S9074-AR-GIB-010/278
This plan shall be submitted for review and written notification of acceptance shall be received from NAVSEA prior to the start of fabrication. Any proposed technical changes to the plan shall be promptly provided to NAVSEA for review. Where evidence is provided to show that similar fabrications have been previously produced to this document or that the activity has extensive titanium fabricating experience, NAVSEA may, at its discretion, accept procedures established by that activity in lieu of all or portions of the requirements of this paragraph. 30.2 Facilities.The activity and/or its subcontractor(s) shall prepare and obtain NAVSEA approval of a procedure that establishes facility requirements for the fabrication of titanium. This procedure shall include the controls to be established for the welding and fabrication of titanium to preclude contamination. Although. the use of a dedicated facility is recommended, the activity may establish temporary fabrication areas for titanium welding. The procedure shall address: equipment necessary for materials handling , envirommtal control . welding. machining. conditioning and cleaning. inert gas distribution, heat treating. and nondestructive evaluation. The procedure shall provide requirements that ensure that the welding area is restricted from general traffic. and is protected from winds and draft, dirt, smoke, grinding residues, welding and machining operations on other materials. and other airborne contaminants. All equipment to be used in the titanium welding area shall be blown clean and wiped to remove accumulated dust and dirt before being brought into that area. Pneumatic tools shall not be used in the area of welding or fabrication operations unless requirements specified in the procedure preclude contamination of welds. base materials, and filler materials. A regular scheduled cleanup of welding areas and temporary areas (while maintained for use) shall be established. Clean up is to include use of vacuum cleaners exhausting outside the area rather than items such as brooms. Controls for the use of nondedicated materials, equipment. and facilities (e.9.. preheat funrace for hot forming) shall also be included in the procedure to ensure that such use does not contaainate the titanium or titanium alloy. 30.2.1 Materials. All materials Involved in the fabrication or inspection of titanium and titanium alloys. including consumables such as shielding gases. cleaning agents. and dye penetrants. shall be certified as to purity and conformance to specification and/or fabrication plan. Shielding and purge gases shall be argon. helium or mixture thereof. All shielding and purge gases used for welding or for heat treating (vacuum furnace purging) shall have (1) a purity of at least 99.995 percent and (2) a dew point of -60F or less at the work piece (weld) or purge exit . Shielding gas hoses for welding shall be new or shall have been used to inert welding shielding gas only. Records of certification shall be maintained. 30.2.1.1 Dew point of shielding and purge gases shall be tested at the beginning of each shift or whenever gas flow is interrupted, except as follows: dew point shall be verified for each weld and repair weld that is not inspected on the backside per 10.3.13 because of inaccessibility.
30.2.1.2 Stainless steel brushes used for cleaning shall be free of any
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