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1. Function of static electricity bonding: Static electricity bonding is used to eliminate static electricity and prevent the generation of static sparks. It involves using metals with good electrical conductivity to connect two flanges or valve flanges together, thereby grounding the pipeline. Flanges are usually coated with anti-corrosion materials, which can lead to poor contact and the formation of sparks. Static electricity bonding is employed to prevent accidents by providing a pathway for the accumulated charge to be discharged. 2. Where are static electricity bonding connections required? Article 80 of the \"Regulations on Safety Inspection of Pressure Pipelines – Industrial Pipelines\" (TSGD0001–2009) specifies the following regarding anti-static measures using flange connections: For pipelines that require static electricity grounding, it is necessary to measure the resistance values between each connection point as well as the resistance value of the pipeline system relative to the ground. When the stress exceeds the requirements specified in the \"Code for Pressure Piping – Industrial Piping\" (GB/T20801-2006) or in the design documents, bypass wires (between flanges or threaded joints) and grounding leads shall be installed. As can be seen from this clause, to determine whether a bypass wire is needed for the flanges, it is necessary to measure the resistance between them; if the resistance value exceeds the specified limit, a bypass wire must be used. Clause 10.12.1 of the \"Code for Pressure Piping – Industrial Piping, Part 4: Fabrication and Installation\" (GB/T20801.4-2006) stipulates that for pipelines requiring static grounding, good electrical conductivity must exist between various sections of such pipelines. When the resistance value between each pair of flanges or threaded joints is greater than 0.03Ω, a wire bridge should be provided. Article 7.13.1 of the \"Code for Construction of Industrial Metal Piping Projects\" (GB 50235—2010) stipulates that for pipelines for which static electricity grounding is required, if the resistance value between each pair of flanges or other joints exceeds 0.03 ohms, a bonding wire should be installed. It can be seen that to determine whether metal flanges on industrial pipelines need to be bonded together, it is necessary to measure the resistance value between the flanges. When the resistance between the flanges exceeds 0.03Ω, a wire bridge should be installed. 3. How should static grounding be done? The \"Technical Code for Static Grounding Design in Chemical Enterprises\" (HGJ28-90) has now been renumbered as HG/T20675-1990. Section 2.7.5 of this specification states that when metal flanges are fastened using metal bolts or clamps, it is generally not necessary to install additional electrostatic connection wires. Under corrosive conditions, it is necessary to ensure that there are at least two contact surfaces between the bolts or clamps; rust and oil should be removed prior to installation, and anti-loosening nuts should be used during installation. The \"Explanations for the Preparation of Technical Specifications for Static Grounding Design in Chemical Enterprises\" provide the following explanation for clause 2.7.5: Based on the practical experience of many organizations, metal flanges connected by metal bolts possess sufficient static conductivity simply through the connection of those bolts. The installation requirements under corrosive conditions are intended to ensure conductivity. The \"Code for Design of Static Grounding in Petrochemical Industries\" (SH3097-2000), as a corporate standard, is stricter than **national standards and industry standards. Paragraph 4.3.3 of this standard specifies that in piping systems, when metal flanges are fastened using metal bolts or clamps, it is generally not necessary to install additional electrostatic connection wires; however, it is essential to ensure that there is good electrical contact between at least two of the bolts or clamps. Article 14.2.14 of the \"Code for Design of Oil Depots\" (GB 50074-2014) stipulates that flange connections of oil (oil and gas) pipelines shall be bridged. When connected by no less than 5 bolts, bypass wiring is not required in non-corrosive environments. Article 10.3.3 of the \"Code for Design and Construction of Automobile Fuel and Gas Stations\" (GB 50156—2012) stipulates that in areas prone to explosion, metal wires should be used for bonding at connections such as flanges on oil, liquefied petroleum gas, and natural gas pipelines, as well as at both ends of hoses. When there are no fewer than 5 connection bolts on the flange, bypass wiring is not required in non-corrosive environments. Article 6.12.2 of GB50235-2010 \"Code for Construction and Acceptance of Industrial Metal Piping\" stipulates that when the earth resistance value of the piping system exceeds 100Ω, two grounding leads shall be provided. The grounding lead should be welded. SH3501-2002 \"Code for Construction and Acceptance of Toxic and Flammable Media in Petrochemical Industries\": Article 6.2.16 stipulates that for stainless steel pipes requiring static electricity grounding, the wire bridging or grounding leads shall use stainless steel plates as a transition element; they must not be connected directly to the stainless steel pipe.