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3.1 This test method defines the thermal expansion of porcelain enamel and glaze frits by the interferometric method. This determination is critical in avoiding crazing (cracking) of these glass coatings due to mismatching of the thermal expansion between the coating and substrate materials.1.1 This test method covers the interferometric determination of linear thermal expansion of premelted frits (porcelain enamel and glaze) and fired ceramic whiteware materials at temperatures lower than 1000 °C (1830 °F).1.2 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.1.3 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.

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5.1 The major objective of this practice is to provide a common reference document for both applicants and certification authorities on the accepted practices for accomplishing package thermal qualification. Details and methods for accomplishing qualification are described in this document in more specific detail than available in the regulations. Methods that have been shown by experience to lead to successful qualification are emphasized. Possible problems and pitfalls that lead to unsatisfactory results are also described.5.2 The work described in this standard practice shall be done under a quality assurance program that is accepted by the regulatory authority that certifies the package for use. For packages certified in the United States, 10 CFR 71 Subpart H shall be used as the basis for the quality assurance (QA) program, while for international certification, ISO 9000 usually defines the appropriate program. The quality assurance program shall be in place and functioning prior to the initiation of any physical or analytical testing activities and prior to submittal of any information to the certifying authority.1.1 This practice defines detailed methods for thermal qualification of “Type B” radioactive materials packages under Title 10, Code of Federal Regulations, Part 71 (10CFR71) in the United States or, under International Atomic Energy Agency Regulation SSR-6. Under these regulations, packages transporting what are designated to be Type B quantities of radioactive material shall be demonstrated to be capable of withstanding a sequence of hypothetical accidents without significant release of contents.1.2 The unit system (SI metric or English) used for thermal qualification shall be agreed upon prior to submission of information to the certification authority. If SI units are to be standard, then use IEEE/ASTM SI-10. Additional units given in parentheses are for information purposes only.1.3 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.1.4 This standard is used to measure and describe the response of materials, products, or assemblies to heat and flame under controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products, or assemblies under actual fire conditions.1.5 Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting these tests.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.

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This specification covers zinc and zinc alloy wire used to deposit zinc coatings by thermal spraying (metallizing) for the corrosion protection of steel and iron. Zinc and zinc alloy wire provided under this specification is intended for use in oxy-fuel and electric arc thermal spraying equipment. The zinc used to manufacture the wire shall conform to the requirements for high grade zinc (Z15001) or special high grade zinc (Z13001). The wire shall conform to the chemical requirements for aluminum, cadmium, copper, iron, lead, tin, antimony, silver, bismuth, arsenic, nickel, magnesium, molybdenum, titanium, and zinc. The wire shall be clean and free of corrosion, adhering foreign material, scale, seams, nicks, burrs, bends or kinks which would interfere with the operation of thermal spraying equipment. The wire shall uncoil readily and shall be a continuous length per spool, coil, or drum. Splices or welds are permitted, provided that they do not interfere with the thermal spray equipment or coating process.1.1 This specification covers zinc and zinc alloy wire used to deposit zinc coatings by thermal spraying (metallizing) for the corrosion protection of steel and iron. Zinc and zinc alloy wire provided under this specification is intended for use in oxy-fuel and electric arc thermal spraying equipment. Additional zinc alloy compositions used in thermal spraying primarily for electronic applications are found in Specification B943.1.2 Zinc alloy wire compositions used in thermal spraying primarily for electronic applications are found in Specification B943.1.3 Zinc alloy wire compositions used as solders are found in Specification B907.1.4 The values stated in SI units are to be regarded as the standard. The values 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 become familiar with all hazards including those identified in the appropriate Material Safety Data Sheet (MSDS) for this product/material as provided by the manufacturer, 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.

