The following are examples of the more common damage/defects that may occur:
- Fractures at the boundaries of corrugations and bulkhead stools, particularly in way of shelf plates, shedder plates, deck, inner bottom, etc.
- Buckling of the plating/corrugations, leading to the failure and collapse of the bulkhead under water pressure in an emergency situation. .
- Excessive wastage/corrosion, in particular at the mid-height and bottom of bulkheads, which may look in deceptively good condition. This is created by the corrosive effect of cargo and environment, in particular when the structure is not coated.
In this respect special attention should be given to the following areas:
- Bulkhead plating adjacent to the shell plating;
- Bulkhead trunks which form part of the venting, filling and discharging arrangements between the topside tanks and the hopper tanks;
- Bulkhead plating and weld connections to the lower/upper stool shelf plates;
- Weld connections of stool plating to the lower/upper stool shelf plates and inner bottom;
- In way of weld connections to topside tanks and hopper tanks;
- Any areas where coatings have broken down and there is evidence of corrosion or wastage. It is recommended that random thickness determination be taken to establish the level of diminution;
- Other structures, e.g., diaphragms inside the stools, particularly at their upper and lower weld connections.