1、Designation: C1082 98 (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
2、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 three classes of flat asbestos-cement sheets for use as cooling tower fill.1.2 Specifical
3、ly excluded 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
4、 in Specification 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
5、those with whom they 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 standa
6、rd 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 AST
7、M Standards:3C150 Specification 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
8、Terminology for Asbestos and 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
9、 together with silica inthe ratio 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 e
10、xternal surface of a sheet sufficiently 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 m
11、eet the requirements set forthin Table 1.4.2 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 Tabl
12、e 1.5. Test Methods5.1 Apparent Density:5.1.1 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 o
13、nFiber-Reinforced Cement Products and is the direct 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: 10.15
14、20/C1082-98R14.2Available from The Asbestos Institute, 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.Copy
15、right ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.3 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
16、 of delami-nation by means of a magnifying glass. Inspect the specimensfor 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 t
17、he 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 The specimen is dried in an ov
18、en at 100 6 2C (2126 3F) for 2 6 0.2 h before rapidly dunking it in 10 6 0.1 kg(20 6 0.2 lb) of water at 20 6 2C (68 6 3F) for 10 6 0.2min. Then the specimen is examined for signs of deterioration.Check and inspect as in 5.4.1. If the specimen does not appeardeteriorated, return it to the oven for d
19、rying during 24 6 0.2 hat 110 6 2C (230 6 3F) before dunking again in the sameway.5.5.2 Subsequent drying cycles are all of 23 h 45 6 12 min.duration at the following temperatures:3rd drying 120 2C (258 3F)4th drying 130 2C (266 3F)5th drying 140 2C (284 3F)6th drying 150 2C (302 3F)7th drying 160 2
20、C (320 3F)5.5.3 Report the number of cycles sustained without dete-rioration.6. Inspection6.1 Inspection of the material shall be agreed upon by thepurchaser and the supplier as part of the purchase contract.7. Rejection and Rehearing7.1 Material that fails to conform to the requirements ofthese spe
21、cifications may be rejected. Rejection shall be re-ported to the producer or supplier promptly and in writing. Incase of dissatisfaction with the results of the tests, the produceror supplier may make claim for a rehearing.8. Certification8.1 When specified in the purchase order or contract, aproduc
22、ers or supplier certification shall be furnished to thepurchaser that the material was manufactured, sampled, tested,and inspected in accordance with this specification and hasbeen found to meet the requirements. When specified in thepurchase order or contract, a report of the test results shall bef
23、urnished.8.2 Upon request of the purchaser in the contract or orderthe certification of an independent third party indicatingconformance to the requirements of this specification may beaccepted instead of the manufacturers certification.9. Product Marking9.1 For Types I and II, print or stencil on e
24、ach piece, inalkali-resistant ink or paint, the identification either “Type I” or“Type 2.”10. Keywords10.1 asbestos; asbestos-cement; cooling tower fill; flat sheetTABLE 1 Manufacturing Composition and Performance RequirementsType No. I II IIIManufacturing Requirements:Autoclaved yes no noPressed ye
25、s yes noTextured no no yesThickness,mm 4.2 0.1 4.2 0.1 4.2 0.1(in.) (0.165 0.005) (0.165 0.005) (0.165 0.005)Composition Requirements:Silica passing through a 149 m sieve (No. 100) yes no noRatio, cement:silica 3:2 . Mineral diluents no no noCellulose no no noMaximum organic content per Test Method
26、C458, % 0.01 0.01 0.01Cement type; per Specification C150 1 IorV I,IIorVor ISO type 10 10 or 50 10, 20 or 50Performance Requirements:Minimum apparent density g/cm3(lb ft3) 1.6 (100) 1.6 (100) 1.4 (100)Maximum water absorption, % 25 25 30Average of lengthwise and crosswise orientations:Minimum flexur
27、al modulus of rupture:MPa (psi) 24.8 (3600) 24.8 (3600) 20.7 (3000)Minimum deflection (per Test Methods C459):mm 332(in.) (0.13) (0.13) (0.09)Minimum freeze-thaw, cycles 200 100 50Minimum Harkort test, cycles 7 5 3Maximum free lime, per Test Methods C500,% 1 6 7C1082 98 (2014)2ASTM International tak
28、es no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. 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 re
29、sponsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed 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 addres
30、sed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible 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 th
31、e 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). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 98 (2014)3
