1、Designation: C667 09 (Reapproved 2014)C667 17Standard Specification forPrefabricated Reflective Insulation Systems for Equipmentand Pipe Operating at Temperatures above Ambient Air1This standard is issued under the fixed designation C667; the number immediately following the designation indicates th
2、e 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 This specification covers the requirements for all
3、 metal prefabricated, reflective insulation systems for equipment and pipingoperating in air at temperatures above ambient. Typical applications are in nuclear power-generating plants and industrial plants.1.2 Reflective insulation is thermal insulation that reduces radiant heat transfer across spac
4、es by the use of surfaces of highreflectance and low emittance.1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information only and are not considered standard.1.4 This standard do
5、es not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.5 This
6、 international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT
7、) Committee.2. Referenced Documents2.1 ASTM Standards:2C168 Terminology Relating to Thermal InsulationC335 Test Method for Steady-State Heat Transfer Properties of Pipe InsulationC411 Test Method for Hot-Surface Performance of High-Temperature Thermal InsulationC835 Test Method for Total Hemispheric
8、al Emittance of Surfaces up to 1400CC854 Test Method for Resistance to External Loads on Metal Reflective Pipe Insulation (Withdrawn 1997)3C1045 Practice for Calculating Thermal Transmission Properties Under Steady-State ConditionsC1058 Practice for Selecting Temperatures for Evaluating and Reportin
9、g Thermal Properties of Thermal InsulationC1061 Test Method for Thermal Transmission Properties of Non-Homogeneous Insulation Panels Installed Vertically(Withdrawn 1995)3C1371 Test Method for Determination of Emittance of Materials Near Room Temperature Using Portable Emissometers3. Terminology3.1 D
10、efinitions:3.1.1 Terms relating to thermal insulation materials and testing are in accordance with Terminology C168.3.2 Definitions of Terms Specific to This Standard:3.2.1 convection stopsseals used to reduce convection losses.3.2.2 end supportsstructural members placed at the end of a unit of insu
11、lation and fastened to both the inner and outer case.3.2.2.1 Discussion1 This specification is under the jurisdiction of ASTM Committee C16 on Thermal Insulation and is the direct responsibility of Subcommittee C16.40 on InsulationSystems.Current edition approved Feb. 1, 2014Oct. 1, 2017. Published
12、March 2014November 2017. Originally approved in 1992. Last previous edition approved in 20092014 asC667C667 09 (2014).-09. DOI: 10.1520/C0667-09R14.10.1520/C0667-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Boo
13、k of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indicati
14、on of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be consi
15、dered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1The primary purpose of the end supports is to increase the structural integrity of the unit.3.2.3 inner casethe innermost sheet of the unit of insulation (clo
16、sest to the hot surface).3.2.3.1 DiscussionThe inner case may perform structural functions in addition to its thermal functions.3.2.4 insulation assemblyan assembly of insulation units arranged and secured together in a prescribed order that comprisesthe complete insulation for a vessel, pump, pipel
17、ine, or other component for a single design objective.3.2.5 insulation systema collection of insulation assemblies, that when secured together in a prescribed order, comprises thecomplete insulation for a vessel, pump, pipeline, or other component for a single design objective.3.2.6 lap strapsstrips
18、 that overlap a longitudinal or circumferential joint in the insulation which aligns adjacent insulationunits and may also serve to restrict air infiltration and convection losses and to shed external falling water.3.2.6.1 DiscussionThe lap straps may be integral with one piece of the outer case or
19、separate strips secured to it.3.2.7 outer casethe outermost sheet or the unit of insulation (farthest from the hot surface). It usually performs structuralfunctions in addition to its thermal functions.3.2.8 penetrationsopenings in a unit of insulation from the cold surface through to the hot surfac
20、e.3.2.9 reflective linersthose reflective sheets or foil interposed between the inner and outer case to reflect radiant energy, tominimize emission of radiant energy, and to restrict internal convection.3.2.10 thickness(see Fig. 1).3.2.11 unit of insulationa single structurally independent assembly
