Document DMm7gG15Rzjzzj813QVwYEY6d

. MINUTES of the .GOVERNMENT TECHNICAL k RESEARCH COMMITTEE MEETING- Marine Session NATIONAL INSULATION MANUFACTURERS ASSOCIATION Washington, D, C. December 4, 1962 The meeting was called to order by Mr. B. Tower with the following in attendance: B. Tower W, T. Irwin C. J. Hendrickson J. P, Sams A, E. Kincaid U. Smith , . Vfm P. Sinclair J. M. Barnhart Johns-Manville Sales Corp. Pittsburgh Plate Glass Co, M. H, Detrick Company Gustin-Bacon Mfg. Company Owens-Coming Fibergla-s Cprp. Baldwin-Ehret-Hill, Inc. Pittsburgh Coming Corp, NIMA P* R. Achenbach J. T. Nichols J. W. Ford R. L. Keller J. W. Wells J. W. West, Jr. R. E. Foote R. P. Seith National Bureau of Standards Maritime Administration U. S. Coast Guard U. S. Coast Guard U. S, Coast Guard Bureau of Ships Maritime Commission Bureau of Ships Bureau of Ships The questions was raised from the floor why there were two Sessions-, Maritime and Land, j This-was readily resolved by discussion of the difference in conditions of each service. Bob Seith, .Bureau of Ships informed the.members the purpose of the Military;;Standard ThermalInsulationRequirements for Machinery k Piping, fife incorporated all details ..concerning insulation requirements - such as materials,-thicknesses, applications and installation procedures which here-to-fore were covered in the General Specifications for Ships, Section S-39-2. The standard could be readily.revised and kept up to date, whereas 1 to 2 years were required to affect change in the General Specifications. The General Specifications also are being revised and will cover only insulation requirements of a general nature, such as definitions, basic applications, reason for insulating, etc. The MIL-Std., 769 will be referred to throughout the General Specifications. 2 The Members were asked to comment on the Standard, The following comment and recommendations were discussed: Page I_- Use or acceptance of brattice cloth Spec, MIL-C-788, Advant ages and disadvantages were covered. It was noted that cost could be substantially reduced by using brattice cloth in lieu of asbestos cloth. Further the deterioration of brattice cloth could be reduced by adequate coverage (paint, coatings, etc.). The paint, however, would crack on hot lines. It was decided that the use of brattice cloth for cold appli cations with a good vapor barrier would be acceptable. Specification MIL-I-23128, Refractory Fiber Insulation should be included in the list of specifications. Page 2 - Par, 4. 2, Sub-Par, (c) The accetpance of class (d) material for single layer applications up to 750h should be included. Further as this note permits the use of single layer material for high temperature applications (Table II indicates 1050F,, however, this will be modified to 12009F) expansion or thermal movement of the piping and components will be added to Sub-paragraph (c): "For single layer applications, suitable expansion joints, to permit thermal movement of the piping without opening of insulation joints, must be provided, " Page 3 - Par, 4, 3 It was noted that adhesives for securing elastomeric foamed plastic insulation, MIL-P-15280, were not included. Inasmuch as a specification for this material is not available, and each insulation manufacturer has his own recommended adhesive, it was suggested that a statement be included under "Installation" such as: compatable adhesives recommended by the insulation manufacturer shall be used, (Since the meetings, it was noted that the adhesive requirements are covered in MIL-P-15280, Par# 3, 7, the above statement is therefore not necessary). Page 5 - The proposal to add a "Note 2" under Table H indicating "Where thicknesses larger than 2 inches are specified, two layers may be used" was not considered necessary, Page 6 - Table IV A proposal was indicated, to reduce the required insulation tape thickness, for the temperature range 251 to 750, from 7/8 . to 3/4 inches, - It was agreed that the.difference in thickness was not -^significate, however, the commercially available thickness should be listed. The Chairman advised, that he would ascertain if the present listing of 7/8 inches is commercially available. If it is. not, BuShips will modify the thickness requirements to cover the nearest commercially available thickness. 3 Page 7 - Table VII The thickness requirements for molded cork (MIL-P-876) and Cellular Glass (HK-I-551) were questioned as they are the same, yet the conductivity of the material differs considerably. It was noted that these thicknesses were listed in previous specification, however, BuShips will determine if the difference in conductivity will permit a thickness reduction, (amounting to at least a commercial thick ness difference) for the lower conductivity material. Page 8 It was noted that preformed insulation fittings per MIL-I-22344 were not included in this standard. These fittings are presently approved by a BuShips instruction. They will be covered in a future modification to the standard after more experience has been gained concerning their application, * '** Page 10- Par, 6, 2 It was noted that the term "Antisweat Insulation" is not consistent with the terms used in Table I where "cold water and chilled water" are referenced. It was suggested that this inconsistency be eliminated, \ It was mentioned that one of the Shipyards were applying antisweat insula tion with staggered end joints. The reason for this application was ques tioned, BuShips indicated that the specification neither prohibit nor required staggered end joints for antisweat applications, only for refrig erant applications. This particular Shipyard probably realizes some advantanges from such an application, that other yards may not. Other items were discussed such as: The use of one standard for insulations rather than having a Navy (Ships), Maritime, Coast Guard, etc. It was advised that due to the different requirements of each activity it was necessary to have separated standards. Only a limited number of requirements would be-applicahle in all cases. On conclusion of the above, time permitted only a brief session of the - second item'of the Agenda, Cold Storage Insulation,. ' The Chairman briefly discussed SNAME Technical and Research Bulletin No, 4-4, Report on ShipYs Stores and Installed Cargo Refrigerated Boxes. The question was raised whether hold over temperature and stability of. refrigerated boxes could be maintained-with the use of low density types of thermal insulations, such as foamed-in-place or preformed foam; plastics. Mr, P. Achenbach, BuStandards stated that the frozen material ' inside a box is a factor in maintaining the. stable conditions based on. studies made by his Agency and Department of Agriculture, Reference was made to ASTM specification covering method of test for foamed-in-place polyurethane. Comment and suggestion were requested on other specifications used by the various government agencies* Adjournment There being no further business, the Meeting was adjourned. Respectfully submitted W, P. Sinclair