Electrostatic grounding of metal pipes

The answers to the two questions posed by the original poster are clear: a flange connection is necessary, and the pipes must be properly grounded! Similar problems often occur among the technical and operational staff on site; they do not understand the anti-static regulations in this industry. They assume that the flanges are connected using conductive steel bolts, which already constitute an electrical path, so there is no need to add copper wires for bridging. Some even refrain from using such bridging wires, handle their tasks perfunctorily, and fail to maintain these connecting wires properly or in a timely manner. In fact, to effectively prevent the \"secondary discharge\" caused by lightning strikes, the resistance between the connection flanges must be sufficiently low. Although bolted connections can meet the requirements for electrostatic discharge in valves and pipelines, factors such as bolt corrosion and changes in air humidity prevent them from satisfying the low-impedance requirement between flanges around the clock. As a result, it is not possible to ensure that the static charges on the upper and lower flanges are discharged simultaneously immediately after a lightning strike, and thus effective prevention of \"secondary discharge\" cannot be achieved. With metal bolts and steel structural pipe racks, it is not guaranteed that \"there must be a sufficiently low resistance between the mating flanges.\" When the flanges are connected using 5 or more bolts, it is not necessary to use metal wires for bridging, but an electrical path must still be established. ”The electrical pathways in this text are very important; generally, flanges with 4 bolts or fewer require bonding to prevent static electricity issues. One must not take static electricity lightly, as even a small amount of it can cause tanks holding tens of thousands of cubic meters of oil to explode into the air. . As for what secondary discharge is, just search on Baidu; it’s actually something from middle school physics.

What needs to be done is to connect them with copper sheets, in order to prevent excessive resistance due to rust.

When the flange is connected with 5 or more bolts, it is not necessary to use a metal wire for bridging, but an electrical path must be established. How to ensure an electrical path? Is it necessary to carry out specialized electrical grounding? ? ? ?

In my opinion, for metals that are prone to rusting or in harsh environments, it’s better to add a metal bridge; once rust forms, the electrical conductivity decreases.