21、of inner case, outer case, reflective liners, and end supports(if required).3.3 Symbols:FIG. 1 Illustration of Terms Relating to Prefabricated Reflective Insulation SystemsC667 1723.3.1 The symbols used in this specification have the following significance:3.3.2 Ccconductance based on the area of in
22、sulation at the cold surface.4. Ordering Information4.1 Ordering information shall include the following:4.1.1 Service requirements including operating hot surface temperature, expected ambient temperatures, and ambient airvelocities,4.1.2 Expected service life and any special environmental exposure
23、s,4.1.3 Permitted average heat loss per unit of cold surface or as otherwise specified,thermal conductance based on hot pipetemperature and insulation cold surface temperature,4.1.4 Personnel exposure surface temperature limitations,4.1.5 Expected seismic, loading, and vibration exposures,4.1.6 Purc
24、hasers systems and equipment drawings,4.1.7 Limits, if any, on size, maximum thickness, weight, or number of insulation units requiring removal for inspection,4.1.8 Location of components or maintenance, or both, and systems requiring removal of units for inspections,4.1.9 Any unusual operating or t
25、est conditions, and4.1.10 Cleanliness level required.5. Materials and Manufacture5.1 Each insulation unit is a rigid, self-contained, prefabricated metal construction comprised of an inner casing and an outercasing, and if needed, one or more reflective liners supported and spaced so as to minimize
26、internal convection and conduction.These parts are arranged to form a durable rigid assembly with separated air spaces between the inner and outer casing and theindividual reflective liners.5.2 The reflective insulation described herein is limited to systems of insulating units, designed by the manu
27、facturer to fit theequipment or piping to be insulated, and engineered for the purchasers service requirements.5.3 All parts of reflective insulation units shall be made of metals that meet the thermal, physical, and chemical requirementsnot only of the insulation as a unit, but also as an assembly
28、of units forming the insulation system. The materials shall performtheir functions for the service life specified and be compatible with the environment in which they will be used.5.4 The stainless steel liners/foils shall be a minimum of 0.002 in. (0.05 mm) in thickness. Liners shall have an emitta
29、nce of0.25 or less when tested at 75 F (24 C) 75F (24C) in accordance with Test Method C1371. There shall be a minimum of threefoils per in. of insulation thickness. The options for the foils configuration are flat or patterned.6. Temperature Limitations6.1 Each insulation unit must effectively limi
30、t the flow of heat through the insulation by radiation, convection, and conduction.The reflective liners (also referred to as radiation shields or foils) are made of metals having low emittance and high reflectance.The emittance shall be tested in accordance with Test Method C835 or C1371. The numbe
31、r and spacing of the liners are determinedby the required limitation of heat flow.6.2 The temperature limits of various materials shall be based on the potential increase in radiant heat transfer across spacesdue to a reduction in reflectance and a corresponding increase in emittance resulting from
32、surface oxidation. Individual componentsof the insulation system operating at temperatures of 750F (400C) or higher shall not be made of aluminum or aluminum alloys.Components operating at 1200F (649C) or higher, shall be manufactured from Type 300 series austenitic stainless steel ormaterial with t
33、he same properties.6.3 A representative unit or assembly shall be tested in accordance with Test Method C411.7. Thermal Performance7.1 The purchase specification shall clearly indicate the permissible average rate of heat loss per unit area for each type ofsurface. The tests shall be in accordance w
34、ith Test Method C335 for pipes, or Test Method C1061 for flat surfaces, or a test methodagreed upon between the purchaser and manufacturer. Table 1 and Table 2 contain maximum tested values for apparent thermalconductivity. thermal conductance based on specific installation conditions identified in
35、notes A and B. Due to the fact that thethermal performance of metal reflective insulation depends on variables such as temperature, temperature difference, dimensions,emittance, and heat flow direction the manufacturer should be contacted for specific design recommendations regarding particularinsta
