Attachment 2 - General Specification for ILA Design.pdf

This is a technical specification document from the Portsmouth Naval Shipyard (PNS) Corporate Lifting and Handling Manual, Volume III, Chapter 4, Appendix 6.1, establishing requirements for design and installation of Integral Lifting Attachments (ILAs) for general-purpose service equipment being manufactured for PNS.

The specification controls the design, documentation, and certification of ILAs, which are lifting attachments fabricated or formed as permanent parts of equipment or components to be lifted. ILAs include padeyes, holes cut in structures, threaded holes, and welded blocks. The document defines key terms including Unit (the item being lifted), PNS, Contractor (fabricating entity), Designer (qualified engineer), Base of Support, Qualified Engineer, and Working Load Limit (WLL). Any deviations must be approved in writing by PNS Lifting and Handling Department Technical Division (Code 710). A lifting plan with diagrams showing Unit weight, center of gravity, ILA details, and ILA locations must be provided by the Designer/Contractor and approved by PNS prior to fabrication. Padeyes are the preferred ILA type when practicable, and ILA materials must be steel or aluminum. ILAs shall be permanently marked with total Unit weight (2-inch high lettering), WLL for each ILA, test dates if applicable, and a minimum 8x10 inch placard displaying the lifting plan. ILAs must not be located below the Unit's center of gravity and must allow lifting using 2 to 4 ILAs in a level fashion with the Unit's Base of Support not exceeding 5 degrees from horizontal. ILAs must accommodate standard rigging equipment and be oriented to limit sling forces within 5 degrees of the padeye plane. The Designer must be a Qualified Engineer with calculations reviewed by a different Qualified Engineer, and all calculations must be approved by PNS prior to fabrication. ILAs must be designed per ASME BTH-1 standards with welds per AWS D1.1 specifications using a 5.0 safety factor on ultimate strength and 0.6 factor on shear stress. Welded connections require continuous welds around the exterior to prevent moisture entry. Threaded hole ILAs for indoor-use Units must have length at least 1.5 times the thread diameter for steel or 2.0 times for aluminum, using only standard UNC Class 2B threads. ILAs with capacity greater than 6,000 lbs. must undergo one-time 200 percent load testing at 200±5% of design capacity, maintained for at least 2 minutes, with written documentation provided to PNS at least 7 days prior to delivery.