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GLOSSARY OF PRESS TOOL TERMS

GLOSSARY OF PRESS TOOL TERMS

ANNEALING:
A process involving the heating and cooling of a metal, commonly used to induce softening.
The term refers to treatments intended to alter mechanical or physical properties or to produce a definite microstructure.
BEAD:
A narrow ridge in a sheet-metal work piece or part, commonly formed for reinforcement draw:
(a) A bead used for controlling metal flow.
(b) Rib like projections on draw ring or hold-down surfaces for controlling metal flow.
BED, PRESS:

The stationary and usually horizontal part of a press that serves as a table to which a bolster plate or lower die assembly is mounted.

BEND ANGLE:
The angle through which a bending operation is performed.

BENDING:
The straining of material usually flat sheet or strip metal, by moving it around a straight axis which lies in the neutral plane.

BEND RADIUS:
(a) The inside radius at the bend in the work
(b) The corresponding radius on the punch or on the die.

BLANK:
A precut metal shape, ready for a subsequent press operation.

BLANK DEVELOPMENT:
(a) The technique of determining the size and shape of a blank.
(b) The resultant flat pattern.

BLANK HOLDER:
The part of a drawing or forming dies which holds the work piece against the draw ring to control metal flow.
BLANKING.
The operation of cutting or shearing a piece out of stock to a predetermined contour.


BOLSTER PLATE:
A plate secured to the press bed for locating and supporting the die assembly.

BUCKLING:
A bulge, bend, kink, or other wavy condition of the work piece caused by compressive stresses.


BULGING:
The process of expanding the walls of a cup, shell or tube with an internally expanding
segmental punch or a punch composed of air, liquids, or semi liquids, such as waxes or Rubber and other elastomers.
BURNISHING:
The process of smoothening or plastically smear¬ing a metal surface to improve its finish.
BURR SIDE:
The side of a punched blank that presents a rough edge around its periphery or around a hole or opening in it.

CAM ACTION:
A motion at an angle to the direction of an applied force, achieved by a wedge or cam.

DIE HEIGHT (SHUT HEIGHT):
The distance from the finished top face of the upper shoe to the finished bottom face of the lower shoe, immediately after the die operation and with the work in the die.

DIE HOLDER:
A plate or block upon which the die block is mounted.

DIE RADIUS:
The radius at the edge of a female die over which metal is formed or drawn into the die.

DRAWABILITY:
(a) A measure of the feasible deformation of a blank during a drawing process;
(b) Percentage of reduction in diameter of a blank when it is drawn to a shell of maximum practical depth.

DRAWING:
A process in which a punch causes flat metal to flow into a die cavity to assume the shape of a seamless hollow vessel.

EMBOSSING:
A process that produces relatively shallow indentations or raised designs with theoretically no change in metal thickness.
EXTRUSION:
The plastic flow of a metal through a die orifice.

IRONING:
An operation in which the thickness of the shell wall is reduced and its surface smoothened.

KNOCKOUT:.
A mechanism for ejecting blanks or other work from a die. Commonly located on the side, but may be located under the bolster.

NOTCHING:
The cutting out of various shapes from the edge of a strip, blank, or part.

PARTING:
An operation usually performed to produce two or more parts from one common stamping.

PIERCING:
The process of die-cutting holes in sheet or plate material. Pilot pin or projection provided for locating work in. subsequent operations from a previously punched or drilled hole.
PRESS:
A machine having a stationary bed or anvil, and a slide (ram or hammer) which has a controlled reciprocating motion toward and away from the bed surface and at right angles to it. The slide being guided in the frame of the machine to give a definite path of motion.

PUNCH:
(a) The male tool part, usually the upper member and mounted on the slide;
(b) To die-cut a hole in sheet or plate material;
(c) A general term for the press operation of producing holes of various sizes in sheets, plates, or rolled shapes.

PUNCH HOLDER:
The plate or part of the die which holds the punch.

SCRAP CUTTER:
A shear or cutter operated by the press 6r built into a die for cutting scrap into sizes for convenient removal from the die or disposal.

SHAVING:
A secondary shearing or cutting operation in which the surface of a previously cut edge is finished or smoothened.

SHEAR:
(a) A tool for cutting metal and other material by the closing motion of two sharp, closely adjoining edges;
(b) To cut by shearing dies or blades;
(c) An inclination between two cuttings.

SLITTING:
Cutting or shearing along single lines; used either to cut strips from a sheet or to cut along lines of a given length or contour in a sheet or part.

SLUG:
A small piece of material, usually scrap, produced in piercing or punching holes in sheet material.



