1、Designation: C 450 02Standard Practice forFabrication of Thermal Insulating Fitting Covers for NPSPiping, and Vessel Lagging1This standard is issued under the fixed designation C 450; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、 the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice provides tables of dimensions of pre-formed insulation that may be used in fabricating cov
3、ers foruse on valves, ells, tees, flanges, and vessels in the pressurerange from 150 to 1500 psi (1 to 10 MPa). These tables, whichare part of this standard, are published separately as the ASTMRecommended Dimensional Standards for Fabrication of Ther-mal Insulation Fitting Covers for NPS Piping, an
4、d VesselLagging. The tables provide dimensions for use in formingpipe fitting covers for NPS pipe operating at high temperatureand low temperature. The tables also include dimensions foruse in forming thermal insulation into curved segments, andlagging, for application on vessels. This practice does
5、 not applyto reflective-type insulation.1.2 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
6、limitations prior to use.1.3 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are providedfor information purposes only.2. Referenced Documents2.1 ASTM Standards:C 585 Practice for Inner and Outer Diameters of RigidThermal Insulation for Nomina
7、l Sizes of Pipe and Tubing(NPS System)22.2 ASTM Adjuncts:ADJC0450 Recommended Dimensional Standards for Fab-rication of Thermal Insulating Fitting Covers for NPSPiping and Vessel Lagging33. Significance and Use3.1 This system of dimensions provides a guide for formingthermal insulation in advance of
8、 field application. Formingmay be done by cutting, grinding, milling, or molding, depend-ing upon the method most suitable for the thermal insulationbeing fabricated. It is equally applicable for all temperatureranges.4. Apparatus4.1 Thermal insulation can be formed into shapes by nu-merous methods.
9、 In general, insulations may be cut by circularor band saws, shaped by grinders or millers, or molded. Eachmethod has certain advantages and disadvantages, dependingupon the material to be formed, number of cuts required,material waste permissible, and quantity of fittings beingproduced. Adhesives a
10、nd fabrication cements can be appliedfrom dip pots, rollers, doctor blades, brush, or trowel, depend-ing upon the materials being used. For these reasons, althoughstandardized equipment may be devised for certain formingfunctions, no completely standardized equipment recommen-dation can be suggested
11、.5. Basis of Design5.1 All dimensions presented are based on the use of pipeinsulation manufactured to Practice C 585 and to the BasicDimensional Standards for Pipe Insulation as given in Tables 1and Tables 2 of the ASTM Recommended Dimensional Stan-dards for Prefabrication and Field Fabrication of
12、ThermalInsulation Fitting Covers for NPS Piping, and Vessel Lagging.35.2 The tables provide dimensions for insulation fittingcovers for installation on nominal pipe size (NPS) pipeoperating at high and low temperatures.5.3 Dimensions presented for cutting beveled blocks frompreformed thermal insulat
13、ion (lags) are based on blocks 6 in.(152 mm) wide by the thickness required.5.4 Dimensions given for flanged pairs, flanged fittings, andflanged valves do not allow for flange bolt removal. When boltremoval is required, the covering length over the flange shallbe increased as specified by the purcha
14、ser.6. Fabrication6.1 The main body of the insulation fitting may be cut fromstandard pipe size pipe covering of the proper size and samethickness tolerance as the pipe insulation.6.2 Where two insulations of different temperature ratings1This practice is under the jurisdiction of ASTM Committee C16
15、 on ThermalInsulation and is the direct responsibility of Subcommittee C16.20 on HomogeneousInorganic Thermal Insulations.Current edition approved July 10, 2002. Published November 2002. Originallypublished as C 450 60 T. Last previous edition C 450 99e1.2Annual Book of ASTM Standards, Vol 04.06.3Av
16、ailable at a nominal cost from ASTM Headquarters. Order Adjunct:ADJC0450.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.are required, each should be placed in its proper location in thefitting in double layer construction.6.3 Where
17、only one insulation is required, and it can beobtained in sufficient thickness, multiple layers as indicated arenot essential.6.4 Flat block, cut to proper curvature, may be used in placeof preformed pipe insulation. The user should be informedwhen supplying a fabricated product instead of a molded
18、orpreformed pipe insulation, there may result differences inthermal or mechanical performance characteristics of the endproduct.6.5 Any method of forming may be used if the resultingfitting conforms to inside and outside dimensions listed.6.6 Where the body of the flange cover extends overadjacent p