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5.1 Residue in LPG is a contaminant that can lead to operational problems in some end use applications. Engines, micro-turbines, fuel cells and other equipment may be sensitive to residue levels as low as 10 mg/kg.5.2 Contamination of LPG can occur during production, transport, delivery, storage and use. A qualitative indication of the contaminants can help track down the source of the contamination from manufacture, through the distribution system, and to the end user.5.3 This test method is designed to provide a lower detection limit, wider dynamic range, and better accuracy than gravimetric methods like Test Method D2158.5.4 This test method can be performed with little or no discharge of LPG vapors, compared to Test Method D2158 which requires evaporation of 100 mL of sample per test.5.5 Sampling for residue in LPG using sorbent tubes can be performed in the field, and the sorbent tubes sent to a laboratory for analysis. This saves significant costs in shipping (weight of tube is approximately 10 grams), and is much safer and easier than transporting LPG cylinders.5.6 This test method determines total residues from C6 to C40, compared to a thermal gravimetric residue method such as Test Method D2158 which heat the residue to 38°C, resulting in a lower recovery due to loss of lighter residue components.5.7 If there is a need to decrease the detection limit of residue or individual compounds of interest below 10 µg/g, the procedures in this test method can be modified to achieve 50 times enhanced detection limit, or 0.2 µg/g.1.1 This test method covers the determination of residue in LPG by automated thermal desorption/gas chromatography (ATD/GC) using flame ionization detection (FID).1.2 The quantitation of residue covers a component boiling point range from 69°C to 522°C, equivalent to the boiling points of C6 through C40 n-paraffins.1.2.1 The boiling range covers possible LPG contaminants such as gasoline, diesel fuel, phthalates and compressor oil. Qualitative information on the nature of the residue can be obtained from this test method.1.2.2 Materials insoluble in LPG and components which do not elute from the gas chromatograph or which have no response in a flame ionization detector are not determined.1.2.3 The reporting limit (or limit of quantitation) for total residue is 6.7 µg/g.1.2.4 The dynamic range of residue quantitation is 6.7 to 3300 µg/g.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 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 and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 Results from this accelerated corrosion test shall not be considered as an indicator of the useful life of the metal equipment. Many factors need consideration for applicability to specific circumstances. Refer to Guide C1696 and Practice G31 for additional information.5.2 Corrosion associated with insulation is an important concern for insulation manufacturers, specification writers, designers, contractors, users and operators of the equipment. Some material specifications contain test methods (or reference test methods contained in other material specifications), for use in evaluating the insulation with regard to the corrosion of steel, copper, and aluminum. In some cases these tests are not applicable or effective and have not been evaluated for precision and bias.5.3 A properly selected, installed, and maintained insulation system will reduce the corrosion that often occurs on an un-insulated structure. However, when the protective weather-resistant covering of an insulation system fails, the conditions for the aqueous environment necessary for corrosion under insulation (CUI) often develop. It is possible the insulation contains, collects, or concentrates corrosive agents, or a combination thereof, often found in industrial and coastal environments. If water is not present, these electrolytes cannot migrate to the metal surface. The electrochemical reaction resulting in the aqueous corrosion of metal surfaces cannot take place in the absence of water and electrolytes. Additional environmental factors contributing to increased corrosion rates are oxygen, and elevated-temperature (near boiling point).5.4 Chlorides and other corrosive ions are common to many environments. The primary corrosion preventative is to protect insulation and metal from contamination and moisture. Insulation covers, jackets, and metal coating of various kinds are often used to prevent water infiltration and contact with the metal.5.5 This procedure can be used to evaluate all types of thermal insulation and fireproofing materials (industrial, commercial, residential, cryogenic, fire-resistive, insulating