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Experience with Stainless Steel Piping in Ammonia Refrigeration Systems

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Experience with Stainless Steel Piping in Ammonia Refrigeration Systems Experience with Stainless Steel Piping in Ammonia Refrigeration Systems Dave Schaefer, PE, LEED® AP Dave is a LEED® Accredited Professional experienced in managing all aspects of industrial refrigeration and HVAC projects including engineering, design and estimating. Dave has managed projects at Ace Banking, Hillshire Farms, Bay Ship, Marinette Marine, Ocean Spray, and has performed various energy conservation audits and installations. Dave has over 30 years of engineering experience. Dave is a licensed engineer in Wisconsin, Ohio, Michigan, Idaho, Nevada, Massachusetts, New Jersey, Oregon, South Carolina, Washington, Missouri, California, Arizona and Pennsylvania. Dave also holds a license for refrigeration contracting in Nevada, Michigan, New Jersey, Oregon, South Carolina, Washington and Florida and is a certified hazard analysis team leader. PROFESSIONAL MEMBERSHIPS EDUCATION IIAR B.S., Biological Systems Engineering, Board of Directors University of Wisconsin, Madison Standards Committee Chairman – IIAR-2: Standard for Safe Design of Unilever Project Engineering, Closed-Circuit Ammonia Refrigeration Systems Manchester, England Chairman – IIAR Task Group charged with International Mechanical Code Changes Unilever International Management RETA Training, Amsterdam NCEES ASHRAE LEED® Accredited Professional Refrigeration Chair and Board of Governors Why? . Lower MI NDT Costs . Can be used at lower temperatures . Lower Weight . Do not need corrosion inhibitor . More available than SA 333 for low temperatures . More resistant to cycling temperatures . Do not have to paint Where Stainless Steel is Used? . All Piping . Entire Plants . Skids Where Stainless Steel is Used? Sensitive Receptors Where Stainless Steel is Used? . Spool Piping . Valve Gang Tail Pieces . Transition from SS to CS requires use of 309 / 309L filler material Where Stainless Steel is Used? . All Process Spiral Freezers . Wash Down Areas . Process and Production Areas Where Stainless Steel is Used? . Transfer Vessels Where Stainless Steel is Used? . When Weight is an issue 2008 IIAR-2 add B 10.2.3 The use of 1/2 inch and smaller pipe is not recommended. Where the use of 1/2 inch and 10.2.2 Minimum Pipe Wall Thickness smaller 10.2.2.1 Carbon steel, welded. pipe is required in the engineering design, it shall be a. 1- 1⁄2 inch and smaller — schedule 80 adequately supported and/or protected to prevent b. 2 inch through 6 inch — schedule 40 damage. c. 8 inch through 12 inch — schedule 20 201X PR#5 d. 14 inch and larger — schedule 10. 10.2.2.2 Carbon steel, threaded, shall be 13.2.2 Minimum Pipe Wall Thickness. Minimum schedule 80 for all sizes. pipe wall thickness shall be based on the properties 10.2.2.3 Stainless steel, welded. of the selected pipe material and the design working a. 3⁄4 inch through 11⁄2 inch — schedule 40 pressure, and shall comply with the requirements of b. 2 inch and larger — schedule 10. ASME B31.5. 10.2.2.4 Stainless steel, threaded, shall be EXCEPTIONS: schedule 80 for all sizes. 1. Carbon and stainless steel threaded pipe shall be EXCEPTION: minimum Schedule 80 for all sizes. Stainless steel tubing and associated 2. Carbon steel pipe 1-1⁄2 inch and smaller shall be compression fittings. minimum Schedule 80. EXAMPLE: Used for compressor 3. Stainless steel pipe 1-1⁄2 inch and smaller shall be lubrication lines; small bore pressure minimum Schedule 40. sensing lines; hydrostatic relief lines; etc. Where Stainless Steel is Used? Plate & Frame Falling Film Heat Exchanger Where Stainless Steel is Used? Condensers . Long Product Life . Self Passivating stainless steel provides minimum product life twice that of galvanized steel . Reduced expense for substructure to be . 50% less operating provided weight on-site by customer . Reduced installation Labor . Simplified rigging . Lower Operating Costs . Water Savings . Less Chemical Usage Where Stainless Steel is Used? . Equipment . Recirculators Where Stainless Steel is Used? . Oil Pots Where Stainless Steel is Used? . Remote Sumps Where Stainless Steel is Used? . Relief Valves Where Stainless Steel is Used? . Valves Where Stainless Steel is Used? . Purgers Where Stainless Steel is Used? . Roof Stands . Roof / Building Penetrations . Piping Supports . Hangers & Hanger Rods Challenges . Cost Fluctuations Challenges . Outdoor Installations Challenges & techniques “Trace Element Large gas lens creates Certified” Chloride laminar flow of shielding Free Markers in adverse conditions Weld Dams – Sized Temperature according to pipe Sticks diameter Summary . Cost Short Term Summary . Cost Long Term . Lower Maintenance Costs . Lower Leak Potential . Weight . Techniques . Reliability . Safety . Liability .
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