Abstract: Simulation software MoldFlow was used to carry on the simulation to the different gate loca tion,andthecooling system of the magnetism therapy meter casing etc, and the injection pressure, clamping forceand weld line to the different gate location while filling were performed to analyze. Re-sults indicate that best gate location is in the outside of parts, and single gate. Several straight formulae cooling circuits were adopted to cool，and the disposed schemes were simulated. Results reveal that cool-ing result of scheme 2 is to be better, the most great difference in temperature of the core and cavity within 20℃，temperature profilesevenlyand makes pieces of deformation amount little. Finallly injec- tion experiment has been completed and high-quality products were obtained, which verified the rational- ity of the simulation.

Key words: plastics injection mold, injention pressure, clamping force, poling system;optirnization design