cement) manufactured using inorganic or organic materials, faced or unfaced, for which a filtered extraction solution can be obtained.5.6 This procedure can be used with all metal types for which a coupon can be prepared such as mild steel, stainless steel, copper, or aluminum. Other metals (copper, aluminum) will need different times, reference solutions and cleaning practices. It shall not be interpreted that the steel procedures work for everything. When procedures are developed for other metals they will be balloted for inclusion in the document.5.7 This procedure can also be applicable to insulation accessories including jacketing, covers, adhesives, cements, and binders associated with insulation and insulation products.5.8 Heat treatment of the insulation (as recommended by the manufacturer up to the maximum potential exposure temperature) can be used to simulate possible conditions of use.5.9 Adhesives can be tested by first drying followed by water extraction or by applying a known quantity of the test adhesive to a test piece of insulation and then extracting.5.10 Insulating cements can be tested by casting a slab, drying, and extracting or by using the uncured insulating cement powder for extraction.5.11 Reference tests prepared with various concentrations of solutions that are conducive to the corrosion of the tested metal serve as comparative criteria. Solutions containing chloride, sodium hydroxide, various acids (sulfuric, hydrochloric, nitric, and citric acid), as well as “blank” tests using only de-ionized water and tap water are used.5.12 Research can be done on insulation that has been specially formulated to inhibit corrosion in the presence of corrosive ions through modifications in basic composition or incorporation of certain chemical additives. Corrosive ions can also be added to the insulation extraction solutions to determine the effectiveness of any inhibitors present.5.13 Protective surface treatments and coatings of different types and thickness can be applied to the metal coupons and compared using various corrosive liquids.5.14 Several sets of tests are recommended because of the number of factors that affect corrosion. An average of the tests and the standard deviation between the test results are used on the data. Much of the corrosion literature recommends a minimum of three specimens for every test. Consult Guide G16 for additional statistical methods to apply to the corrosion data.1.1 This practice covers procedures for a quantitative accelerated laboratory evaluation of the influence of extraction solutions containing ions leached from thermal insulation on the aqueous corrosion of metals. The primary intent of the practice is for use with thermal insulation and associated materials that contribute to, or alternatively inhibit, the aqueous corrosion of different types and grades of metals due to soluble ions that are leached by water from within the insulation. The quantitative evaluation criteria are Mass Loss Corrosion Rate (MLCR) expressed in mils per year determined from the weight loss due to corrosion of exposed metal coupons after they are cleaned.1.2 This practice cannot cover all possible field conditions that contribute to aqueous corrosion. The intent is to provide an accelerated means to obtain a non-subjective numeric value for judging the potential contribution to the corrosion of metals that can come from ions contained in thermal insulation materials or other experimental solutions. The calculated numeric value is the mass loss corrosion rate. This calculation is based on general corrosion spread equally over the test duration and the exposed area of the experimental cells created for the test. Corrosion found in field situations and this accelerated test also involves pitting and edge effects and the rate changes over time.1.3 The insulation extraction solutions prepared for use in the test can be altered by the addition of corrosive ions to the solutions to simulate contamination from an external source. Ions expected to provide corrosion inhibition can be added to investigate their inhibitory effect.1.4 Prepared laboratory ionic solutions are used as reference solutions and controls, to provide a means of calibration and comparison.21.5 Other liquids can be tested for their potential corrosiveness including cooling tower water, boiler feed, and chemical stocks. Added chemical inhibitors or protective coatings applied to the metal can also be evaluated using the general guidelines of the practice.1.6 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.7 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.1.8 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.

