Injection molding machine variety, but its basic operation program is not much difference, with screw injection machine is described as an example.
  1.closing, locking. Start the injection molding machine, dynamic model with low pressure rapidly to the fixed mould approach, going to contact, the power system automatically switches to the low speed and high pressure, so that the moving mold and the fixed mold smoothly and the fixed mold injection mold cavity closure, form, then switch to high pressure, to lock the mold, ready for injection.
  2.injection. In the mold locking, injection device forward, the nozzle and mold sprue tightly, the pressure oil into the injection cylinder, screw and connected with the piston rod of the hydraulic cylinder, in high pressure hydraulic oil, the head of the screw melt speed and pressure into the cavity and fill the. The effect on the melt on the pressure is called the injection pressure.
  3.pressure. Inject melt mold cavity, by cooling effect of low temperature of mold, rapid temperature decrease, the molten material will produce contraction. At this time, the screw on the melt should still maintain a certain pressure, the molten material of the head can replenish melt lack due to shrinkage cavity in, this pressure is called pressure.
  4.plastic solidification. When the melt temperature continues to drop, the melt at the gate first solidification, such, melt in die cavity was not from the gate at reflux may. At this time, the hydraulic cylinder pressure to remove, clamping force can also be withdrawn, melt in the mold cavity cooling stereotypes.
  5.pre plastic. In the melt is cooling at the same time, the rotation of the screw rod under the action of the driving mechanism, the future of the moving granular plastic material hopper, and the plasticizing, was pushed to the head of the screw, the screw back pressure. When the screw to the measurement scale, which marked the melt screw head aggregation has reached the quantitative requirements, at this time, the travel switch is touched, screw in the driving mechanism of power under which stops rotating, ready for the next injection time.
  6.The  release. When the plastic in the mold cavity after curing molding, injection device can retreat, the nozzle from the mould temperature is low, clamping device is opened, the demoulding mechanism of top out of plastic parts, injection molding will complete a cycle of work.