Document 0JzrqnkgkobxZd4X0yBVbo9Kb

CC: C. I. do Pont de Nemours & Company Wilmington, Delaware imm CNCiNCfRINO OCPARTMEMT H.D. Boyce J.C. Lang E.K. Mason A.P. Storm W.C. Weaver G.J. Adolph R.J. Ham J.R. Alle M.L. Jone W.H. Zane J.W. Farrell C.A. Parks W.M. Uhrich SEPTEMBER 25, 1967 ALL FIELD PROJECT MANAGERS (2) *1. M. SEAMANS, ALTAMIRA W. S. BRIGGS, BEAUMONT J. J. BELL, BREVARD A. D. DAT, CAPE FEAR C. S. ANDERSON, CHAMBERS WORKS W. S. FREE, CHATTANOOGA H. S. STANTON, JR., CIRCLEVILLE W. G. HARRIS, COLUMBUS SHOPS *P. W. TAILOR, JR., DINAMITA *W. J. POFFENBAUGH, JR.. D0ORRDDRREECC1HT *J. P. MULROONEY, DUCILO W. C. MANNEAR, AFPM, FLORENCE K. G. CAUGHMAN, JR., HOUSTON R. H. DAVIS, KINSTON R. G. STERNBERGER, LOUISVILLE J. E. EARLEY, MARTINSVILLE PRE-PROJECT PLANNERS (2) W. A. SAMANS, MAT PLANT *E. S. CLARK, JR., MATDOWN F. C. BAYLIS, MEMPHIS *W. B. CARTER, JR.,. MONTERREY H. F. REDMILE, OLD HICKORY W. S. LEWIN, PARLIN E. M. VASS, SABINE RIVER H. J. FEINEN, SAVANNAH RIVER E. K. DRAWDY,SEAFORD R. A. MINIARD, SPRUANCE *E. F. KC SPADDEN, UENTROP S. V. HINSON, VICTORIA C. D. BROWN, WASHINGTON WORKS S. KREWATCH, WAYNESBORO G. E. BARLOW, JR., WILMINGTON AREA R. C. REBER, CONSTRUCTION J. S. ADAM, CONSTRUCTION W. BLAKE, CONSTRUCTION .. . F_. W. MAY, CONSTRUCTION H. A. MOAK, CONSTRUCTION CONSTRUCTION DIVISION - INSULATION PRACTICES The insulation materials and installation methods used vary widely between sites, and, in some cases, vary within different areas on the same project. The use of certain materials and methods results in lower "in-place" cost of insulation. The attached listing is intended to re-emphasize some current cost saving material and installation information. It is expected that each site will review this list and immediately implement applicable items. One reminder, in most cases insulation is intended to last--maintenance free-for the life of the item being insulated, and the quality of workmanship must, be consistent with this philosophy. Your assistance and comments are solicited to help keep the Division ahead of the insulation industry. CONSTRUCTION DIVISION D. E. Sours, Div. Thermal Insulation Specialist ;i)ES:slg Attachment *For Information Only kttcm rmm setter uvma ... through chemistry c-Do oo o<n DU 051085 September 25, 1967 CONSTRUCTION DIVISION - INSULATION PRACTICES I. SPECIFICATIONS A. Standard Engineering Specifications 1. Have field supervision review Standard Specification SN100.S0A, "High Temperature Pipe Insulation." This specification replaces several others and represents the Standards Committee's recent thinking on the subject. Several require ments add to the costs and should be questioned on an individual basis (these are under review by the Standards Committee); other sections point out necessary items which should be, but are not always followed. See Sections 3.1.5, 3.1.7, 3.1.3, 4.1.1, 4.4.5, 5.1, 3.1, and Figures 7, 10 and 13. Also see new specifi cation SN213P. 2. The above comments- also apply to SN100.&5A, "High Temperature Equipment and Duct Insulation." 3. Tentative Specifications SN100.90A and 100.95A for cold insulation will soon be available in pink sheet form and should be obtained and reviewed by site supervision. B. Design Project Specifications These should be reviewed with Design and the Plant and updated to reflect current practices and include cost reduction, teletype and other approved changes; be sure that special plant requirements are included in these specifications. Route an updated copy of these specifications to all site engineers for their review and re-education. Special plant requirements which add extra costs should be reviewed for necessity with the Works Engineer; a factual cost comparison should be presented. II. INSULATION MATERIALS The least expensive purchased price materials often cost more to apply than premium materials, and since labor costs are increasing more rapidly than material prices, total installed costs of systems must be evaluated, rather than material prices of system components. DU 051086 DUP 1008006 -3 2. Sprayed materials for hot insulation, such as Monospray and Armaspray, have wide potential use where large areas must be covered. (Not approved at this time for use on stainless steel.) Sprayed (foamed in place) urethane has been used at a cost savings in the insulation of cold service equipment. 