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1.1 This test method covers the procedure for determining the relative resistance of fired fireclay and high alumina refractories to thermal shock conditions resulting from specified heating and cooling cycles. The equipment specified is based on test units currently in use at several industrial laboratories. 1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are provided for information purposes only. 1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 It is possible that insulating blocks or boards that are not true or square will not fit properly. It is possible that extra labor will be required to obtain proper fit and that this could affect the product performance as well as the appearance of the finished installation.4.2 This test method provides terminology and describes locations for obtaining consistent measurements of trueness and squareness of blocks and boards.1.1 This test method covers locations for measuring the trueness and squareness of rigid block/board thermal insulation. This test method does not purport to address the variability in board thickness. Thickness is addressed in other ASTM standards.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 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.1.4 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.

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ASTM C552-22 Standard Specification for Cellular Glass Thermal Insulation Active 发布日期 :  1970-01-01 实施日期 : 

This specification covers the composition, sizes, dimensions, and physical properties of cellular glass thermal insulation. The material shall consist of a glass composition that has been foamed or cellulated under molten conditions, annealed, and set to form a rigid noncombustible material with hermetically sealed cells. The materials shall also be trimmed into rectangular or tapered blocks of standard dimensions. All specimens shall also comply with with qualification requirements such as compressive strength, flexural strength, water absorption, water vapor permeability, thermal conductivity, hot-surface performance, thermal conductivity and surface burning characteristics. These properties shall be determined in accordance with test methods specified herein.1.1 This specification covers the composition, sizes, dimensions, and physical properties of cellular glass thermal insulation intended for use on commercial or industrial systems with operating temperatures between −450 and 800°F (−268 and 427°C). It is possible that special fabrication or techniques for pipe insulation, or both, will be required for application in the temperature range from 250 to 800°F (121 to 427°C). Contact the manufacturer for recommendations regarding fabrication and application procedures for use in this temperature range. For specific applications, the actual temperature limits shall be agreed upon between the manufacturer and the purchaser.1.2 This specification does not cover cellular glass insulation used for building envelope applications. For cellular glass insulation used in building applications refer to Specification C1902.1.3 Cellular glass insulation has the potential to exhibit stress cracks if the rate of temperature change exceeds 200°F (112°C) per hour.1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.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.

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1.1 This standard is the compilation of definition of technical terms related to conditioning, chemical, and thermal properties in textiles. Terms that are generally understood or adequately defined in other readily available sources are not included. 1.2 For other ASTM defined conditioning terms, refer to Terminology E41. For other terms associated with textiles, refer to Terminology D123, Relating to Textiles.

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5.1 This test method measures the tendency of automotive manual transmission and final drive lubricants to deteriorate under high-temperature conditions, resulting in thick oil, sludge, carbon and varnish deposits, and the formation of corrosive products. This deterioration can lead to serious equipment performance problems, including, in particular, seal failures due to deposit formation at the shaft-seal interface. This test method is used to screen lubricants for problematic additives and base oils with regard to these tendencies.5.2 This test method is used or referred to in the following documents:5.2.1 American Petroleum Institute (API) Publication 1560-Lubricant Service Designations for Automotive Manual Transmissions, Manual Transaxles, and Axles,75.2.2 STP-512A–Laboratory Performance Tests for Automotive Gear Lubricants Intended for API GL-5 Service,85.2.3 SAE J308-Information Report on Axle and Manual Transmission Lubricants,9 and5.2.4 U.S. Military Specification MIL-L-2105D.1.1 This test method is commonly referred to as the L-60-1 test.2 It covers the oil-thickening, insolubles-formation, and deposit-formation characteristics of automotive manual transmission and final drive axle lubricating oils when subjected to high-temperature oxidizing conditions.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.2.1 Exceptions—The values stated in SI units for catalyst mass loss, oil mass and volume, alternator output, and air flow are to be regarded as standard.1.2.2 SI units are provided for all parameters except where there is no direct equivalent such as the units for screw threads, or where there is a sole source supply equipment specification.1.3 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. Specific warning information is given in Sections 7 and 8 and Annex A7.1.4 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.

