Based on the previously discussed service life and routine maintenance of grooved pipe fittings, the following key points should be observed during replacement:
Preliminary Preparation and Safe Operation
Medium Drainage: Before replacement, close the corresponding pipeline valves and drain any residual medium; for pressurized pipelines, ensure full depressurization before commencing work.
Tool Selection: Use a preset torque wrench or socket wrench; apply force perpendicular to the thread axis to avoid bolt seizure caused by excessive or improper force.
Work Area Preparation: Clear debris from the surrounding area; implement fire safety measures in advance if hot work (open flame) is required.
Removal of Old Components
Systematic Disassembly: Alternately loosen the coupling bolts on both sides; carefully remove the old coupling and worn gasket, avoiding forceful prying that could damage the pipe ends.
Pipe End Preparation: Thoroughly grind the pipe ends with sandpaper or a file to remove residual rust and burrs, ensuring the end face is perpendicular to the pipe axis.
Installation Standards for New Components
Gasket Inspection: Inspect the new rubber gasket for damage before installation; a small amount of silicone grease may be applied for lubrication. After installation, verify there is no wrinkling or twisting; any wrinkled gasket must be replaced with a new one.
Bolt Tightening: Tighten the bolts on both sides in an alternating diagonal pattern; maintain torque within the manufacturer's recommended range of 30–40 N·m to avoid crushing the rubber gasket through overtightening.
Groove Verification: If the existing pipe groove is deformed, re-roll the groove; strictly control the groove depth to ensure sealing performance is not compromised by a groove that is too deep or too shallow.
