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DocuSign Envelope ID: 9826C043- 4C32- 49CD- A4CC- DC28ABAB7CE7 <br />SECTION 237690 - HANGERS AND SUPPORTS FOR HVAC PIPING AND EQUIPMENT <br />J. Install building attachments within concrete slabs or attach to structural steel. Install additional <br />attachments at concentrated loads, including valves, flanges, and strainers, NPS 2 -1/2 and larger <br />and at changes in direction of piping. Install concrete inserts before concrete is placed; fasten inserts <br />to forms and install reinforcing bars through openings at top of inserts. <br />K. Load Distribution: Install hangers and supports so piping live and dead loads and stresses from <br />movement will not be transmitted to connected equipment. <br />L. Pipe Slopes: Install hangers and supports to provide indicated pipe slopes and so maximum pipe <br />deflections allowed by ASME B31.1 (for power piping) and ASME B31.9 (for building services piping) <br />are not exceeded. <br />M. Insulated Piping: Comply with the following: <br />1. Attach clamps and spacers to piping. <br />a. Piping Operating above Ambient Air Temperature: Clamp may project through <br />insulation. <br />b. Piping Operating below Ambient Air Temperature: Use thermal- hanger shield insert <br />with clamp sized to match OD of insert. <br />C. Do not exceed pipe stress limits according to ASME B31.1 for power piping and <br />ASME B31.9 for building services piping. <br />2. Install MSS SP -58, Type 39, protection saddles if insulation without vapor barrier is indicated. <br />Fill interior voids with insulation that matches adjoining insulation. <br />3. Install MSS SP -58, Type 40, protective shields on cold piping with vapor barrier. Shields shall <br />span an arc of 180 degrees. <br />4. Shield Dimensions for Pipe: Not less than the following: <br />a. NPS 1/4 to NPS 3 -1/2: 12 inches long and 0.048 inch thick. <br />b. NPS 4: 12 inches long and 0.06 inch thick. <br />C. NPS 5 and NPS 6: 18 inches long and 0.06 inch thick. <br />d. NPS 8 to NPS 14: 24 inches long and 0.075 inch thick. <br />e. NPS 16 to NPS 24: 24 inches long and 0.105 inch thick. <br />5. Pipes NPS 8 and Larger: Include wood inserts. <br />6. Insert Material: Length at least as long as protective shield. <br />7. Thermal- Hanger Shields: Install with insulation same thickness as piping insulation. <br />3.3 EQUIPMENT SUPPORTS <br />A. Fabricate structural -steel stands to suspend equipment from structure overhead or to support <br />equipment above floor. <br />B. Grouting: Place grout under supports for equipment and make smooth bearing surface. <br />C. Provide lateral bracing, to prevent swaying, for equipment supports. <br />3.4 METAL FABRICATIONS <br />A. Cut, drill, and fit miscellaneous metal fabrications for trapeze pipe hangers and equipment supports. <br />B. Fit exposed connections together to form hairline joints. Field weld connections that cannot be shop <br />welded because of shipping size limitations. <br />C. Field Welding: Comply with AWS D1.1 procedures for shielded metal arc welding, appearance and <br />quality of welds, and methods used in correcting welding work, and with the following: <br />1. Use materials and methods that minimize distortion and develop strength and corrosion <br />resistance of base metals. <br />2. Obtain fusion without undercut or overlap. <br />3. Remove welding flux immediately. <br />4. Finish welds at exposed connections so no roughness shows after finishing and contours of <br />welded surfaces match adjacent contours. <br />Reece, Noland & McElrath, Inc. 237690-6 Orange County Board of Elections <br />Orange Co., NC 05/04/18 <br />