Press Tool Design

The press tool ( commonly known as die/ dies) is an assembly of die, punch, punch plate, punch backplate, stripper plate, etc. to produce sheet metal components/ stamped parts from the flat metal sheet.

In this Article You will learn

1.Press Working Terminology

2.Metal stamping Press Tools Components 2.1 Structural Components

2.2 Working Components

2.3 Guiding or Locating Components

2.4 Stripping Components

2.5 Fastening Components

2.6 Feeding Components

3.The Requirement of Press Tool Design

4.Design of Press Tools

5.What is Strip Layout?

6.Theory of Press Tool Stamping Process

7.Forces Disposition

7.1 Vertical Force

7.2 Horizontal Force

8.What is Press Tool Clearance?

9.Importance of Proper press tool Clearance

9.1 Die clearance for punching press tool 9.2 Die Clearance for Blanking press tool

10.Bending Press Tools Principles

10.1 Bend Radius

10.2 Bend Allowance

10.3 Blank Size or Developed length

11.Computer-aided designing of press tools

Press Working Terminology

Before designing the sheet metal stamping process Press tool, it is necessary to understand the configuration and components of the press tool. The press tool consists of Punch/ Punches, Die, Punch Plate, Backup plate, Stripper, ejectors many more components. To better understand the main components of the press and dies, just have a look at the given figure.

Ram ( Slide): Moving Component of the press which transfers the mechanical or hydraulic force from the Flywheel /hydraulic system to the Press tool for sheet metal stamping.

Punch Holder ( Upper Shoe): This is the upper part of the die set which contains guidepost pushing. The whole upper section (generally contains Punch, punch plate) of the die set is mounted on the upper shoe.

Die Holder ( Lower Shoe ): This is the lower part of the die set which contains guidepost. The whole lower section ( Generally contain die, stripper) of the die set is mounted on the upper shoe.

Back up Plate: Backup plate is placed so that the intensity of pressure does not become excessive on the punch holder. It is also called Punch backplate and Pressure Plate.

Bolster Plate: This is a thick plate secured to the bed which is used for supporting & locating the die set. Die: Die is a female part of the die block/press tool for producing the given job work in a press. Die and punch work together to make the desired shape product. Stripper: A stripper is used to strip the metal strip from a punch or die. Guidepost & Guide post bushing: This two-component of the press tool guide the die set to maintain the alignment during the operation. Properly lubricated, and positioned, they improve tool operation and contribute to producing quality products. This is also called a pillar die set.

Bolster Plate: This is a thick plate secured to the bed which is used for supporting & locating the die set.

Die: Die is a female part of the die block/press tool for producing the given job work in a press. Die and punch work together to make the desired shape product.

Stripper: A stripper is used to strip the metal strip from a punch or die.

Guidepost & Guide post bushing: This two-component of the press tool guide the die set to maintain the alignment during the operation. Properly lubricated, and positioned, they improve tool operation and contribute to producing quality products. This is also called a pillar die set. Shut Height: The distance between the top of the bed and bottom of the slide, with its stroke down and adjustment up.

Press tool design should suit the type of production i.e mass production, small-batch, or Huge batch. Press tools should meet the following requirements: The press tools should ensure the demanded output, safe operation & easy maintenance. Press tools should be designed in such a way that possible standard components are used for the manufacturing of products. Press tools should be designed for maximum utilization of material as well as manpower. Working Parts of the press tools must be strong and durable and replaceable when worn out. Dimensional accuracy and surface finish must be within tolerances.

Design of Press Tools

The sheet metal stamping process is a very fast and precise manufacturing process. But what if, press tool is not working efficiently or it takes many more operations to produce stamped parts. So it is very important to design an economy friendly and time-saving press tools. Steps to design any Sheet metal stamping press tool or die. The computing of the required force ( Press tonnage) Selection of press Determination of shut height of the tool computing die thickness and margins ( Minimum cross-section) Drawing strip layout and comparing material utilization Design of locating elements Selection of Hardware Drawing die plan ( Pillar sets, Punch height, and mounting) Identify the center of pressure and checking scrap disposal Drawing Details.