The main function of the industrial plug is to keep the circuit unobstructed, so that the cable is kept sealed, to ensure that the insulation level of the cable joint meets the requirements, which is its safe and reliable operation. If the sealing performance is not good, not only oil leakage will cause oil or water to enter, but even moisture in the environment will seep into the cable, reducing its insulation and making it more prone to electric shock or splash. Therefore, connector tightness is a very important property.