1、Designation: D1118/D1118M 95 (Reapproved 2017)Standard Test Method forMagnetic Rating of Asbestos Fiber and Asbestos Textiles1This standard is issued under the fixed designation D1118/D1118M; the number immediately following the designation indicates theyear of original adoption or, in the case of r
2、evision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the procedure for the determi-nation of the magnetic rating of asbestos f
3、iber and asbestostextile products. This test method is used primarily for testingasbestos insulating materials.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem sh
4、all be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.3 WarningBreathing of asbestos dust is hazardous.Asbestos and asbestos products present demonstrated healthrisks for users and for those with whom they come into contact.In a
5、ddition to other precautions, when working with asbestos-cement products, minimize the dust that results. For informa-tion on the safe use of chrysoltile asbestos, refer to “Safe Useof Chrysotile Asbestos: A Manual on Preventive and ControlMeasures.”21.4 This standard does not purport to address all
6、 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. For specific safetyhazard, see .1.5 This international standard
7、 was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Refer
8、enced Documents2.1 ASTM Standards:3D123 Terminology Relating to TextilesD2100 Specification for Asbestos Textiles Used for Electri-cal Insulating PurposesD2590 Test Method for Sampling Chrysotile AsbestosD2946 Terminology for Asbestos and AsbestosCementProductsD2947 Test Method for Screen Analysis o
9、f Asbestos FibersD3879 Test Method for Sampling Amphibole Asbestos(Withdrawn 2009)4E11 Specification for Woven Wire Test Sieve Cloth and TestSieves2.2 ASTM Adjuncts:Metallic Analyzer Drawings53. Terminology3.1 For definitions of other textile terms used in this testmethod, refer to Terminology D123.
10、 For terms relating toasbestos, refer to Terminology D2946.3.2 Definitions:3.2.1 asbestos fiber, nThe hydrous magnesium silicateserpentine mineral designated as chrysotile and having theempirical formula Mg3Si2O5(OH)4.3.2.2 atmosphere for testing textiles, nfor asbestos, airmaintained at a relative
11、humidity of 50 6 2 % at 70 6 2F 216 1C.3.2.3 magnetic rating (MR), nan empirical value reflect-ing the effect of the magnetic particles, such as magnetic ironcompounds, in asbestos material as measured by a magneticeffect analyzer. It is not a quantitative measure of the magneticparticles in the mat
12、erial. Magnetic rating is affected by the1This test method is under the jurisdiction of ASTM Committee C17 onFiber-Reinforced Cement Products and is the direct responsibility of SubcommitteeC17.03 on Asbestos - Cement Sheet Products and Accessories.Current edition approved June 1, 2017. Published Ju
13、ly 2017. Originally approvedin 1950. Last previous edition approved in 2009 as D1118/D1118M 95(2009)1.DOI: 10.1520/D1118_D1118M-95R17.2Available from The Asbestos Institute, http:/ referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. Fo
14、r Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4The last approved version of this historical standard is referenced onwww.astm.org.5Available from ASTM International Headquarters. Order Adjunct No.ADJD1118. Original adjunct produced
15、 in 1986.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
16、 of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1quantity, concentration, particle size, shape, and orientation ofthe magnetic particles in the material.3.2.4 unit magnetic rating (1 MR), na calibrating standa
17、rdwith an MR of one is defined as containing 0.18 g of U.S.National Institute of Standards and Technology standardsample No. 29(a) or iron ore (magnetite) uniformly distributedover the space specified for a 10-g test specimen (19 mm 0.75in. diameter by 73 mm 2.875 in. long), by dispersion in amagnet
18、ically inert material. A10-g specimen has one unitmagnetic rating when it produces a magnetic effect equivalentto that of 0.18 g of standard magnetite as described above.Conversely, a 10-g specimen producing a magnetic effect suchthat the resulting induced current in the magnetic analyzergalvanomete