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5.1 The data from this guide seldom, if ever, directly simulate thermal and pressure events in the processing, storage, and shipping of chemicals. However, the data obtained from this guide may be used, with suitable precautions, to predict the thermal and pressure hazards associated with processing, storage, and shipping of a chemical or mixture of chemicals after appropriate scaling of the data. This has been addressed in the literature (1-4) but is beyond the scope of this guide.5.2 This guide is suitable, under the proper conditions, for the investigation of the effects of catalyst, inhibitors, initiators, reaction atmospheres, materials of construction, or, if available, agitation (see 6.1.2).5.3 Interpretation of the time-temperature or time-pressure data may be possible for relatively simple systems through the use of suitable temperature-dependent kinetic theories such as the Arrhenius and Absolute Reaction Rate theories (5, 6).1.1 This guide covers suggested procedures for the operation of a calorimetric device designed to obtain temperature and pressure data as a function of time for systems undergoing a physicochemical change under nearly adiabatic conditions.1.2 This guide outlines the calculation of thermodynamic parameters from the time, temperature, and pressure data recorded by a calorimetric device.1.3 The assessment outlined in this guide may be used over a pressure range from full vacuum to the rated pressure of the reaction container and pressure transducer. The temperature range of the calorimeter typically varies from ambient to 500 °C, but also may be user specified (see 6.6).1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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. Specific safety precautions are outlined in Section 7.1.6 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.

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1.1 This specification addresses flexible protective jackets, made of a modified asphalt or butyl rubber sealing compound, for use over thermal insulation. The sealing compound is covered with an outer surface material. Typical applications are insulated ducts, pipe, and equipment. These materials shall be used only for outdoor or direct burial applications.1.2 The jacket materials covered by this specification have an allowed exposure temperature range, after installation, from –25°F to 284°F (–32°C to 140°C).1.3 This specification does not address installation methods of this jacketing material.1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.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.

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3.1 Unless there is a proper match between the expansions of the glaze and the body, all glazed whitewares may contain residual stresses from the firing that bonded the glaze to the body. In addition, whitewares are increasingly subjected to thermal stresses in service. Hence, an important use criterion for a glazed whiteware is adequate resistance to repeated abrupt thermal changes. In most cases, the result of inadequate resistance to thermal shock is the appearance of a craze pattern in the glaze. This craze pattern is visible by inspection with oblique lighting and application of a suitable ink or dye.3.2 This test method is applicable to vitreous whitewares that have negligible crazing as a result of moisture expansion. For nonvitreous and semivitreous bodies, refer to Test Method C424.1.1 This test method covers the determination of the resistance to crazing of fired, glazed, ceramic whitewares when stresses residual after glost firing may cause a tendency to craze, such stresses being induced by factors other than moisture expansion.1.2 This test is not intended to induce moisture expansion, which fact should be kept in mind if the materials to be evaluated may exhibit moisture expansion.NOTE 1: Test Method C424 covers a method for determining resistance to crazing induced by moisture expansion. Its use is generally confined to testing nonvitreous and semivitreous ceramic whitewares because these products may be subject to such expansion. For whitewares with negligible moisture expansion (such as vitreous and impervious ware), the thermal shock method described herein is generally to be preferred.1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.4 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. For a specific hazard statement, see Warning in 6.3.1.5 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.

