the aerospace industry
Explosively formed elliptical dome 3-m in diameter being removed from
the forming die
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53. This is a HREF process in which a shock wave to deform the work into a die cavity is
generated by the discharge of electrical energy between two electrodes submerged
in water. Similar to explosive forming, but applied only to small part sizes.
ME 333 PRODUCTION PROCESSES II
Fig.6.35 Setup of electrohydraulic forming
Electrohydraulic forming
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54. The sheet metal is deformed by the mechanical force of an electromagnetic field
induced in the workpiece by a coil:
ME 333 PRODUCTION PROCESSES II
Fig.6.36 Electromagnetic
forming: (1) set-up in which
coil is inserted into tubular
workpiece surrounded by
die, (2) formed part
Electromagnetic forming
Advantages:
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can produce shapes, which cannot be
produced easily by the other processes
suitable for magnetic materials
most widely used HERF process to
form tubular parts
Limitations:
Area of application:
55. ME 333 PRODUCTION PROCESSES II
If two strips (250 mm and 125 mm width) are available for the production of 100
mm blanks, which one have to be preferred for maximum material utilization?
HOMEWORK:
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56. 2.11.2014 CHAPTER 6 SHEET METAL
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THE END
ME 333 PRODUCTION PROCESSES II
57. ME 333 PRODUCTION PROCESSES II
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