19、r is k times that of the 0.18 g of standard magnetiteas described above, would have a magnetic rating (MR) of k.4. Summary of Test Method4.1 The unknown electromagnetic effects of a sample ofasbestos-containing material is compared with those of areference standard in a magnetic analyzer. The induct
20、iveimbalance caused by the magnetic particles in the asbestossamples is amplified and measured with the magnetic analyzer.5. Significance and Use5.1 This test method for the determination of magneticrating is considered satisfactory for acceptance testing ofcommercial shipments of asbestos fibers, p
21、apers, felts, yarns,rovings, textile products, rigid sheet products, and granular orpowdered products.5.2 Magnetic rating is one of the measurements used fordetermining the suitability of an asbestos material for electricalinsulation.5.3 The electrical insulating properties of asbestos materialsvary
22、 inversely with the magnetic rating. Therefore, a lowmagnetic iron content is required for good electrical insulating.5.4 The types of asbestos textiles classified by magneticrating are described in Specification D2100.6. Apparatus6.1 Magnetic AnalyzerEither the Mapes type analyzer orthe Turner & Ne
23、wall5,6type analyzer may be used. Otheranalyzers using an inductance bridge and functioning on thesame principles may be used if agreed upon by the interestedparties.6.1.1 The Mapes type analyzer is described in Annex A1.6.1.2 The Turner & Newall6type analyzer is described inAnnex A2.NOTE 1The appar
24、atus and procedure described in this revision of TestMethod D1118 are preferred. The method and apparatus described inprevious issues of Test Method D1118 may be used if agreed upon by thepurchaser and the seller.6.1.3 Magnetic Analyzer Accessories, including specimentube, holder, spacer rod, and st
25、opper.6.1.4 Calibration Standards,6supplied by the vendor of themagnetic analyzer, or prepared as in A3.5.1 to A3.5.10.7. Hazards7.1 Warningsee .8. Sampling, Test Specimens, and Test Units8.1 Sampling:8.1.1 Chrysotile FiberSample chrysotile asbestos fiber inaccordance with Test Method D2590.8.1.2 Am
26、phibole FiberSample amphibole asbestos fiber inaccordance with Test Method D3879.8.1.3 Asbestos Textiles:8.1.3.1 Refer to appropriateASTM standards for the lot sizeof each type of material to be tested.8.1.3.2 Take sufficient samples at random from each lot toprepare specimens as directed in 8.2.8.1
27、.3.3 Refer to Section 11 for conditioning requirements.8.1.4 Papers, Scrims, Felts, and other NonwovenProductsRefer to appropriate ASTM standards for the lotsizes and conditioning requirements.8.2 Test SpecimensTest at least five specimens per sample.8.2.1 Asbestos Textiles:8.2.1.1 Cloth and LapSamp
28、le cloth or lap products bycutting across the warp strips 73 mm in width and of sufficientlength to give a mass of 15 6 0.1 g. Roll these specimens intoa scroll with an external diameter just less than 19 mm forinsertion into specimen holders.8.2.1.2 Roving, Wick, Rope, Yarn, Thread, Tubing, andTape
29、Cut enough pieces 73 mm in length to get a mass of 156 0.1 g. To adjust the mass precisely, when sample dimensionsallow it, cut the last portion of piece needed lengthwise. Ifdimensions are too small to cut lengthwise, as in the case of athread, cut across the length. Cord the pieces to form acylind
30、rical bundle with a diameter just less than 19 mm andwrap this with a sheet of paper 73 mm in width to facilitateintroduction into a specimen holder.8.2.2 Papers, Scrims, Nonwoven Products, and FeltsCutacross the machine direction into strips 73 mm in width andlong enough to give a mass of 15 6 0.1
31、g. Roll these specimensinto a scroll with an external diameter just less than 19 mm forinsertion into specimen holders.8.2.3 Granular or Powdered ProductsTo 15 6 0.1 gspecimens add sufficient nonmagnetic diluents, such as thosedescribed in A3.5.2, to increase the bulk enough to fill thespecimen hold
32、er cavity with moderate compaction. Load thediluted specimen into a sample holder in small pinches bymeans of a funnel, and depress to the required volume bypressing with the stopper or with a tamper. Remove the tamperand maintain the volume required by means of the stopper.8.2.4 Asbestos Fiber:8.2.
