injection mold key point
（1）. The rubber inlet shall be set at the thick part of the product to ensure smooth and complete mold filling;（2）. Try to set it at the place that does not affect the appearance and function of the product, but at the edge or bottom;
（3）. In the cold material cavity near the gate, the pull rod is often set at the end to facilitate the demoulding of the gate;
（4）. For large or flat products, it is recommended to use multi-point pouring to prevent product warpage, deformation and material shortage;
（5）.The position should be selected at the shortest part of the plastic filling process to reduce the pressure loss and facilitate the exhaust of the mold;
（6）. Avoid opening a gate near the slender core to avoid the direct impact of material flow on the core, resulting in deformation, dislocation or bending;
（7）. The gate size is determined by the product size, geometry, structure and plastic type. The small size can be taken first and then corrected according to the mold test condition;
（8）. Through mold flow analysis or experience, it can be judged whether the joint line of the product caused by the gate position affects the appearance and function of the product, which can be solved by adding a cold material hole;
（9）. The first mock exam is the first mock exam. The same product is symmetrical in the casting process. For different products in the same mold, the best product will be placed near the main road.
2、 Key points for attention
. Don't just focus on product design and ignore plastic mold manufacturing
When developing products or trial production of new products, some users often only focus on product research and development in the initial stage, ignoring the communication with plastic mold manufacturers. After the preliminary determination of the product design scheme, contact with the mold manufacturer in advance has the following three benefits:
(1) It can ensure that the designed products have good forming process and will not modify the finalized design because the parts are difficult to process.
(2) The mold manufacturer can make design preparations in advance to prevent improper consideration in a hurry from affecting the construction period.
(3) To make high-quality plastic molds, only the close cooperation between the supplier and the demander can finally reduce the cost and shorten the cycle.
. Don't just look at the price, but consider the quality, cycle and service
(1) There are many kinds of molds, which can be roughly divided into ten categories. According to the different requirements of part materials, physical and chemical properties, mechanical strength, dimensional accuracy, surface finish, service life, economy and so on, different types of dies are selected for forming.
(2) High precision molds need to be processed by high-precision CNC machine tools, and there are strict requirements for mold material and forming process. CAD / CAE / CAM mold technology needs to be used for design and analysis.
(3) Due to the special requirements of some parts during molding, the mold also needs to use advanced processes such as hot runner, gas assisted molding, nitrogen cylinder and so on.
(4) The manufacturer shall have CNC, EDM, wire cutting machine tools and CNC profiling milling equipment, high-precision grinder, high-precision three coordinate measuring instrument, computer design and related software.
(5) Generally, large stamping dies (such as automobile cover dies) should consider whether the machine tool has blank holder mechanism, even edge lubricant, multi station progressive, etc. In addition to stamping tonnage, punching times, feeding device, machine tool and die protection device should also be considered.
(6) The manufacturing methods and processes of the above molds are not possessed and mastered by every enterprise. When choosing a cooperative manufacturer, we must understand its processing capacity. We should not only look at the hardware equipment, but also combine the management level, processing experience and technical force.
(7) For the same set of molds, there is sometimes a big gap in the quotation of different manufacturers. You should not pay more than the value of the mold, nor less than the cost of the mold. Mold manufacturers, like you, should make reasonable profits in their business. Ordering a set of molds with a much lower quotation will be the beginning of trouble. Users must start from their own requirements and comprehensively measure.
. Avoid multi head cooperation and try to integrate plastic mold making and product processing
(1) With qualified molds (qualified test pieces), batch qualified products may not be produced. This is mainly related to the selection of machining machine tools, forming process (forming temperature, forming time, etc.) and the technical quality of operators.
(2) With good molds, we should also have good forming and processing. It is best to cooperate in one-stop and avoid multi head cooperation as far as possible. If the conditions are not met, it is necessary to select one party to be fully responsible and write it clearly at the same time.