36、llation conditions. Butt joint heat losses shall be accounted for by including at least one butt joint within the metered area inthe thermal performance test. Practices C1045 and C1058 shall be used for determining and reporting thermal transmissionproperties.7.2 Due to the limitation of present con
37、figurations of reflective insulation, those being flat, cone and cylindrical, there can bea significant difference between the hot equipment surface area and the outer case area. Therefore, the thermal performance forC667 173equipment shall be referenced to the area of the outer case, unless otherwi
38、se specified. To be consistent, the outer case area shallalso be used for pipe, unless otherwise specified. For pipe, the pipe outside diameter shall be used thermal conductance at theinsulation cold surface is obtained by using 7.3.7.3 Thermal performance of pipe insulation per unit of cold surface
39、 area shall be obtained by multiplying transference (T) orconductance (C) as determined by Test MethodsMethod C335, where the outer surface area of the pipe is used to calculate C, byratio of the radii of the insulation test pipe outer surfaceradius (r20) and the test pipe insulation outer surface r
40、adius (ro2). Example:Cc5C 3ro/r2 (1)TABLE 1 PanelsApparent Thermal ConductivityAMeanTemperatureBtu in./h ft2(W/mk)184 (84.4) 0.369 (0.053)291 (143.8) 0.477 (0.069)398 (203.3) 0.657 (0.095)TABLE 1 PanelsThermal ConductanceAT0 F (C) T2 F (C) C (Btu/h ft2) C (W/m2K)298.8 (148.2) 91.6 (33.1) 0.073 0.412
41、513.0 (267.2) 112.6 (44.8) 0.097 0.548720.2 (382.3) 142.1 (61.2) 0.135 0.769AThe thermal transmission properties of metal reflective insulation depends ontemperature, temperature difference, dimensions, emittance, and heat flow direc-tion. The apparent thermal conductivity requirementsconductance da
42、ta specifiedin theTable 1 table are based on specimens tested as specified is based on a 4.625in. thick specimen installed with a 1 in. space between the heated test surface andhot surface of the test specimen using an Test Method C1061 hot box apparatuswith a 48 by 48 in. metering area that is orie
43、nted vertically (perpendicular to theground). T0 refers to the heat source surface temperature, T2in is the insulationcold surface temperature, and C is the Thermal Conductance of the test sample.The testing was performed in accordance with 7.1.TABLE 2 PipingApparent Thermal ConductivityATmean F Tme
44、anC k k (W/mk)Horizontal 181 82 0.506 0.073Horizontal 292 145 0.599 0.087Horizontal 411 211 0.741 0.107Vertical 181 83 0.625 0.091Vertical 294 146 0.755 0.109Vertical 416 213 0.886 0.128TABLE 2 PipingThermal ConductanceAApparatusOrientation T0 F (C) T2 F (C)C Btu/h ft2 F(W/m2K)C Btu/F h ft2(W/m2K)Ho
45、rizontal 296.8 (147.1) 100.5 (38.1) 0.186 (1.056) 0.112 (0.634)Horizontal 447.8 (231.0) 135.9 (57.7) 0.232 (1.317) 0.139 (0.791)Horizontal 702.3 (372.4) 174.1 (78.9) 0.298 (1.696) 0.179 (1.018)Vertical 294.0 (145.6) 108.7 (42.6) 0.219 (1.242) 0.131 (0.746)Vertical 494.9 (257.2) 151.3 (66.3) 0.282 (1
46、.600) 0.169 (0.961)Vertical 701.6 (372.0) 193.2 (89.6) 0.349 (1.982) 0.209 (1.190)AThe thermal transmission properties of metal reflective insulation depends ontemperature, temperature difference, dimensions, emittance, and heat flow direc-tion. The apparent thermal conductivity requirementsconducta
47、nce data specifiedin Table 2 is based on a 3 in. thick specimen with a 17.8 in. outer diameter installedon a 10 in. NPS Test Method C335the table are based on specimens tested asspecified in pipe test apparatus with metering length of 36 in. For purposes ofcalculating Cc, r0 = 5.40 in. and r2=8.99 i
48、n. The “Horizontal” apparatus orientationspecified in the table refers to the fact that the central axis of the test apparatuswas oriented parallel to the ground during testing. The “Vertical” apparatusorientation specified in the table refers to the fact that the central axis of the testapparatus w
49、as oriented perpendicular to the ground during testing. T0 refers to thepipe temperature, T2 is the cold insulation surface temperature, and C is theThermal Conductance of the test sample. The testing was performed in accor-dance with 7.1.C667 174where:Cc = conductance based on the area of the insulation (cold surface).7.4 Heat loss test conditions shall include consideration of insulation orientation (horizontal or vertical) and the insulation jointdesign.design as specified in 8.3.7.5 The specification shall not limit both heat loss th
