A set of reliable mold design is mainly reflected in quality of molded plastic products (appearance quality and dimensional stability), convenient, rapid, concise processing and manufacturing, which saves money and manpower, leaves room for correction and improvement, safe and stable in use, easy to maintain, has a short molding cycle and long service life during injection molding, and reasonable mold manufacturing processability.

 

Customers provide product drawings→analyze products→confirm plastic varieties→confirm mold material→transfer engineering drawings→make a mirror image by shrinking→improve assembly drawing→order mold base→order mold core material→draft→3D parting→determine runner /Gating method→Refer to layout drawing for structural design→dismantle inserts→correct 3D→engineering drawings including: (mold core/insert/mold blank/parts)→make BOM table→proof and review.

When we start mold design, we should pay more attention to considering several options, weigh advantages and disadvantages of each option, choose one of them, and take T mold seriously. Because of time understanding, it was believed that a reasonable design at that time would definitely have possible improvements through production and use practices.
After handing over design plan, it is necessary to communicate more with factory to understand processing and manufacturing conditions. Each set of molds should have a fixed analysis experience, sum up process of gains and losses, in order to continuously improve level of mold design.
When designing, refer to similar drawings designed in the past to learn from its experience and lessons.
Mold design department is supposed to be a whole, each design member cannot work independently, especially in terms of mold design summary conclusions, it must have a unique style.

Main basis is product drawings and samples provided to us by customers. Designers must carefully analyze, digest products and samples. At the same time, they must check all items one by one during design process.
Correctness of dimensional accuracy related dimensions.
(1). For clinker products with high appearance requirements and low dimensional accuracy requirements, such as toys, except for specific dimensions, the other dimensions only need to be in good agreement.
(2). Products with strict requirements for onlookers size.
Whether draft angle is reasonable.
Product wall thickness and uniformity.
Plastic types. (Plastic types want to steal choice of mold steel and determine shrinkage rate)
Surface requirements.
Product color.
In general, color has no direct influence on mold design. When product wall is thick and appearance is larger, uneven color is likely to occur; and the darker color, the more obvious product defects are exposed.
Whether there is post-treatment after product is formed.
If there are products with surface electroplating, and a mold with multiple cavities, you must consider setting up auxiliary runners to connect products together, then separate them after electroplating process is completed.
Batch of products
Batch of products is an important basis for mold design, customer must provide a range to determine number of mold cavities, size, mold material selection and life.
Injection molding machine specifications.
Other requirements of customers.
Designer must carefully consider and check to meet compatibility requirements.

 

1. Analyze, digest products and templates.
2. It should be understood whether customer has requirements for specifications of injection machine to determine size of mold.
3. Determine and rank number of cavities.
4. Parting surface is determined.
5. If there is a slider, oblique square structure should be understood first.
6. Design of gating system
7. Determination of mosaic structure.
8. Ejection. Reset system design.
9. Cooling and heating system design.
10. Guiding. Positioning device.
11. Determine mold base and select standard parts.
12. Selection of mold steel.
13. Complete structure diagram, mold base diagram, and cut material.
14. Finally, print out drawing, check it, submit it to mold design team leader and supervisor.

Although mold design is carried out under expected process conditions when molding material and molding equipment are selected, people’s understanding is often imperfect. Therefore, after mold processing is completed, mold trails must be performed to see how quality of molded part is. After finding that there is always a problem, repair model to eliminate errors.
There are many types of undesirable phenomena in plastic parts, and reasons are very complicated. There are reasons for molds and process conditions. The two are often intertwined. Before repairing mold, according to actual situation of undesirable phenomenon of plastic part, a detailed analysis and research should be carried out, remedy method should be proposed after finding cause of defect of plastic part. Because molding conditions are easy to change, general approach is to change molding conditions first, and only consider repairing mold when changing molding conditions cannot solve problem.
Repair molds should be more cautious, do not act rashly if you are not sure. Reason is that once mold conditions are changed, major modifications and restorations cannot be made.

After test, if mold is not used temporarily, it should completely wipe off mold release residue, dust, oil, etc., apply butter or other anti-rust oil or anti-rust agent, and keep it in storage place.
From beginning of design of mold until mold is successfully processed and passed inspection, technical data generated during this period, such as task book, part drawing, technical specification, mold assembly drawing, mold part drawing, base drawing, mold design manual, inspection records, trial and repair records, etc., are systematically sorted, bound, numbered and archived according to regulations. This seems very troublesome, but it is very useful for repairing mold in the future and designing a new mold.