When we start the mold design, we should pay more attention to consider several schemes, measure the advantages and disadvantages of each scheme, and choose one of them. For T mold, we should also take it seriously. Due to the reason of time cognition, the design that was considered reasonable at that time must be improved after production and use practice.
After handing over the design scheme, we should communicate with the factory to understand the processing process and the situation in manufacturing and use. Each mold should have a fixed analysis experience, summed up the process of gain and loss, in order to continuously improve the level of mold design.
The design should refer to similar drawings designed in the past and learn from their experience and lessons.
The mold design department should be a whole, not each design member for their own, especially in the mold design conclusions, must have a unique style.
The main basis is the product drawing and sample provided to us by the customer. Designers must carefully analyze and digest the products and samples, and check all items one by one during the design process.
>Plastic products with high appearance requirements and low dimensional accuracy requirements, such as toys, etc., in addition to the specific size, the other sizes as long as they fit well.
>Products with strict requirements for appearance and size.
Whether the demoulding slope is reasonable.
Product wall thickness and uniformity.
Types of plastics. (Selection of die steel and determination of shrinkage rate)
Surface requirements.
Product color.
In general, color has no direct influence on mold design. When the product wall is thick, the appearance is large, easy to produce uneven color; And the darker the color, the more obvious the product defects are exposed.
If there are surface electroplated products, and a mold with multiple cavities, it is necessary to consider the installation of auxiliary runner to connect the products together, until the completion of the plating process will be separated.
Product batch is an important basis for mold design, customers must provide a range to determine the number of mold cavities, size, mold material selection and life.
Designers must carefully consider and check to meet the requirements.
1) Analyze and digest the products and samples.
2) We should know whether the customer has requirements on the injection machine specifications to determine the size range of the mold.
3) Determine the number and placement of cavity.
4) Determination of parting surface.
5) If there is a row, rhombic structure should be understood first.
6) Gating system design
7) Determination of Mosaic structure.
8) Ejection and reset system design.
9) Cooling and heating system design.
10) Guiding and positioning device.
11) Determine the mold and select standard parts.
12) Mold steel selection.
13) Complete the structure drawing, mold drawing and material opening.
14) Finally print out the drawing, check it, and submit it to the mold design team leader and supervisor.
Although it is in the selection of molding materials, molding equipment, in the expected process conditions for mold design, but people's understanding is often not perfect, so must be in the mold processing after the completion of the trial test, to see how the quality of the molding parts. Always find after, to eliminate the error of repair mold.
There are more types of adverse phenomena in plastic parts, and the reasons are also very complex. There are mold reasons and process conditions reasons, and the two are often intertwined. Before mold repair, it is necessary to conduct detailed analysis and research according to the actual situation of the adverse phenomenon of plastic parts, find out the causes of the defects of plastic parts and put forward remedial methods. Because the forming conditions are easy to change, so the general practice is to change the forming conditions first, when the change of forming conditions can not solve the problem, only consider repairing the mold.
Repair mold should be more careful, not very sure not to act rashly. The reason is that once the mold condition is changed, it can not be reformed and restored to the original state.
After testing, if the mold is not used for the time being, it should be completely wiped off stripping dregs, dust, oil, etc., coated with butter or other anti-rust oil or anti-rust agent, and sent to the storage place for safekeeping.
From the beginning of mold design to the success of mold processing and inspection, the technical data generated during this period, such as assignment book, parts drawing, technical specification, mold assembly drawing, mold parts drawing, base drawing, mold design specification, inspection record table, trial mold repair record, etc., shall be systematically organized, bound, numbered and filed in accordance with the provisions. It seems very troublesome to do so, but it is very useful to repair the mold and design the new mold in the future.