scope:

This procedure is to be used for in-service inspections carried out outside of the Long Overhaul Period. This process is used to gauge the overall health of all Nickel Aluminium Bronze (NAB) contained in the NAB Register of a submarine by detailed examination of a sample of NAB castings.

Castings are to be chosen for inspection from the assessments carried out using NABWETLIFE or as requested by the Design Authority.

Part 1 of this Defence Standard covers the policy for the recording and updating of Nickel Aluminium Bronze castings fitted in submarines to meet the First Level Quality Assurance requirements in accordance with SSP 25.

Part 2 of this Defence Standard is to be used for the validation of all Submarine First Level castings made of Nickel Aluminium Bronze (NAB) manufactured to Defence Standard 02-747 Part 1, 2 or 4. It is to be used to establish a baseline of data for any weld repairs, wall thickness measurements and the integrity of the casting at manufacture.

Part 3 of this Defence Standard is to be used for the revalidation of Submarine First Level castings made of Nickel Aluminium Bronze (NAB) manufactured to DGS 8520, DGS 348 or Defence Standard 02-747 Part 1, 2 or 4 which have had service use involving contact with sea water.