19、ipe insulation, the portion of the cover can be madeby using the pipe insulation as the body and adding an insertcollar. It can also be done by adding an insert or section,commonly called a “dutchman,” made of block.6.7 Valves manufactured by various companies for the samepressure and nominal pipe s
20、ize may not have like bonnetdimensions, nor height of bonnet flange above centerline ofvalve. Because of this, the valve insulation is designed to fit thelargest valve of a size, type, and pressure. In some instances,additional insulation may be required to fill or build up theinsulation for proper
21、fitting around the bonnet. In otherinstances it may be necessary to cut back insulation around thebonnet to provide access to the packing gland. Cutout for handwheel assembly and packing gland should be done at time ofapplication.7. Assembly and Tolerances7.1 All formed pieces should fit tightly tog
22、ether so that bothsides and length of the insulation joint can close within amaximum of116 in. (1.6 mm).7.2 Low-temperature pipe insulation fabricated from blockor board stock should contain no more than four cemented“through” joints per full section of insulation, excluding thehalf section mating p
23、lane.7.3 Finished pieces should be identified by tags, attachedstrip, etc. for ease of field installation.7.4 The inner and outer surface of vessel insulation sectionsshould be concentric with the outer surface. The deviation fromconcentricity should not exceed316 in. (5 mm).7.5 Cements to be used i
24、n the fabrication of fitting coversmust be specified for each insulation material by the manufac-turer of the insulating material.8. Insulation Fabrication Shop Requirements8.1 Insulation can be shop fabricated by several methods.Each method has certain advantages and disadvantages, de-pending on th
25、e number of pieces to be cut, cuts required,material properties, and resultant material waste. Fabricationmay be by sawing, grinding, routing, or combination thereof.Grinding and routing are generally limited to fabrication ofblock or board into threaded and socketwelded fittings, such aselbows and
26、tees. Selection of fabrication method shouldconsider any resulting reduction in material physical proper-ties.8.2 Equipment is commonly improvised, as grinders forfabrication of insulation are not commercially available. Themost essential piece of equipment is a band saw. Almost anyband saw that can
27、 be set at the proper blade speed and has aminimum cutting depth of 22 in. (559 mm) can be used.Essential details are as follows:8.2.1 Cutting Blade SpeedsThe proper speed of the bandsaw blade for cellular glass is approximately 1040 ft/min (317m/min). Calcium silicates and perlite silicate insulati
28、on may becut at a speed of 1040 ft/min (317 m/min), but somewhathigher speeds will also work satisfactorily.8.2.2 Blades for Cutting Cellular GlassBand saw bladesshould be 1 in. (25 mm) wide by 0.035 in. (0.9 mm) thick,flexible-back, three-pitch, raker-tooth blades. These bladeshave special teeth de
29、signated as “P.A.”8.2.3 Blades for Cutting Calcium Silicate or Perlite SilicateFiber InsulationBlades should be12 in. (13 mm) wide by0.035 in. (0.9 mm) thick, skip-tooth blades, 5 teeth/in.8.2.4 Abrasives for GrindersGrinders are sometimes usedto form insulation into various shapes. This can be done
30、 byhand or machine, by coating a tool (wood or steel) with anabrasive consisting of grit in glue. The recommended grit sizesare No. 16 and No. 24. The finer grit is used for power-drivenequipment, and the heavier grit for hand-powered equipment.9. Field Application Sequence9.1 Insulation coverings f
31、or welded or screwed fittingsshould be applied before the pipe insulation.9.2 Pipe insulation should be installed up to all flanges,flanged fittings, and flanged valves. Provide sufficient space forfuture bolt removal where required.9.3 Covers for flanges, flanged fittings, and flanged valvesshould
32、be installed so as to extend, not less than specifiedthickness, over adjacent pipe insulation or minimum 2 in.(50mm).9.4 Where required, junction of pipe insulation and flangedfittings covers can, by use of nonsetting cements, sealents orother methods, be used as an expansion or contraction joint.10
33、. Keywords10.1 thermal insulating materials; thermal insulatingmaterialsfabrication; thermal insulating materialsfittings;thermal insulating materialspipeC450022ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this sta
34、ndard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be revi
35、ewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsib
36、le technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).C450023
