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3.1 This test method is used to determine the modulus of rupture of specimens prepared and cured in accordance with Practices C31/C31M or C192/C192M. The strength determined will vary where there are differences in specimen size, preparation, moisture condition, or curing.3.2 The results of this test method may be used to determine compliance with specifications or as a basis for proportioning, mixing and placement operations. This test method produces values of flexural strength significantly higher than Test Method C78/C78M.1.1 This test method covers determination of the flexural strength of concrete specimens by the use of a simple beam with center-point loading. Test Method C293/C293M is not an alternative to Test Method C78/C78M.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the 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 and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 Flash point measures the response of the test specimen to heat and ignition source under controlled laboratory conditions. It is only one of a number of properties that must be considered in assessing the overall flammability hazard of a material.5.2 Flash point is used in shipping and safety regulations by governmental regulatory agencies to define flammable and combustible materials and to classify them. Consult the particular regulation involved for precise definitions of these classes.5.3 Flash point can indicate the possible presence of highly volatile and flammable impurities or contaminants in a given liquid, such as the presence of residual solvents in solvent-refined drying oils.5.4 These equilibrium flash point test methods use a smaller specimen (2 mL) and a shorter test time (1 min) than traditional non-equilibrium test methods such as Test Method D56 and Test Methods D93.5.5 Test Methods D3828, Test Method D8174, and ISO 3679 are similar test methods and use the same apparatus.1.1 These test methods cover procedures for determining whether a material does or does not flash at a specified temperature (flash/no flash Method A) or for determining the lowest finite temperature at which a material does flash (Method B), when using a small scale closed-cup apparatus. The test methods are applicable to paints, enamels, lacquers, varnishes, solvents, and related products having a flash point between 0 °C and 110 °C (32 °F and 230 °F) and viscosity lower than 15 000 mm2/s (cSt) at 25 °C (77 °F).NOTE 1: Tests at higher or lower temperatures are possible however the precision has not been determined.NOTE 2: More viscous materials can be tested in accordance with Annex A4.NOTE 3: Organic peroxides can be tested in accordance with Annex A5, which describes the applicable safety precautions.NOTE 4: The U.S. Department of Labor (OSHA, Hazard Communications), the U.S. Department of Transportation (RSPA), and the U.S. Environmental Protection Agency (EPA) have specified Test Methods D3278 as one of several acceptable methods for the determination of flash point of liquids in their regulations.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.3 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.1.4 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.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 The flash point temperature is one measure of the tendency of the test specimen to form a flammable mixture with air under controlled laboratory conditions. It is only one of a number of properties which must be considered in assessing the overall flammability hazard of a material.5.2 Flash point is used in shipping and safety regulations to define flammable and combustible materials and for classification purposes. This definition may vary from regulation to regulation. Consult the particular regulation involved for precise definitions of these classifications.5.3 This test method can be used to measure and describe the properties of materials in response to heat and an ignition source under controlled laboratory conditions and shall not be used to describe or appraise the fire hazard or fire risk of materials under actual fire conditions. However, results of this test method may be used as elements of a fire risk assessment, which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use.5.4 Flash point can also indicate the possible presence of highly volatile and flammable materials in a relatively nonvolatile or nonflammable material, such as the contamination of lubricating oils by small amounts of diesel fuel or gasoline. This test method was designed to be more sensitive to potential contamination than Test Method D6450.1.1 This test method covers the determination of the flash point of fuels including diesel/biodiesel blends, lube oils, solvents, and other liquids by a continuously closed cup tester utilizing a specimen size of 2 mL, cup size of 7 mL, with a heating rate of 2.5 °C per minute.1.1.1 Apparatus requiring a specimen size of 1 mL, cup size of 4 mL, and a heating rate of 5.5 °C per minute must be run according to Test Method D6450.1.2 This flash point test method is a dynamic method and depends on definite rates of temperature increase. It is one of the many flash point test methods available and every flash point test method, including this one, is an empirical method.NOTE 1: Flash point values are not a constant physical chemical property of materials tested. They are a function of the apparatus design, the condition of the apparatus used, and the operational procedure carried out. Flash point can, therefore, only be defined in terms of a standard test method and no general valid correlation can be guaranteed between results obtained by different test methods or where different test apparatus is specified.1.3 This test method utilizes a closed but unsealed cup with air injected into the test chamber.1.4 The precision of this test method is applicable for testing samples with a flash point from 22.5 °C to 235.5 °C. Determinations below and above this range may be performed; however, the precision has not been established.1.5 If the user’s specification requires a defined flash point method other than this method, neither this method nor any other test method should be substituted for the prescribed test method without obtaining comparative data and an agreement from the specifier.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. Temperatures are in degrees Celsius, pressure in kilo-Pascals.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. For specific warning statements, see 7.2 and 8.5.1.8 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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5.1 The crystallinity of UHMWPE will influence its mechanical properties, such as creep and stiffness. The reported crystallinity will depend on the integration range used to determine the heat of fusion, and the theoretical heat of fusion of 100 % crystalline polyethylene used to calculate the percent crystallinity in an unknown specimen. Differential scanning calorimetry is an effective means of accurately measuring both heat of fusion and melting temperature.5.2 This test method is useful for both process control and research.1.1 This test method discusses the measurement of the heat of fusion and the melting point of ultra-high-molecular weight polyethylene (UHMWPE), and the subsequent calculation of the percentage of crystallinity.1.2 This test method can be used for UHMWPE in powder form, consolidated form, finished product, or a used product. It can also be used for irradiated or chemically-crosslinked UHMWPE.1.3 This test method does not suggest a desired range of crystallinity or melting points for specific applications.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 and health practices and determine the applicability of regulatory limitations prior to use.

