Plastic product molding cycle

- Feb 15, 2019-

     Molding cycle actually includes the following parts: molding cycle: molding cycle directly affects labor productivity and equipment utilization.


      Therefore, in the production process, should be in the premise of ensuring quality, as far as possible to shorten the molding cycle of the relevant time.


     In the whole molding cycle, injection time and cooling time are the most important, which have a decisive influence on the quality of products.The filling time in the injection time is directly inversely proportional to the filling rate, and the filling time in the production is generally about 3-5 seconds.


    The pressure holding time in the injection time is the pressure time of the plastic in the cavity, which takes up a large proportion in the whole injection time, generally about 20-120 seconds (especially thick parts can be up to 5-10 minutes).Before the melting material at the gate is frozen, the pressure holding time has an impact on the accuracy of the product size.Pressure holding time also has an optimum value, which is known to depend on the feed temperature, mold temperature and the size of the runner and gate.If the size of the runner and gate and the process conditions are normal, it is usual to obtain the minimum shrinkage range of the pressure value shall prevail.The cooling time depends on the thickness of the product, the thermal and crystallization properties of the plastic, and the temperature of the mold.


     The end of the cooling time, should be in order to ensure that products demoulding does not cause changes as a principle, cooling time is generally about 30~120 seconds between, cooling time is too long is not necessary, not only reduce the production efficiency, the complex parts will also cause demoulding difficulties, forced demoulding even produce demoulding stress.Other times in the molding cycle are related to the continuity and automation of the production process and the degree of continuity and automation.