SPOTTING:
The fitting of one part of a die to another, by applying an oil color to the surface of the finished part and bringing it against the surface of the intended mating part, the high spots being marked by the transferred color.

SPRING-BACK:
The extent to which metal tends to return to its original shape or position after undergoing a forming operation.

STAMP:
(a) The general term to denote all press working;
(b) To impress lettering or designs by pressure into the surface of a material.

STRIPPER:
A device for removing the work piece or part from the punch.

STRIPPER PLATE:
A plate (solid or movable) used to strip the work piece or part from the punch; it may also guide the stock.

STRIPPING:
The operation of removing the work piece or part from the punch.

TRIMMING:
Trimming is the term applied to the operation of cutting scrap off a partially or fully shaped part to an established trim line.

ELEMENTS OF PRESS TOOL

ELEMENTS OF PRESS TOOL

BASE PLATE

It is also called as die shoe or bolsters plate. Its main function is to provide a rigid foundation or base to the assembly. It assembles the fixed half of the tool.

Material: ms or ci.


TOP PLATE

It is the top portion of the complete tool, which holds the top assembly or complete Tool through the punch holder.

Material: ms or ci.


GUIDE PILLAR

These are cylindrical pins known as guide pins or guide pillars. These provide accurate alignment to the die set. The contacting surface of pillars and guide bushes have h7/h6 fit where as the press fitted portion of the bush with top plate have h7/j5 tolerance and are ground. One end of pillar press

fitted in the base plate with h7/p6 tolerance. The other portion, which is sufficient long, provides guide for top plate for easy sliding.

Material: Case Hardened steel. IS: 17Mn1Cr95 HRC: 56-58.

GUIDE BUSH

These are mounted on the top plates, which provide smooth sliding contact between pillars and top plates.

Material: Case Hardened Steel IS: 17Mn1Cr95 HRC: 56-58


DIE

A complete tool consisting of a pair or a combination of pairs of mating members for producing work in presses. It includes well supporting and actuating part of the tool. It is a female part of a complete die.

Material: HCHCr IS: T215Cr12 HRC: 58-60

PUNCH

It is a male member of a complete dies which mates or acts in conjunction with the female die to provide a desired effect upon the material being worked.

Material: HCHCr IS: T215Cr12 HRC: 60-62

PUNCH HOLDER

It is a plate, which holds the punch.

Material: OHNS IS: T110w2Cr1

SHANK

This is a projection from the upper shoe which enters the press slide flange recess and is clamped to the slide or press ram.

Material: MS IS: ST 42

PUNCH BACK PLATE

It is a plate that supports the punch and is situated behind the punch holder plate. It avoids the dent marks that may produce during operation to the top plate.

Material: OHNS IS: T110w2Cr1

STRIPPER PLATE

It is a plate solid or movable used to strip the work piece or part from the punch. It may or may not guide the stock.

Material: MS IS: ST 42

TYPES:

1. Fixed or close or box stripper

2. Traveling or floating stripper

STRIP GUIDE

In press tool the long pre-sheared stock strip to be fed through out the die surface. The strip guide combines the two metal strips or parallel blocks, which are screwed and doweled on the die surface in alignment with the die parameters. It acts as a gauge. It is one of the important elements of the progressive tools with fixed as well as floating stripper.

Material: Gauge Steel HRC: 48-50

SHEDDERS

It is used to expel the work piece from the die cavity. Shedder actuation may be achieved by

1. Pneumatic cylinder or cushion

2. Hydraulic cylinders or cushion

3. Rubber pads

4. Springs

Material: OHNS IS: T110w2Cr1 HRC: 58-60

PILOTS

Pilots are used to align the components accurately for secondary operation.


Press Tool



Press tool is a device by which the sheet metal can be converted into required shape by various press operations. It can also be defined as a device used for punching out sheet metal components from the stock strip by a device called press. Various cutting and non-cutting tools will be loaded between fixed table and moving ram of a press. The pressure when exerted from top and bottom sides by the press, the component is produced according to the punch and dies profiles in the tool. The component is produced from a press tool is applicable in different aspects like automobile parts.

For each automotive body panel, the sheet metal stamping process requires two distinct Types of

equipment: the stamping press and a set of stamping dies. The set of stamping dies represents custom manufacturing equipment used to make specific product geometry. The stamping press represents flexible manufacturing equipment, capable of producing many different automotive body panels (hood, door, fender, etc.) simply by changing the stamping dies. Thus, a particular stamping press produces an individual panel in batches, making the setup of the dies critical to controlling the process mean.

