Cracked sea water line at berth: the overnight repair sequence, step by step
A specific defect, a specific night, and the sequence that closes it before the morning watch — with class in the loop the whole way.
A cracked sea water line found on a routine watch inspection at 20:30. Vessel scheduled to sail at 08:00. Below is the sequence we run for exactly this failure.
The defect
Circa 200 mm circumferential crack on a 4" sea water suction line to a main engine cooler, isolatable at both ends. Corroded, thinned original pipe, dry inside the isolated section.
20:45 — attendance and containment
On board within 30 minutes of the call. Chief Engineer confirms isolation is intact and the line can stay drained overnight. Class notified — surveyor available for morning attendance.
21:10 — scope agreed
Crop the affected section: approximately 800 mm, valve to elbow. Fabricate insert pipe in the workshop from a spec-matched stock length. WPS on file, welder certified, consumables logged.
21:40 — measurements and preparation
Exact lengths and angles taken. Pipe spool cut, bevelled and dry-fitted in the workshop. Photo of the marked-up spool with the vessel and defect number.
23:15 — cropping on board
Hot work permit signed, fire watch briefed. Cropped section removed. Edges cleaned and prepared for welding.
00:30 — root pass and fill
Root pass welded on the first joint. NDT-friendly technique — no lack of penetration. Fill and cap passes.
02:45 — second joint
Same sequence on the elbow-side joint. Photos between each pass for the report.
04:15 — hydrotest
System re-filled and pressure tested to 1.5 × working pressure. Held for 30 minutes. No weep.
06:00 — class attendance
Surveyor on board with the class file open. Visual and NDT on both welds. Accepted. Certificate updated on the spot.
07:30 — clean and clear
Site cleaned, PMS updated, repair report signed and handed to the Chief Engineer.
08:00 — pilot on board
Vessel sails on time.
What made it close overnight
A welder available and awake at 22:00. A pipe stock the right spec on the shelf. A class file that was ready before the survey was asked for. No heroics — a process.
If you have a piping or plating defect that must close before morning, call the line. We are staffed for exactly this shift.