Installation standards and common problems of ball valves in the petrochemical industry

I. Core Installation Specifications

Pre-installation Preparation: Verify that the ball valve model matches the working conditions. Ensure the valve body and sealing surfaces are undamaged and have passed pressure tests. Remove weld slag, rust, and other impurities from the pipeline to prevent scratches on the sealing surfaces.

Installation Process Requirements: Install in accordance with the medium flow direction marking. Ensure the valve stem is vertically upward. For flange connections, fasten bolts evenly to prevent the valve body from deformation due to uneven force. For welded ball valves, use argon arc welding for backing to prevent weld slag from entering the valve cavity.

Specifications for Special Working Conditions: For highly corrosive media, select fluorine-lined or Hastelloy ball valves. Avoid direct contact with other metal components during installation. For high-temperature conditions (>200℃), reserve gaps for thermal expansion and contraction, and install heat insulation sleeves at the valve stem.

Safety Protection Requirements: For ball valves in flammable and explosive medium pipelines, conduct anti-static grounding. For remotely controlled ball valves, reserve maintenance space and ensure wiring complies with explosion-proof standards.

II. Common Troubleshooting

Internal/External Leakage: External leakage is mostly caused by aging flange gaskets or loose bolts—replace gaskets and fasten bolts evenly. Internal leakage is usually due to scratched sealing surfaces or deformed balls. Check for the intrusion of granular media; if necessary, lap the sealing surfaces or replace the balls.

Opening/Closing Jamming: Mostly caused by pipeline stress transmitted to the valve body, impurity blockage in the valve cavity, or valve stem rust. Adjust pipeline supports to eliminate stress, disassemble the valve body to clean impurities, and apply high-temperature anti-rust grease to the valve stem.

Malfunction of Remote-Control Valves: For pneumatic ball valves, check the air supply pressure and whether the solenoid valve is blocked. For electric ball valves, inspect the power supply and limit switches to prevent motor burnout due to overload.

Corrosion Damage: When the medium contains sulfur, chlorine, or other corrosive components, valve body corrosion is likely to occur. Verify if the material selection matches the conditions; if necessary, replace with corrosion-resistant alloy materials and shorten the inspection cycle.

III. Key Notes

After installation, conduct strength tests and sealing tests before putting the valve into use. Focus on valve body temperature, sealing surface status, and valve stem displacement during daily inspections. Shut down immediately if abnormalities are found to prevent safety accidents caused by worsening working conditions.