Sheet metal panels require multiple die operations using either a single press or a series of presses in a press line. Stamping dies and presses have numerous input variables (tonnage, shut height, press parallelism, counterbalance pressure, nitrogen pressure in dies, press speed, etc.) that can influence stamping panel quality, especially during die setup. The resultant geometry of the sheet metal panels depends, in part, on these settings. Using the same press settings each time a particular die is set would help reduce long run variation in the associated panels. Unfortunately, the relationship of the numerous press settings and other process input factors (incoming material, blank size, etc.) on panel geometry is not well documented or understood by manufacturers. For example, many of the input

variable settings use a single value for the entire panel. Individual panels, however, have multiple features in different areas that are not necessarily controlled by the same set of input variable settings. This situation limits the ability to bring the process back to the target value when SPC charts exhibit out-of-control conditions for certain features, especially if other features do not change .In addition, none of the process input variables possess a direct cause-and-effect relationship with a panel feature. For example, increasing the tonnage by some amount will not cause a predictable change in a panel feature, as it does in machining where adjusting the position of a cutting tool has a predictable impact on the process mean.

Sheet metal stampings have now replaced many components which were earlier cast or machined. Material economy & the resultant reduction in weight and cost , high productivity , use of unskilled labor , & a high degree of possible precision have rendered presswork indispensable for many mass production goods such as electronics appliances , steel furniture, utensils & automotives. The entire top of a car can be finished to size from a single sheet metal. There is no need for further machining as in the case of castings or forgings.

Metal Stamping is the process of taking blank sheet metal of various thickness and material, and forming it into different shapes by different operations.

Today’s modern technology demands technique to produce quality products at an affordable price to gain an edge over competitors .Sheet metal stamping plays a major role in fulfilling the requirements of modern technology.

The design & analysis of press tools by computer simulation will be highly beneficial to analyze process assessment capabilities & thereby saving lot of expenditures by avoiding repeated and costly tryouts.


High speed stamping & Terminal tool with multiple operation & multi stage tool with higher accuracy.

    Capabilities:
  • Blank Development
  • Drawing Tool
  • Forming Tool
  • Bending Tool
  • Progressive Tool
  • Compound Tool
  • Panel Dies

Another kind of press is a set of plates with a relief, or depth-based design, in them. The metal is placed between the plates, and the plates are pressed up against each other, deforming the metal in the desired fashion. This may be coining or embossing or forming. A punch press is used for forming holes. Capping Presses form caps from rolls of aluminium foil at up to 660 per minute.

Progressive stamping is a manufacturing method that can encompass punching, coining, bending and several ways of modifying the metal, combined with an automatic feeding system. The feeding system pushes a coil of metal through all of the stations of a progressive stamping die. Each station performs one or more operations until a finished part is made per the requirements on the print. The final operation is a cut-off operation, which separates the finished part from the carrying web. The carrying web, along with metal that is punched away in previous operations, is considered scrap metal.

STATEMENT OF THE PROBLEM

Design, Manufacture & Analysis of Press tools as a set of stage tools for Front Right/Left Disk Protector is the subject considered for this project work.

A new component is usually manufactured without giving enough attention to simulation & analysis aspects, by trial & error process in order to obtain a part without defects. Even the previous experience of designers is not enough to decrease the number of trial, rework on tool & redesign cycles.

OBJECTIVE OF THE STUDY

The prime objective of the study is to design a set of tools to produce the component that exceeds the expectations of the customer in Aspects like Quality, Cost & On time delivery, it holds out the strong probability of achieving the following:

1. A die or set of dies that combines maximum production and least maintenance with “lowest feasible cost, for the desired or expected life”.

2. Maximum utilization of the least expensive stamping material that will satisfactorily function.

3. Most efficient press working practices.

4. A stamped product that consistently meets sales and service requirements of shape, dimensions, strength, finish, style and utility.

SCOPE OF WORK

The basic concept involved in this method to attain the objective is the systematic and correct tool design, a well planned approach has been employed. The methodology consists of the following as detailed here and in the subsequent chapters.

· Component analysis.

· Step by step approach to die design.

· Selection of tooling materials.

· Tool fabrication.

· Tool assembly and tryout,

· Tool cost estimation.

DRAFTING OF ASSEMBLY.

All tool elements were done in AUTOCAD. This stage involved making the drawings of assembly, individual tool elements etc.

MAKING WIRE CUTTING 2D PROFILES

The tools had wire cut profiles in the die and shedder. Making auto cad wire cut profiles for the tools was another task.

PREPARING 3D MODELS

The punch, die and shedder of certain tools needed to be CNC machined. For this 3D models of the punch, die and shedders were made in Power Shape.