Course Design - Die Tooling Design

Contents

INTRODUCTION

1 ANALYSIS OF INITIAL DATA

1.1Select Production Type

1.2 Analysis of Technical Requirements

1.3 Analysis of part material properties

1.4 Processability Analysis

2 OPTION SELECTION AND DEFINITION

PROCESS STRUCTURES

2.1 Development of routing and operating technologies

2.2 Selection of the process diagram of the stamp

3 SELECTION OF OPTIMAL CUTTING OPTION

3.1 Define the shape and dimensions of the workpiece

3.2 Material opening

4 PROCESS CALCULATIONS

5 CALCULATION OF PUNCH DESIGN PARAMETERS

5.1 Calculation of actuating dimensions of working parts of dies

5.2 Determination of die pressure center

5.3 Selection of materials for production of die parts

6 PRESS SELECTION

7 VERIFICATION CALCULATIONS

7.1 Punch Strength Calculation

7.2 Matrix Strength Calculation

8 TECHNICAL STANDARDISATION OF STAMPING OPERATION

9 DETERMINATION OF DIE RESISTANCE

10 LUBRICATION SELECTION

11 ARRANGEMENT AND OPERATION OF DIE

LIST OF SOURCES USED

APPLICATIONS

Introduction

The work considers the process of punching holes in a piece blank made of sheet material, calculation of the force and operation of punching is carried out, as well as the executive dimensions of the die and punch are determined. The main parts of the die were substantiated in the work by selecting the most rational process diagram of the die.

Typical mechanization means are provided which can be used in the manufacture of a given part.

The purpose of the work is to study the main methods of cold sheet stamping, determine the main structural and technological parameters of the stamp and press, take into account the main features of various types of stamping.

Select Production Type

The type of production is tentatively determined based on the annual program and the size of the part (initial project data) according to existing recommendations [10]: the nature of production is serial, especially small parts (up to 90 mm), the number of parts over 10 to 100 thousand pcs/year.

In mass production, cold stamping is characterized by the use of both universal, cheap and special using new technological methods (rubber stamping, hydraulic stamping, blast stamping, combined and sequential stamping).

Technical Requirements Analysis

The "sector" part is characterized by the accuracy of the outer contour according to the 13th quota. Two holes are made in the part along the 13th quota as well. The accuracy of the angular dimension also when recalculating to linear dimensions and inter-axial distances also correspond to the 13th quota. Surface roughness as per Ra = 6.3mkm. quality and accuracy of surfaces correspond to economically feasible [3 C.314320; 5 Page 4446].

This part is characterized by a set of main design bases: installation (PxVxVu), double support (PxPu (VxVu)), support ((PxPu) (VxVu) [Bz]).

Part thickness s = 1.5 mm by normal degree of accuracy of cold rolled stock St3sp.

Analyzing Part Material Properties

The part material shall meet the requirements of GOST 38094 (Table 1.1).

The mechanical properties of the material include the temporary tensile and compression resistance [theta], yield strength [theta], hardness HB, elongation [theta], etc.

The physical properties include density p, Young's modulus E, melting and crystallization temperature T, heat capacity C, electrical resistance α, etc.

The chemical properties of the material are primarily determined by its chemical composition, as well as corrosion resistance.

The processing properties of the material include cutting and pressure workability, weldability, hardenability, etc.

The mechanical characteristics also include the so-called conditional technological value - resistance to the slice αsr.

Development of routing and operating technologies

Based on the engineering specification and the equipment used in serial production, we will prepare a preliminary processing route for the part "sector" and summarize it in table 2.1.

It is possible to use more advanced methods using combined dies and double-acting presses, as well as combining cutting with punching and editing. Considering that combined dies are more expensive than simple dies and require more expensive presses than simple presses, let us dwell on the use of simple operations and cheap equipment.

According to [3 Page 299, Page 312] it is determinable the key indicators defining the choice of type of stamps: at seriality 50000sht/year application of replaceable package stamps of simple type of average group of cost or special stamps of high group of cost is possible. The most optimal is the use of simple type dies.

Arrangement and operation of the stamp

The die consists of a standard block according to GOST 1312683 with cast iron plates and two posts of steel 20. The racks are installed in the upper plate using guide bushings for sliding catch as per GOST 1312083. posts are installed in the lower plate by interference fit. A punch backing plate is bolted to the upper plate, in which two standard punches are installed as per GOST 1662180. A matrix backing plate is bolted to the bottom plate, in which two standard matrices according to GOST 1663780 are installed. A stencil in the form of an elbow and a retainer in the form of a bolt and a plate with a spring for basing and fixing the part are attached to the die plate. On separate stepped bolts according to GOST 1878680, a spring extractor is installed in the form of an intermediate plate on two springs. A shank with a flange as per GOST 1671871 is installed on the upper plate for attachment to the press slider. The die itself is attached to the press table using elbows installed in T-shaped slots of the table.

The stamp works on the next cycle. As the press slider moves, holes in the part are punched. At the same time, waste falls into through holes in the press plate and through holes in the table falls into a special container. Simultaneously with the upper plate, an intermediate plate moves. At the return course of the punches, the upper plate grips with itself a part that, when colliding with the intermediate plate, is removed from the punches and falls on the lower plate. After that, the press is automatically disconnected and the worker puts the part in a special container. At the same time, it is necessary not to forget about the need to lubricate the parts and working units of the die.