REPAIR OF A CORRODED/ HOLED FRESH WATER COOLER END COVER

• If the end cover is holed and leaking while the cooler is in service, the leak must be controlled to prevent loss of cooling water and contamination.
• Isolate the cooler (close the inlet/ outlet valves) if possible, or reduce the flow/ pressure to minimise the leak.
• Apply a temporary repair to the hole: e.g. fit a temporary patch/ clamp over the hole (a rubber/ gasket patch held by a clamp/ band), or drive a tapered plug/ wooden plug into the hole, or apply a quick-setting repair compound/ epoxy over the hole (after cleaning and drying the surface).
• If the hole is in a flange/ joint, tighten the joint or fit a gasket/ packing.
• Monitor the cooler and the cooling water system; arrange for a permanent repair at the earliest opportunity (in port/ at the next stop).
• If the leak cannot be controlled, the cooler must be taken out of service and the engine/ system operated on the standby cooler or at reduced load.

• Isolate and drain the cooler, and remove the end cover.
• Clean the end cover and assess the extent of the corrosion/ holing.
• Repair options:
• Weld the hole/ corroded area (after cleaning and preparing the surface) using the correct welding procedure/ filler for the cover material; then machine/ grind flush and pressure-test.
• Fit a patch/ doubler plate over the holed area (welded or bolted) to restore the thickness.
• If the corrosion is extensive, renew the end cover (or the affected section).
• Apply a corrosion-resistant lining/ coating (epoxy) to the repaired cover to prevent recurrence.
• Pressure-test the repaired cover (and the cooler) to confirm it is leak-tight before returning to service.
• The repair must be effective, practicable and innovative, and carried out to the maker's/ Class requirements.