Inspection Cycle: Inspect seal condition every 3 months, focusing on gaskets at flange connections, sight glass joints, and shell interfaces (typically rubber or PTFE material).
Inspection Items: Observe seals for signs of aging (e.g., hardening, cracking, loss of elasticity), deformation, wear, or leakage traces.
Replacement Criteria: Immediately replace any seals exhibiting the above issues with new seals of identical specifications and material. During replacement, ensure the sealing surface is clean and free of contaminants. Tighten connecting bolts evenly to prevent seal failure due to over- or under-tightening.
Periodic Pressure Testing
Testing Cycle: Conduct pressure testing at least once annually. For high-pressure pipeline systems (e.g., power transformer oil circuits), testing every 6 months is recommended.
Test Method:
Close the upstream and downstream valves of the sight glass to isolate the test section.
Slowly introduce a medium (or compressed air) equivalent to the pipeline's working pressure. Maintain pressure for 30 minutes while observing the sight glass housing, viewing window glass, and connections for leaks, deformation, or other abnormalities.
Test pressure must not exceed 1.2 times the equipment's rated working pressure to prevent overpressure damage.
Inspection and Replacement of Sight Glass
Inspection Frequency: Conducted concurrently with each cleaning, focusing on cracks, scratches, damage, or loose edge seals.
Replacement Criteria:
Immediately replace any glass exhibiting cracks (even minor ones) to prevent rupture under pressure causing medium leakage.
Use tempered glass or tempered borosilicate glass of the same model and pressure rating for replacement. Before installation, ensure the glass surface is free of contaminants, the sealing gasket fits tightly, and bolts are evenly tightened.
