Flange face for dirt/oil before gasket not checked

Fix the gasket condition before bolting/sealing: not checking flange face for dirt/oil before gasket. The gasket needs clean contact and continuity at the flange/corners.

Protect the gasket and flange face before tightening. A dirty, folded, missing, crushed, or broken gasket becomes a leak path.

Stop if

• Ask when connector type, gasket, cleat/bolt schedule, pressure class, or manufacturer detail is unclear.

Watch out

• Do not bolt over dirty, wet, folded, missing, or displaced gasket.

Check

• Clean the flange face
• Check gasket continuity and corners
• Make sure the gasket stayed in place while lifting

Steps

• Align the duct sections square.
• Check flange faces, corners, gasket, and cleats/bolts.
• Fix damage or missing parts before tightening.
• Tighten or cleat evenly per project/manufacturer detail.
• Focus on the actual issue: not checking flange face for dirt/oil before gasket.

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