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5.1 These test methods are to be used to determine the resistance of some types of preformed block insulation when transverse loads are normally applied to the surface. Values are measured at the maximum load or breaking point under specified conditions or specimen size, span between supports, and rate of load application. The equations used are based on the assumption that the materials are uniform and presume that the stress-strain characteristics below the elastic limit are linearly elastic. These assumptions are not strictly applicable to thermal insulations of certain types in which crushing occurs before failure is obtained in transverse bending; however, depending upon the accuracy required, these procedures are capable of providing acceptable results.5.2 Test Method I is especially useful when testing only for the modulus of rupture or the breaking load. This information is useful for quality control inspection and qualification for specification purposes.5.3 Test Method II is useful in determining the elastic modulus in bending as well as the flexural strength. Flexural properties determined by these test methods are also useful for quality control and specification purposes.5.4 The basic differences between the two test methods is in the location of the maximum bending moment, maximum axial fiber (flexural or tensile) stresses, and the resolved stress state in terms of shear stress and tensile/compression stress. The maximum axial fiber stresses occur on a line under the loading fitting in Test Method I and over the area between the loading fittings in Test Method II. Test Method I has a high shear stress component in the direction of loading, perpendicular to the axial fiber stress. Sufficient resolved shear stress is capable of producing failure by a shear mode rather than a simple tension/flexural failure. There is no comparable shear component in the central region between the loading fittings in Test Method II. Test Method II simulates a uniformly loaded beam in terms of equivalent stresses at the center of the specimen.5.5 Flexural properties are capable of varying with specimen span-to-thickness ratio, temperature, atmospheric conditions, and the difference in rate of straining specified in Procedures A and B. In comparing results it is important that all parameters be equivalent. Increases in the strain rate typically result in increased strengths and in the elastic modulus.1.1 These test methods cover the determination of the breaking load and calculated flexural strength of a rectangular cross section of a preformed block-type thermal insulation tested as a simple beam. It is also applicable to cellular plastics. Two test methods are described as follows:1.1.1 Test Method I—A loading system utilizing center loading on a simply supported beam, supported at both ends.1.1.2 Test Method II—A loading system utilizing two symmetric load points equally spaced from their adjacent support points at each end with a distance between load points of one half of the support span.1.2 Either test method is capable of being used with the four procedures that follow:1.2.1 Procedure A—Designed principally for materials that break at comparatively small deflections.1.2.2 Procedure B—Designed particularly for those materials that undergo large deflections during testing.1.2.3 Procedure C—Designed for measuring at a constant stress rate, using a CRL (constant rate of loading) machine. Used for breaking load measurements only.1.2.4 Procedure D—Designed for measurements at a constant crosshead speed, using either a CRT (constant rate of traverse) or CRE (constant rate of extension) machine. Used for breaking load measurements using a fixed crosshead speed machine.1.3 Comparative tests are capable of being run according to either method or procedure, provided that the method or procedure is found satisfactory for the material being tested.1.4 These test methods are purposely general in order to accommodate the widely varying industry practices. It is important that the user consult the appropriate materials specification for any specific detailed requirements regarding these test methods.1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information only.1.6 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. For specific precautionary statements, see Section 101.7 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.

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4.1 The methods in this practice are intended to aid in the assessment of long-term performance by comparative testing of absorptive materials. The results of the methods, however, have not been shown to correlate to actual in-service performance.4.2 The testing methodology in this practice provides two testing methods, in accordance with Fig. 1.FIG. 1 Outline of Test Method Options4.2.1 Method A, which aims at decreasing the time required for evaluation, uses a series of individual tests to simulate various exposure conditions.4.2.2 Method B utilizes a single test of actual outdoor exposure under conditions simulating thermal stagnation.4.2.3 Equivalency of the two methods has not yet been established.1.1 This practice covers a testing methodology for evaluating absorptive materials used in flat plate or concentrating collectors, with concentrating ratios not to exceed five, for solar thermal applications. This practice is not intended to be used for the evaluation of absorptive surfaces that are (1) used in direct contact with, or suspended in, a heat-transfer liquid, (that is, trickle collectors, direct absorption fluids, etc.); (2) used in evacuated collectors; or (3) used in collectors without cover plate(s).1.2 Test methods included in this practice are property measurement tests and aging tests. Property measurement tests provide for the determination of various properties of absorptive materials, for example, absorptance, emittance, and appearance. Aging tests provide for exposure of absorptive materials to environments that may induce changes in the properties of test specimens. Measuring properties before and after an aging test provides a means of determining the effect of the exposure.1.3 The assumption is made that solar radiation, elevated temperature, temperature cycles, and moisture are the primary factors that cause degradation of absorptive materials. Aging tests are described for exposure of specimens to these factors.NOTE 1: For some geographic locations, other factors, such as salt spray and dust erosion, may be important. They are not evaluated by this practice.1.4 The values stated in SI units are to be regarded as the standard.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.

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