Temperature control
Generally speaking, LSR molding is suitable for electric heating, which is usually heating by belt heater, barrel heater or heating plate. The key is to make the temperature field of the whole mold evenly distributed to promote the LSR uniform curing. It is an economic and effective heating method when the oil temperature is controlled for heating on large moulds.
It is beneficial to reduce the heat loss by covering the die with heat insulation plate. The unfitness of any part of the hot mold may make it suffer great temperature fluctuation between the operation procedures, or cause gas escape. If the surface temperature drops too low, the curing speed of the compound will slow down, which often makes the product unable to demould, causing quality problems. A certain distance shall be kept between the heater and the parting line to prevent the formwork from warping and deformation, and the rubber overflow burr shall be formed on the finished product.
If the mold of cold runner system is designed, the hot end and cold end must be completely separated. It can be made of specially made chin alloy (such as 3.7165 [tia16v4]), because its thermal conductivity is much lower than other steels. For an integral mold heating system, the heat shield shall be set between the mold and the mold support plate to minimize the heat loss.
Proper design and conception can ensure LSR injection molding, in this mold is very important. The above mold design principle aims to make the rubber fill the mold cavity, shorten the curing time, improve the quality of the finished product, and increase the output, so that the silicone rubber processor can obtain good economic benefits.