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This specification establishes the baseline performance requirements and additional optional capabilities for stationary point chemical vapor detectors (SPCVD) intended for continuous monitoring of public, non-industrial facilities 24 hours a day, 7 days a week. It provides SPCVD designers, manufacturers, integrators, procurement personnel, end users/practitioners, and responsible authorities a common set of parameters to match capabilities and user needs. The document specifies chemical detection performance requirements, system requirements, environmental requirements, manuals and documentation, and product marking.1.1 General:1.1.1 This specification presents baseline performance requirements and additional optional capabilities for stationary point chemical vapor detectors (SPCVD) designed for continuous, 24 h a day 7 days a week, monitoring of public, non-industrial facilities. This specification is one of several that describe chemical vapor detectors (for example, handheld and stationary) and chemical detection capabilities including: chemical vapor hazard detection, identification, classification, and quantification. An SPCVD is capable of detecting and alarming when exposed to chemical vapors that pose a risk as defined by the Acute Exposure Guideline Levels for Selected Airborne Chemicals (AEGL). For example, chemical vapors of interest for homeland security applications, see Appendix X1. The SPCVD should not alarm to background chemical vapors and should provide low false positive alarm rates and no false negatives. Procurement agents and end users must identify the specific chemicals of interest and environmental requirements for the given facility.1.1.1.1 An SPCVD samples air from immediate surroundings and is comprised of one or more detectors using one or more chemical detection technologies. An SPCVD also includes air sampling system(s), power system(s), computer(s), data storage, data network communication interface(s), and an enclosure, see Fig. 1. An SPCVD may be combined with other SPCVDs, other chemical, biological, radiological, nuclear, and explosive (CBRNE) detectors, and other monitoring devices such as video. A remote command center may monitor and control these devices and communicate information to the responsible authorities and responders, as depicted in Fig. 2.FIG. 1 An Example Schematic of a Stationary Point Chemical Vapor Detector (SPCVD)The SPCVD is a unit which samples air from immediate surroundings and is comprised of one or more detectors using one or more chemical detection technologies. An SPCVD also includes air sampling system(s), power system(s), computer(s), data storage, data network communication interface(s), and an enclosure.FIG. 2 A Conceptual Representation of a Facility Security System with Stationary Point Chemical Vapor Detectors (SPCVDs) integrated with other Chemical, Biological, Radiological, Nuclear, and Explosive (CBRNE) Detectors, and Other Monitoring Devices such as Video1.1.2 This specification provides the SPCVD baseline requirements, including performance, system, environmental, and documentation requirements. This specification provides SPCVD designers, manufacturers, integrators, procurement personnel, end users/practitioners, and responsible authorities a common set of parameters to match capabilities and user needs.1.1.3 This specification is not meant to provide for all uses. Manufacturers, purchasers, and end users will need to determine specific requirements based on the installation location and environment.1.2 SPCVD Chemical Detection Capabilities—Manufacturers document and verify, through testing, the chemical detection capabilities of the SPCVD. Test methods for assessing chemical detection capabilities are available from the Department of Homeland Security and the Department of Defense and are listed in Appendix X2.1.3 SPCVD System and Environmental Properties—Manufacturers document and verify, through testing, the system and environmental properties of the SPCVD. Example test methods for assessing the system and environmental properties are listed in Appendix X3.1.4 Units—The values stated in SI units are to be regarded as standard. Vapor concentrations of the hazardous materials are presented in parts per million (ppm) as used in Acute Exposure Guideline Levels for Selected Airborne Chemicals, Vols 1-9 (see 2.2) and in mg/m3.1.5 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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5.1 This test method provides a simple means of characterizing the thermomechanical behavior of plastic compositions using very small amounts of material. The data obtained is used for quality control, research and development as well as the establishment of optimum processing conditions.5.2 Dynamic mechanical testing provides a sensitive means for determining thermomechanical characteristics by measuring the elastic and loss moduli as a function of frequency, temperature, or time. Plots of moduli and tan delta of a material versus these variables can be used to provide a graphical representation indicative of functional properties, effectiveness of cure (thermosetting resin system), and damping behavior under specified conditions.5.2.1 Observed data are specific to experimental conditions. Reporting in full (as described in this test method) the conditions under which the data was obtained is essential to assist users with interpreting the data an reconciling apparent or perceived discrepancies.5.3 This test method can be used to assess:5.3.1 Modulus as a function of temperature,5.3.2 Modulus as a function of frequency,5.3.3 The effects of processing treatment,5.3.4 Relative resin behavioral properties, including cure and damping.5.3.5 The effects of substrate types and orientation (fabrication) on modulus,5.3.6 The effects of formulation additives which might affect processability or performance,5.3.7 The effects of annealing on modulus and glass transition temperature,5.3.8 The effect of aspect ratio on the modulus of fiber reinforcements, and5.3.9 The effect of fillers, additives on modulus and glass transition temperature.5.4 Before proceeding with this test method, refer to the specification of the material