Mechanical Insulation for Refrigeration Systems

Transcription

1 Mechanical Insulation for Refrigeration Systems INDUSTRIAL REFRIGERATION CONSORTIUM RESEARCH & TECHNOLOGY FORUM MAY 2-3, 2012 Peter Gauchel, President/CEO L&C Insulation Inc. Overview Current trends in insulation system components Challenges involved in insulation installation for industrial refrigeration systems Insulation system installation watch-outs Keys to maintaining effective insulation systems over their life 1

2 Vapor Barrier Mastics Mastic Description Permeability Childers CP-35 Water based, vapor retarder coating designed for all interior and exterior, low temperature and some dual temperature applications Fast drying and forms a tough, flexible dry film which retards the flow of vapor through an insulation system mils Childers CP-30 Effective vapor barrier coating for all low temperature applications Used as a barrier at the butt joints of pipe and block insulation where intermediate vapor stops are required It is not to be used in direct contact with polystyrene foams Childers CP-76 A balanced blend of butyl polymers specifically designed for permanent flexibility in low temperature, dual temperature, and high temperature insulation applications Used to vapor seal the joints of cellular glass and cellular plastic insulations (except polystyrene) An excellent water seal, vapor seal, and expansion joint material, and is suggested as a joint sealant for metal jacketing systems Mon Eco A low odor fire resistive vapor barrier coating designed for use on indoor or outdoor low temperature equipment Childers CP-11 A tough, durable, and fire-resistive water based mastic for most types of thermal insulation and finishing and insulating cements. A breathing coating (vapors under pressure will pass through it) Not a vapor barrier mastic Less than 0.02 perms at 0.02 inch film thickness perm tested in (1.3 mm) dry film at 100oF (38 C) and 90%RH.04 Perms at.020 film (.5mm) Childers CP-9 Not a vapor barrier mastic N/A Vimasco WC-7 Not a vapor barrier mastic. N/A N/A Jackets Jacket Description Permeability ASJ (All Service Jacket) White kraft reinforced foil vapor barrier that covers fiberglass pipe insulation and fiberglass duct board insulation Saran 540 A durable, flexible polyvinylidene chloride (PVDC) jacketing material for mechanical insulation systems in low to high vapor drive applications Saran 560 A durable, flexible polyvinylidene chloride (PVDC) jacketing material for mechanical insulation systems in medium to highest vapor drive applications Zero Perm A 3-ply composite membrane consisting of two 0.5 mil plies of polyester sandwiching one ply of 1.0 mil Aluminum Foil Provides maximum protection for all types of insulations used in below ambient, subfreezing and cryogenic applications on duct, pipe, or vessel systems Venture Clad Multilayered laminate coated with an aggressive cold weather acrylic pressure sensitive adhesive Superior resistance to weathering, mold, UV, and extreme environmental conditions 0.02 perms 0.02 perms 0.01 perms 0 perms 0 perms Stucco Embossed Aluminum Metal jacket used to protect pipe and duct insulation inside and outside facilities Provided in 0.016, 0.032, and thicknesses Not a vapor barrier 2

3 Standard Applications in Industry 3 thick insulation and less = 1 layer of insulation 3 ½ thick insulation and greater = double layer of insulation with staggered joints 1. Pipe 2. Insulation with longitudinal and circumferential joints staggered 3. Wire, tape or bands securing each layer in place 4. Jacket type (optional) *Vapor stop required for below ambient conditions Refrigeration Piping Lack of space for installation of specified insulation thickness which causes: Improper thicknesses to be used Breaks in vapor barrier Sealing of elbows, 45 s and Tee s Need to coat with a thick layer of mastic Using Saran Tape leaves too many fish mouths allowing air into the system 3

4 Vapor Stops and Vapor Dams The proper installation use every 15 Detail A Multiple Layer, Detail B Single Layer 1. Pipe 2. Insulation (single layer) 3. Vapor retarder jacketing 4. Outer layer of insulation (staggered joints) 5. Vapor mastic 6. Banding or tape on inner layer if required 7. Protective jacket (optional) 8. Appropriate vapor retarder or adhesive Expansion/Contraction Joints 1. Pipe 2. Layer of insulation (staggered joint) 3. Outer layer of insulation (staggered joint) 4. Jacketing bonded to outer layer on the left. This slides over the jacket on right forming a slip joint. 5. Pack contraction joints with flexible insulation material (at intervals specified) 6. Vapor stop (dam) mastic 7. Flexible vapor-retarder sealer 8. Jacket layer on right of slip joint 9. Vapor barrier jacket 4

5 Corrosion Under Insulation RG 2400 made by Polyguard Very expensive, but protects piping Aluminum Jacketing Installation Should always use stainless steel banding with wing seals Never allow staples Never allow screws This destroys the vapor barrier and the insulation system Hanger and/or support locations Questions? Never depend on the aluminum jacket to be a proper insulation support Galvanized or stainless steel saddles of 22 gauge or thicker should be installed outside of the aluminum jacketing Saddles should be secured with stainless steel banding to prevent them from falling out over time 5

6 Vessel Insulation for Refrigeration Systems 1 or 2 layers of Polystyrene should be used Proper vapor barrier jacket is needed Saran 560 and Zero Perm are best Aluminum or PVC jacket should be used to protect the insulation system These are not considered vapor barriers Detail A Contraction joint (typical) Detail B Double layer staggered joint construction Detail C Joint sealant application 1. Vessel surface 2. Contraction joint insulation 3. Contraction joint 4. Vapor stop (dam) 5. Insulation 6. Jacketing 7. Bands (Provide for contraction) 8. Head insulation shown secured with a floating ring of cable fastened to another ring of cable under head flange 9. Tank head jacket or finish 10. Vapor retarder mastic (if required) 11. Bottom insulation (High compressive strength, water, vapor resistance, and low coefficient of friction required) 12. Vapor retarder sealant (if required) 13. Vapor retarder jacket 14. Damp-proof course in between layers 15. Bottom course bedding sealant to prevent flood water ingress. (Bedding sealant must serve as a vapor retarder). 6

7 Questions? Contact Information Pete Gauchel, President/CEO L&C Insulation La Crosse, Eau Claire, Wausau, Appleton 7