... mating various vacuum pump, such as water ring pump, lobe pump, rotary vane pump, plunger pump, etc.. In accordance with vacuum pump features and ... 1. Water ring pump, lobe pump, rotary vane pump, plunger pump;2. Oil vapor recycle system, hospital negative pressure system, enviromental program, ... 5. Monitor high and low voltage of refrigeration system, convenient for users to control the internal ...