3. Preassembled stud weld pins, with cupped heads, which are spot welded through the insulation, eliminate sharp points and are a one-step rather than multi-step operation; a more uniform compression of the insulation is also obtained. AGM Industries, P. 0. Box 146, Canton, Mass., telephone A.C. 617, #23-4749, and others can provide more information. 4- Insulation blankets and bats SN200M can be utilized on many pieces of equipment where the current practice is to use block or cut lags. 5. On curved or cylindrical equipment and duct, use molded pipe insulation. Where molded insulation is not available in the thickness specified, it is usually less expensive to substitute thicker material than to cut lag strips of the thinner material. The next cost cutting alternate is to score board insulation and bend it around the equipment contours. Where the use of lag strips is the only possible method, they should be cut in the maximum width t same finished contour In some instances, where H&V duct is insulated externally, the insulation can be eliminated from the flanges, standing seams, etc. with a minimum heat transfer loss, thus eliminating the need to box around these projections. In other instances, the substitution of thicker than specified material will cover these projections and yield a net savings in installed cost. Insulation Finishes 1. For pipe insulation, factory applied finishes, roofing felts, and aluminum jackets prove less expensive than laminates, site applied canvas, "A" cloth, or reinforced mastics. DU 051087 DUP 1008007 5 B. Where site-fabricated fittings are used, they should be shop-fabricated using power saw, layout, jibs, and roll adhesive applicator. The work should be scheduled to assure largest volume of like items are fabricated at one time, and not on a piece-meal basis. Prefinish field installed fittings in the shop. Fabricated fittings should not receive a cement coat, our specifications require that only major voids or chips be filled to insure effective ness of the insulation. Precut large quantities of like size fabric pieces and other finish materials. C. Aluminum Jacket 1. Sites with large volume can justify the purchase of a mechanized shear for shop precutting. 2. Pregang punch the leading lap of jacket for^hot pipe insulation to eliminate the layout of individual holes for rivets. There is no need to layout and punch individual holes for screws. Mechanical screwdriver and approximate spacing eliminate these operations. Precut the bands to length for cold pipe insulation and equipment. 3. Hold jacket in place oh pipe and equipment with reusable expansion bands, or small pieces of aluninum-colored, pressure sensitive tape to be left in place, prior to fastening with bands or mechanically-applied screws or rivets. 4. Eliminate the extra fold on leading edge of the longitudinal seam lap. This is done to eliminate a sharp edge at the insistence of some plants. D. Use spray applied finishes on fittings, equipment and duct where mastics are required by the specifications. E. When large quantities of complicated assemblies such as special valves or pumps, spinning machines, etc. are required, fabricate one complete assembly, work out the problems and establish a production plan, then fabricate the assemblies on a production line basis. F. Do not coat insulation with cement--fill only voids which would impair the effectiveness of the insulation. D\J 0510^8 DUP 1008008 : gMMiaiiitiiiiElaaaiiaiaiiai 7- - D. Change double layer to single layer insulation. E. Eliminate insulation, eliminate finish on insulation, eliminate insulation on pipe and duct flanges. F. Gang insulation of nested items. G. Eliminate or minimize removable insulation. H. Use automatic aluminum jacket cutter. I. Raise permissible surface temperature from 140F. to 180F. This can reduce the thickness and eliminate some safety insulation. J. Eliminate reinforcing from mastic finishes on fittings and equipment not subject to unusual mechanical abuse. K. Use sodium silicate for fitting fabrication adhesive in lieu of fibrous adhesive 803. L. Eliminate complicated metal finish covers on equipment heads, substitute cloth and spray mastic finish painted with a hard durable finish material. M. Seal joints on above freezing cold insulation and eliminate separate vapor barrier. DU 051089 DUP 1008009