Formwork composition and specifications

1. Template composition
Stamping die composition will be based on the type of mold and the composition and the difference, there are smooth configuration type structure and reverse configuration type structure two categories. The former is the most commonly used structure, the latter structure is mainly used in the extension molding die or with special mold.
The main work includes:
(1). Digital drafting - three-dimensional product and mold models into two-dimensional engineering drawings used in conventional processing;
(2)．Digital design of the mold - according to the product model and design intent, the establishment of the relevant mold three-dimensional solid model;
(3)．Digital analysis and simulation of the mold - according to the product forming process conditions, structural analysis of mold parts, thermal analysis, fatigue analysis and motion analysis of the mold;
(4)．Simulation of product forming process - injection molding, press molding;
(5)．Customize the mold design standard parts and standard design process suitable for the company;
(6)．Mold production management.
2. Mold specifications
(1). Mold size and locking screws
The mold plate size should be larger than the working area and the standard mold plate size should be selected. The template locking screw position configuration is related to the type of mold and template size. Among the single engineering mold most commonly used locking screws configured in the four corners, the most standard form of work area can be widely used. Long molds and continuous molds most often use locking screws configured in the four corners and the middle position.
(2). Thickness of mold plate
The selection of the thickness of the mold plate is absolutely related to the structure of the mold, the type of stamping process, the processing force of the stamping process, and the precision of the stamping process, etc. It is difficult to determine the thickness of the mold based on theoretical calculation. Based on theoretical calculations to determine the thickness of the mold is difficult, generally by experience, the design of the template thickness should be used as little as possible, with the height of the mold and clamping height to standardize in order to facilitate the procurement and inventory management.
IV. Template design
Continuous mold main template has a punch fixed plate, pressure plate, mother template, etc., its structure design according to the precision of stamping products, the number of production, mold processing equipment and processing methods, mold maintenance methods, there are the following three forms: (1) the whole piece, (2) yoke type, (3) inserted type.
1. Whole block type
The whole block type formwork is also known as one construction type, its processing shape must be closed. Block type template is mainly used for simple structure or high precision molds, its processing mode to cutting-based (no heat treatment), using heat treatment template must be implemented again wire cutting or electrical discharge machining and grinding process. Template size long (continuous mold) occasions will use two or more pieces of one body type and use.
2. Yoke type
The center part of the yoke type formwork is machined into a concave groove for assembling block products. Its structure according to the application requirements, concave groove part can be other template composition. The advantages of this yoke type formwork structure are: the groove part is easy to process, the width of the groove part can be adjusted, and the processing accuracy is good. But low rigidity is its disadvantage.
Yoke type formwork design considerations are as follows:
(1). Yoke plate structure and block parts embedded with the middle fit or light fit, such as the use of strong pressure fit will make the yoke plate change.
(2). The yoke plate has the function of holding the block part, and must have sufficient rigidity to withstand the side pressure and surface pressure of the block part. And in order to make the yoke plate groove part and block part get close combination, its groove part corner made into the escape gap processing, such as the yoke plate groove part corner can not be made into the escape gap processing, then the block part must be made into the escape gap processing.
(3). The internal shape of the block part shall be considered at the same time, and the reference plane shall be clarified. In order to avoid deformation during stamping, the shape of each block part shall be taken into consideration.
(4). When the yoke is assembled with many pieces of block parts, the accumulated processing error of each block part causes the pitch to change, and the solution is to design the middle block part in an adjustable way.
(5). When the block parts are assembled in a side-by-side mold structure, the block parts will be subjected to side pressure during the punching process, resulting in gaps between the block parts or tilting of the block parts. This phenomenon is an important cause of stamping defects such as dimensional defects and chip blockage, so adequate countermeasures must be taken.
(6). There are five fixing methods for the block parts in the yoke plate according to their size and shape as follows: A. Fixed by locking screws, B. Fixed by keys, C. Fixed by key, D. Fixed by shoulder, E. Fixed by pressing on the upper pressing parts (such as guide plate).
3. Insertion type
Round or square concave part is processed in the template, and the block-shaped parts are embedded in the template, which is called inserted structure, and this structure has less cumulative machining tolerance, high rigidity, and good reproducibility of accuracy when disassembling and assembling. Due to the advantages of easy machining, machining accuracy determined by the working machine, and fewer final adjustment works, the inserted template structure has become the mainstream of precision stamping molds, but its disadvantage is the need for high-precision hole processing machines.
When this template structure is adopted for continuous stamping dies, in order to make the template have high rigidity requirement, it is designed with empty station. The precautions for the inserted template construction are as follows:
(1). Embedded hole processing: the template embedded hole processing using vertical milling machine (or jig milling machine), integrated processing machine, jig boring machine, jig grinder, wire-cutting discharge processing machine. Embedded in the hole processing standard, the use of wire cutting and electrical discharge machining machine, in order to improve its processing accuracy is to carry out two or more wire cutting processing.
(2). Insert fixing method: The determining factors for the insert fixing method are the accuracy of processing, the ease of assembly and disassembly, and the possibility of adjustment. There are four fixing methods for embedded parts as follows: A. Fixing with screws, B. Fixing with shoulders, C. Fixing with toe blocks, and D. Pressing with plates on the upper part of the embedded parts. The female template insert fixing method is also used to press into the fit, at this time should be avoided due to the processing of thermal expansion and the result of relaxation, the use of circular mold set inserts for processing irregular holes should be designed to prevent the method of slewing.
(3). Insert assembly and disassembly considerations: Inserts and their holes require high machining accuracy to be assembled. In order to get even a slight dimensional error can be adjusted in the assembly, it is advisable to consider the countermeasures in advance, embedded parts processing specific considerations are the following five items: A. With a press into the introduction part, B. To adjust the embedded parts to the state of press into the correct position, C. Embedded parts are equipped with holes on the bottom surface of the press with the hole, D. Screws should be used in the same size of the screw locking, in order to facilitate the locking and unlocking, E. In order to prevent the assembly of the orientation should be designed to prevent errors. E. In order to prevent the grouping of cubic direction error, should be designed to prevent dull chamfer processing.