【国外标准】 Standard Test Methods of Sampling and Testing Pulps to be Used in the Manufacture of Electrical Insulation

8.1 The conductivity of the water extract of electrical grade pulp results from electrolytic impurities in the pulp potentially present as ionizable acids, bases, salts, or a combination of these. The presence of electrolytic impurities in electrical insulation is undesirable as they tend to lower insulation resistance and have corrosion-producing tendencies under conditions of applied potential. When comparing test data, note that the extract conductivity of pulps, especially those of high purity, changes with time after manufacturing in some instances. This test is useful for routine acceptance testing, the comparison of different pulps, and research work.61.1 These test methods cover the sampling and testing of cellulosic pulps for use in the manufacture of electrical insulating papers and boards or in the direct application of pulp fibers as insulation to electrical conductors.NOTE 1: Consider the significance of any one pulp property test method, as set forth herein, with discretion depending on the product made from the pulp.1.2 Sections on Reagents, Sampling, and Report are integral parts of each of the individual test methods that follow.1.3 Each test method is described as being a measure of either a bulk property of the pulp or a property of a handsheet formed from the pulp.1.3.1 Bulk characteristics determinable by these procedures appear in the following sections:Procedure Sections ASTMMethodReference TAPPIMethodReferenceAqueous Extract Conductivity 8 & 9 D202 . . .Aqueous Extract pH 10 & 11 D202 . . .Aqueous Extractable Acidity-     Alkalinity 12 & 13 D202 . . .Analysis of Ash for Cations by     Atomic Absorption Spectrophotometry 70 – 78 D1193 & D2576 . . .Ash Content 79 – 82 D202 T 413Dirt in Pulp 40 & 41 . . . T 213Fiber Analysis 23 & 24 D202 & D1030 . . .Fiber Length of Pulp 42 & 43 . . . T 232, T 233Freeness (Canadian Standard     Freeness) 53 & 54 . . . T 227Kappa Number/Permanganate     Number (Substances Oxidizable     by Permanganate) 27 & 28 . . . T 236, UM 251Laboratory Processing of Pulp     (Beater Method) 51 & 52 . . . T 200Moisture in Pulp 31 – 33 . . . T 210Neutral Aqueous Extractable  Hard-     ness in Pulp 16 – 22 D202, D1126, & D2576 . . .Pentosan Content of Pulp 29 & 30 . . . T 223Resistance of Pulp to Disintegration     (Standard RPG) 44 – 50 . . . T 239, UM 252Shive Count 34 – 39 . . . . . .Solvent-Soluble Matter in Pulp 25 & 26 D202 . . .Tensile Properties 65 – 69 D202 . . .Water-Extractable Chlorides 14 & 15 D202 . . .1.3.2 Handsheet characteristics determinable by these procedures appear in the following sections:Procedure Sections ASTMMethodReference TAPPIMethodReferenceAir Resistance (Porosity) 57 & 58 D202 T 205Apparent Density 63 & 64 D202 T 205Bursting Strength 59 & 60 D202 & D774/D774M T 205Folding Endurance (M.I.T.) 51 & 52 D202 & D2176 T 205Forming Handsheets for Physical     Tests of Pulp 55 & 56 . . . T 205Tensile Strength 65 & 66 D202 & D828 T 205NOTE 2: Methods for Ash, Silica, selected cations from Ash, Heat Stability, α, β, and γ Cellulose, Viscosity, Total Chlorine, Tear, and Dissipation Factor and Relative Permittivity, will be considered for addition as methods are developed.1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.