ASTM_C_1129_-_17.pdf

Designation:C112917Standard Practice forEstimation of Heat Savings by Adding Thermal Insulation toBare Valves and Flanges1This standard is issued under the fixed designation C1129;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 The mathematical methods included in this practiceprovide a calculational procedure for estimating heat loss orheat savings when thermal insulation is added to bare valvesand flanges.1.2 Questions of applicability to real systems should beresolved by qualified personnel familiar with insulation sys-tems design and analysis.1.3 Estimated accuracy is limited by the following:1.3.1 The range and quality of the physical property data forthe insulation materials and system,1.3.2 The accuracy of the methodology used in calculationof the bare valve and insulation surface areas,and the qualityof workmanship,fabrication,and installation.1.4 This procedure is considered applicable both forconventional-type insulation systems and for removable/reuseable covers.In both cases,for purposes of heat transfercalculations,the insulation system is assumed to be homog-enous.1.5 This practice does not intend to establish the criteriarequired in the design of the equipment over which thermalinsulation is used,nor does this practice establish or recom-mend the applicability of thermal insulation over all surfaces.1.6 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.7 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C168 Terminology Relating to Thermal InsulationC450 Practice for Fabrication of Thermal Insulating FittingCovers for NPS Piping,and Vessel LaggingC680 Practice for Estimate of the Heat Gain or Loss and theSurface Temperatures of Insulated Flat,Cylindrical,andSpherical Systems by Use of Computer ProgramsC1695 Specification for Fabrication of Flexible Removableand Reusable Blanket Insulation for Hot Service2.2 ASTM Adjuncts:3ADJC0450ARecommended Dimensional Standards forFabrication of Thermal Insulating Fitting Covers for NPSPiping and Vessel Lagging2.3 American National Standards Institute Standard:ANSI B16.5 Fittings,Flanges,and Valves43.Terminology3.1 DefinitionsFor definitions of terms used in thispractice,refer to Terminology C168.3.2 Symbols:1This practice is under the jurisdiction of ASTM Committee C16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.30 on ThermalMeasurement.Current edition approved March 1,2017.Published March 2017.Originallyapproved in 1989.Last previous edition approved in 2012 as C1129 12.DOI:10.1520/C1129-17.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from ASTM International Headquarters.Order Adjunct No.ADJADJC0450A.Original adjunct produced in 1976.Adjunct last revised in 2002.4Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 3.2.1 The following symbols are used in the development ofthe equations for this practice.Other symbols will be intro-duced and defined in the detailed description of the develop-ment.See Fig.1 and Fig.2.AB=outer surface area of the bare valve or flange(does notinclude the wheel and stem of the valve),ft2(m2).AI=surface area of the insulation cover over the valve orflange,ft2(m2).C=distance from the center-line axis of the pipe(to whichthe valve is attached)to the uppermost position of thevalve that is to be insulated(recommended to bebelow the gland seal),ft(m).DF=the valve flange and the bonnet flange outer diameter(assumed equal),ft(m).DP=the actual diameter of the pipe,ft(m).LV=overall length of the valve,flange to flange,ft(m).T=thickness of the valve flange and of the bonnet flange,ft(m).qB=time rate of heat loss per unit area from the bare valveor flange