For high adsorbent such as PMMA, PC, AC or high adsorbent with poor thermal stability, in order to reduce the adsorption force and hysteresis time of the adsorbent, it is not necessary to check the reverse ring, but such adsorbent will produce reverse flow and extend the pressure holding time. Screw head requirements: ① screw head flexible, smooth; (2) The matching gap between the check ring and the cylinder should be appropriate, that is, to prevent melting, but also flexible; ③ The top ten brands of screw head injection molding machine have enough circulation, and at the same time ensure that the end face of the reverse ring has a return force, so that the injection can be quickly closed; ④ the structure is easy to disassemble and assemble, easy to clean; ⑤ The expansion of the screw head is opposite to the expansion direction of the screw head to prevent the screw head from loosening when pre-plastic. (3) Cylinder (1) : the structure of the cylinder, the cylinder is an important part of the plasticizing parts, the internal screw, the external heating ring, to withstand the role of composite stress and thermal stress.

Screw hole 3 installed thermocouple, domestic brand injection molding machine should be in close contact with the thermocouple to prevent floating, so as not to affect the temperature measurement accuracy.