How to accurately cut the valve motor head and valve body insulation

When ordering, it is necessary to check whether the insulation of the valve head and the valve body is done well. This can avoid the impact of the electric head grounding on the cathodic protection, and this similar cut-off valve is used in the second phase of the Hazhong Road project to avoid the grounding short circuit of the valve body. If it is not possible to insulate the electric head from the valve body, a zinc anode can be installed at the electric head, and the electric head is grounded through the zinc anode. Since the zinc anode has a potential of -1.10VCSE, only a small amount of current will be lost and will not have a large impact on the cathodic protection. The method of installing a grounding battery between the valve head and the grounding network is relatively simple and convenient to operate. A grounded battery is actually two zinc rods separated by an insulating block, and because the zinc rods themselves have a low potential, they do not lose too much cathodic protection current. One zinc rod is connected to the valve head and the other zinc rod is connected to the grounding net. Because there is an insulating block between the two zinc rods, it will not cause, and because the two zinc rods are backfilled with special fillers, the resistance is very small, and when there is lightning strike or fault voltage, it can be discharged into the grounding network in time.