1、Designation:C108298(Reapproved 2014)Standard Specification forAsbestos-Cement Flat Sheet for Cooling Tower Fill1This standard is issued under the fixed designation C1082;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of las
2、t 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 three classes of flat asbestos-cement sheets for use as cooling tower fill.1.2 Specifically excluded
3、 from this specification areasbestos-cement products intended for use as tower partition-ing and casing materials,splash bars,water distributionconduits,and demisters.Also excluded are corrugated sheetsand splash bars used as cooling tower fill(heat exchangesurfaces)that are covered in Specification
4、 C1081.1.3 The values stated in the SI system are to be regarded asthe standard.The inch-pound units in parentheses are providedfor information only.1.4 WarningBreathing of asbestos dust is hazardous.Asbestos and asbestos products present demonstrated healthrisks for users and for those with whom th
5、ey come into contact.In addition to other precautions,when working with asbestos-cement products,minimize the dust that results.For informa-tion on the safe use of chrysotile asbestos,refer to“Safe Use ofChrysotile:A Manual on Preventive and Control Measures.”21.5 This standard does not purport to a
6、ddress 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:3C150 Specificat
7、ion for Portland CementC458 Test Method for Organic Fiber Content of Asbestos-Cement ProductsC459 Test Methods for Asbestos-Cement Flat ProductsC500 Test Methods for Asbestos-Cement PipeC1081 Specification for Asbestos-Cement Corrugated FillFor Use in Cooling TowersD2946 Terminology for Asbestos and
8、 AsbestosCementProducts3.Terminology3.1 Definitions:3.1.1 autoclaved product,nin asbestos cement,producttreated in a saturated steam atmosphere at between 689 to 1517kPa(110 to 220 psi)for at least 8 h,and that contain portlandcement as defined in Specification C150 together with silica inthe ratio
9、of 3:2 that can react to form calcium silicate reactionproducts.3.1.2 pressed product,nproduct pressed singly or instacks interlayered with templates,at a minimum pressure of12 MPa(1740 psi).3.1.3 textured product,nproduct with bas-relief motifsthat extend the external surface of a sheet sufficientl
10、y toincrease its heat transfer capacity by at least 10%underconditions of turbulent gravity flow.3.1.4 For additional definitions,refer to TerminologyD2946.4.Classification4.1 Type IFill consisting of autoclaved pressed sheetswithout textured surfaces that meet the requirements set forthin Table 1.4
11、.2 Type IIFill consisting of non-autoclaved pressedsheets without textured surfaces that meet requirements pre-sented in Table 1.4.3 Type IIIFill consisting of non-autoclaved,non-pressedsheets with textured surfaces,conforming to requirementsstated in Table 1.5.Test Methods5.1 Apparent Density:5.1.1
12、 This is determined by dividing the mass of a specimenafter drying to constant weight at 110C 6 10F,by the volumeof the specimen.5.2 Water AbsorptionIn accordance with Test MethodsC459.1This specification is under the jurisdiction of ASTM Committee C17 onFiber-Reinforced Cement Products and is the d
13、irect responsibility of SubcommitteeC17.03 on Asbestos-Cement Sheet Products and Accessories.Current edition approved Dec.1,2014.Published December 2014.Originallyapproved in 1990.Last previous edition approved in 2008 as C1082 98(2008).DOI:10.1520/C1082-98R14.2Available from The Asbestos Institute,
14、http:/ 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,W
15、est Conshohocken,PA 19428-2959.United States1 5.3 Flexural StrengthIn accordance with Test MethodsC459.5.4 Freeze-Thaw Resistance:5.4.1 The number of freeze-thaw cycles specified must notcause any apparent deterioration.Check for signs of delami-nation by means of a magnifying glass.Inspect the spec
16、imensfor the presence of invisible cracks by spraying isopropylalcohol from a hand spray bottle onto the specimen(hairlinecracks are revealed when the alcohol evaporates from thesurface).5.4.2 Each cycle shall consist of saturating the specimen bysubmerging in water at 30 6 2C(36 6 3F)during 2 hfollowed by rapid drainage and freezing to 20 6 2C(4 63F)during 10 6 0.2 h.The twice-daily cycle then repeatsstarting with the 2 h period of thawing and saturation in waterat 30C.5.5 Harkort Test:5.5.1 Th
