Right now, two platen injection molding machine is more and more popular in the market (for example, Haitian two platen injection machine) ,especially for the production of big Auto parts, big dustbin and other product which need big mold open stroke.
What’s the difference between two platen injection molding machine and traditional three platen injection machine?
the main difference is the mold clamp system.
two platen machine mainly use the direct pressure mold clamp system, see below schematic diagram.
Direct pressure mold clamp system use the clamp cylinder to generate the clamp force and keep mold closed well.
When start mold closing, the clamp nut opened,the mold close cylinder work. when the moving mold platen moved to the groove position of the tie-bar, the clamp nut closed,tie-bar and moving mold platen are closed and connected well. Then the mold clamp cylinder will work to generate the clamping force.
by this structure,it will need big clamp force from the clamp cylinder, so usually the clamp cylinder is very big. According to our experience, the most big problem is the clamp cylinder leak oil and damaged, it will bring much repair cost and time.
However,compared to the normal toggle clamp system, direct-pressure clamp system has smaller size. So usually two platen injection molding machine need smaller space than 3 platen injection moulding machine, and better mold clamp precision.
B) traditional three platen injection moulding machine
traditional three platen injection moulding machine use the toggle link system to generate the clamp force.
by this way, even use small diameter clamp cylinder, it can also generate big clamp force and fix big mold. But because the toggle system consist of many links, there will be friction and wearing problem of the toggle system. So the lubrication to the toggle system is very important for the machine’s lifetime.