33、4.1 Take an approximately 2-kg 4-lb sample of asbes-tos as directed in Test Method D2590 for chrysotile or TestMethod D3879 for amphibole fiber.6The apparatus known as the “Turner and Newall Magnetic Analyzer” can bepurchased from Turner and Newall Ltd., Asbestos Fiber Laboratory, Trafford Park,Manc
34、hester 17, England. Detailed information on the preparation of calibrationstandards is available from ASTM International Headquarters, 100 Barr HarborDrive, W. Conshohocken, PA 19428. Request Adjunct ADJD1118.D1118/D1118M 95 (2017)28.2.4.2 Spread the sample of asbestos fiber on a smoothworking surfa
35、ce in layers to form a pile of uniform thicknessapproximately 10 mm 0.5 in. thick.8.2.4.3 Using tweezers, take five 3 6 0.1-g pinches in smallincrements, being careful that the total cross section of the pilefrom top to bottom is taken, including all particles that mayhave become segregated.8.2.4.4
36、Load the specimen into a holder by means of awide-mouthed funnel, in several pinches, and pack each pinchinto place with the spacer rod. Each pinch must include acomplete cross section of the specimen and the specimen mustnot be sprinkled into the funnel. Adjust the height of thespecimen with the sp
37、acer rod to 73 mm 278 in., and maintainthe height with a stopper.9. Preparation of Apparatus9.1 For Mapes type analyzers, energize the apparatus andpermit it to warm up for 20 min to become stable. Then balancethe secondary coils with the balancing coil until the deflectionof the indicating instrume
38、nt is a minimum at full sensitivity.9.2 For Turner & Newall6type analyzers, turn the sensitiv-ity switch S1A to the MR6 position (see Fig. A2.3), andenergize the apparatus with a 115-V, 60 Hz supply. Balance theapparatus by adjusting the balance screw to bring the galva-nometer deflection to zero. T
39、hrow the sensitivity switch to theMR1 position, and rebalance the apparatus, locking the bal-ancing screw in place.10. Calibration and Standardization10.1 For Mapes type analyzers, proceed as in A1.5 toA1.8.7 of Annex A1.10.2 For Turner & Newall6type analyzers, proceed as inA2.8 to A2.8.2 of Annex A
40、2.11. Conditioning11.1 Condition all samples (without preconditioning) for aminimum period of 4 h, or until the material shows noprogressive change in mass of more than 0.1 % after anexposure of an additional 0.5 h, in an atmosphere having arelative humidity of 50 6 2 % at 21 6 1C.12. Procedure12.1
41、Using Mapes Type Apparatus:12.1.1 Set the analyzer to give full-scale deflection with anMR6 standard, and insert the test specimen holder adjusting itsposition to produce maximum response.12.1.2 Note the galvanometer reading.12.1.3 If a voltage divider is fitted, and if the galvanometerreading is le
42、ss than half scale, then switch the divider to theappropriate scale, calibrate with the corresponding standard,and determine the magnetic rating of the test specimen underthese conditions.12.1.4 Repeat the above procedure for the other four speci-mens.12.2 Using Turner & Newall6Type Apparatus:12.2.1
43、 Start with the selector switch in position 10 toestablish the proper testing range and carefully insert theloaded specimen tube into the apparatus as far as it will go. Ifthe reading exceeds 3.0 on the upper set of graduations of themeter scale, record the indicated reading as the MR of thespecimen
44、 to the nearest 0.2 MR unit, otherwise proceed asfollows:12.2.1.1 When the reading in 12.2.1 is less than 3.0, turn theswitch to the 3-MR range. If the reading exceeds 1.0 on thelower set of graduations, record the indicated reading as theMR of the specimen to the nearest 0.1 MR unit.12.2.1.2 When t
45、he reading in 12.2.1.1 is less than 1.0, turnthe switch to 1-MR range. If the reading exceeds 0.3 on theupper set of graduations, record the indicated reading as theMR of the specimen to the nearest 0.02 MR unit.12.2.1.3 When the reading in 12.2.1.2 is less than 0.3, turnthe switch to 0.3-MR range a
46、nd record the indicated reading onthe lower set of graduations as the MR of the specimen to thenearest 0.01 MR unit.12.2.2 After obtaining a reading in the above manner,remove the specimen tube, verify the zero point, and recheckthe calibration using the appropriate magnetic calibrationstandard for
47、that range. Reinsert the specimen tube and verifythe MR value of the specimen.12.2.3 Proceed as directed in 12.2.1 and 12.2.2 on theremaining specimens.NOTE 2The procedure here described is applicable only under thoseconditions wherein the magnetic particles being tested exhibit no direc-tional prop
48、erties or when the particle distribution is such as to give theultimate in random orientation. The magnetic particles present in chryso-tile asbestos, however, are most frequently needle-like or acicular, and assuch exhibit directional properties with regard to magnetic permeability.Therefore, there
49、 must be an understanding as to the extent of the fibrouscharacteristics and the grain size distribution of the magnetic particlespresent in the sample under test if a proper evaluation of the resultingmagnetic rating is to be truly factual. In view of the fibrous characteristicsof the magnetic particles and the resultant directional magnetic properties,the method of sample preparation and the placement of the sample in thesample holder must be carefully pursued in an endeavor to obtain a tes
