PlasticA mold is mainly composed of gating system, molding parts and structural parts. The casting system and molding parts are the parts directly in contact with plastic, and change with plastic and products. They are the most complex and changeable parts in plastic mold, which require the highest processing finish and precision.

The plastic mold pouring system refers to the flow passage before the plastic enters the cavity from the nozzle, including the main channel, cold material hole, shunt channel and gate, etc. Forming parts refer to various parts forming the shape of products, including moving mould, fixed mold and cavity, core, molding rod and exhaust port.

1、 Mainstream Road

It is a passage in the mold connecting the injector nozzle to the shunt channel or cavity. The top of the main channel is concave to connect with the nozzle.

The diameter of the inlet of the main channel should be slightly larger than the nozzle diameter (0.8mm) to avoid overflow and prevent the blocking of the two due to the improper connection.

The diameter of the import is determined by the size of the product, generally 4-8mm. The diameter of main channel should be expanded inwards by 3 ° To 5 ° Angle for release of runner burden.

2、 Cold material hole

It is a hole at the end of the main channel to catch the cold material produced between two injections at the end of the nozzle, so as to prevent the blocking of the shunt or gate. If the cold material is mixed into the cavity, the internal stress will easily be produced in the product.

The diameter of cold material hole is about 8-l0mm and the depth is 6mm. In order to facilitate demoulding, the bottom of the demoulding rod is usually undertaken. The top of the release rod should be designed as a zigzag hook or a groove to allow the main channel to pull out the main duct burden smoothly.

3、 Diversion channel

It is a channel in a multi slot mode which connects the main channel and each cavity. In order to make the molten material fill all cavities at equal speed, the distribution of the shunt channel on the mold should be symmetrical and equal distance. The shape and size of the cross section of the shunt channel have an influence on the flow of plastic melt, the release of products and the difficulty of mold manufacturing.

If the flow is equal, the flow resistance of the runner with circular section is the least. However, because the surface of the cylindrical runner is small, it is not good for the cooling of the burden of the shunt, and the shunt must be set on the two half die, which is both laborious and easy to align.