S9074-AR-GIB-010/278
The 75 or 50 percent minimum coverage is defined as casting areas in the film which are within the specified density limits and are interpretable. It is not the intent that only 75 or 50 percent of casting be radiographed and that any specific area be excluded. Noncritical areas need not be radiographed when approved. 12.5.4 Extent of MT or PT inspection for ferrous castings. Ferrous castings for which radiography is required in accordance with tables XIII. XIV. or XV shall receive in addition to radiography. 100 percent MT or PT inspection of all accessible areas. Ferrous castings for which MT or PT inspection is required in accordance with tables XIII. XIV, or XV and radiography is not specified shall receive 100 percent MT or PT inspection of all accessible surface areas. Static loaded ferrous castings shall received 100 percent MT or PT inspection of all accessible surfaces which are subject to static loading. 12.5.5 Extent of PT for nonferrous castings. Except as required by footnote 3 to table XIII and footnote 4 to tables XIV and XV. nonferrous castings do not require PT inspection. 12.5.6 Records for NDT of Castings Records of casting inspection by VT and NDT methods shall be as follows:
Casting identification. including heat &r and where appl icable. heat treatment lot nmber , drawing nrmber and seri a1 mr.
(a)
Material identification by specification number and class or alloy.
(b)
Inspection methods and results.
(c)
For submarines. extent of inspection and traceability.
(d)
Inspection records for castings shall include casting repair records as specified in 13.2.10.
12.6 NDT Responsibilities 12.6.1 Designer responsibility. When 100 percent inspection is not required. the casting designer shall implement the requirements of 12.5.3 and 12.5.4 by identifying areas requiring NDT on engineering drawings by appropriate assignment of symbols conforming to AWS A2.4. 12.6.2 Contractor responsibility. The foundry or activity performing the radiography shall prepare the radiographic shooting sketch in accordance with MIL-STD-271 based on requirements established by the designer (see 12.1.1). Prior to preparation. the design requirements for radiography shall be reviewed to ensure feasibility from the fabricator point of view. When disagreements arise between the designer and foundryman concerning areas for which radiography is required, but considered impractical by the foundryman. a meeting of both parties shall be arranged to resolve any controversial issues. Drawings shall be modified to reflect the decisions mutually reached by the designer and foundryman. Since a variety of
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