According to the method of keeping the plastic in the melting state in the runner, the handle mold of the hot runner milk box can be divided into two types: adiabatic runner injection mold and hot runner injection mold, namely:
1、 Adiabatic channel
The handle mold of the injection milk box with the insulating layer adopts the larger interface size of the main flow channel and the shunt channel, and the plastic is contacted with the flow channel wall to form the thermal insulation effect of the condensation layer, so that the plastic at the center of the flow channel can always maintain the melting flow, so that the molten material can smoothly enter the mold cavity through the flow channel under the action of injection pressure, so as to meet the requirements of continuous injection.
(1) Adiabatic sprue
Adiabatic sprue, also known as wellhead nozzle, is the simplest adiabatic runner, which is suitable for single cavity injection mold.
(2) Adiabatic shunt
Thermal insulation runner is also called multi cavity thermal insulation runner, which has two forms: direct gate and point gate.
2、 Heating channel
The heating flow is to leave the red paper heater in or near the flow channel. Between the nozzle and gate of the injection molding machine, the gating system of the injection molding machine is in a high temperature state through heating, so that the plastic in the injection molding machine will always remain molten in the production process.
(1) Extension nozzle
The extension nozzle is the simplest heating channel. It is a special nozzle, which can be in direct contact with the gate part on the milk box handle mold after the extension of the ordinary nozzle. The machine can also be equipped with a water heater to compensate the heat dissipation of the nozzle after stretching, or make its temperature higher than the material temperature according to special requirements. The retracting and releasing port is only applicable to the handle mold structure of single cavity milk box.
(2) Valve gate hot runner
When plastic with low viscosity is injected into hot runner, valve gate can be used to avoid casting and wire drawing.
(3) Multi cavity heating channel
This milk box handle mold has many structural forms, but it can be roughly divided into external heating type and internal heating type.