being tested. Any test specimen preparation, conditioning, dimensions, or testing parameters, or combination thereof, covered in the relevant ASTM materials specification shall take precedence over those mentioned in this test method. If there are no relevant ASTM material specifications, then the default conditions apply.1.1 This test method outlines the use of dynamic mechanical instrumentation for determining and reporting the visco-elastic properties of thermoplastic and thermosetting resins and composite systems in the form of rectangular bars molded directly or cut from sheets, plates, or molded shapes. The data generated, using three-point bending techniques, is used to identify the thermomechanical properties of a plastic material or compositions using a variety of dynamic mechanical instruments.1.2 This test method is intended to provide means for determining the viscoelastic properties of a wide variety of plastics materials using nonresonant, forced-vibration techniques in accordance with Practice D4065. Plots of the elastic (storage) modulus; loss (viscous) modulus; complex modulus and tan delta as a function of frequency, time, or temperature are indicative of significant transitions in the thermomechanical performance of polymeric material systems.1.3 This test method is valid for a wide range of frequencies, typically from 0.01 Hz to 100 Hz.1.4 Due to possible instrumentation compliance, the data generated are intended to indicate relative and not necessarily absolute property values.1.5 Test data obtained by this test method are relevant and appropriate for use in engineering design.1.6 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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.NOTE 1: This test method is equivalent to ISO 6721, Part 5.1.8 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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4.1 In general, with materials of this type, softening does not take place at a definite temperature. As the temperature rises, these materials gradually and imperceptibly change from brittle solids to soft, viscous liquids. For this reason, the determination of the softening point must be made by a fixed, arbitrary, and closely defined methods if the results are to be comparable.1.1 This test method covers the determination of the softening point of certain alkali-soluble resins having uniform plastic flow characteristics as the melting point is approached.1.2 The resin manufacturer should specify whether or not this test method may be used for his product(s).1.3 This test method is not suitable for styrene-maleic anhydride resins.NOTE 1: For testing rosin and other resins, see Test Method E28. For testing asphalts, tars, and pitches, see Test Method D2398.1.4 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.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 The flash point measures the response of the sample to heat and flame under controlled laboratory conditions. It is only one of a number of properties that must be considered in assessing the overall flammability hazard of a material.5.2 As a result of physical factors inherent in the apparatus and procedure, the closed cup flash point does not necessarily represent the minimum temperature at which a material can evolve flammable vapors, and the absence of a flash point does not guarantee nonflammability (see Appendix X1 and Appendix X2).5.3 Flash point is used in shipping and safety regulations to define flammable and combustible materials. Test Methods D56, D93, and D3278 are specified as test methods for determining the flash point of these materials.5.4 If the process or handling conditions dictate the usage of a flammable material at temperatures ranging upward from 5 to 10°C below the closed-cup flash point, then a flammable vapor might be present above the liquid. In such cases, it may be more appropriate to use the temperature limit of flammability (as determined by Test Method E1232) instead of flash point.5.5 For single component samples, small-scale methods involving equilibrium procedures and only one flame pass per specimen are preferred.5.6 For mixtures containing small concentrations of volatile components, special procedures are needed to minimize the loss of volatiles, with consequent elevation of the flash point, while the sample is being heated. (See X2.5.)5.7 In cases where errors caused by loss of volatiles, downwards flame direction and quenching are unacceptable, the “lower temperature limit of flammability” can be determined instead using Test Method E1232. The temperature limit of flammability test chamber is sufficiently large to overcome flame quenching effects in most cases of practical importance, thus, usually indicating the presence of vapor-phase flammability if it does exist.1.1 This test method covers the determination of the flash point of liquid and solid chemical compounds flashing from below −10 to 370°C (16 to 700°F). The procedures and apparatus in Test Methods D56, D93, D3278, D3828, and D3941 are to be used. Modification to these procedures are specified for tests on solids and viscous liquids. The significance of the results obtained is discussed along with possible sources of error and factors that might cause interference.1.2 Suggestions for adapting this procedure to mixtures of chemicals are included (see Appendix X2).1.3 This test method should be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials or assemblies under actual fire conditions. However, results of this test method may be used as elements of a fire risk assessment that take into account all of the factors that are pertinent to an assessment of the fire hazard of a particular end use.1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.5 Warning—Mercury has been designated by the United States Environmental Protection Agency (EPA) and many state agencies as a hazardous material that can cause central nervous system, kidney, and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. See the applicable product Material Safety Data Sheet (MSDS) for details and EPA’s website — http://www.epa.gov/mercury/faq.htm — for additional information. Users should be aware that selling mercury or mercury-containing products, or both, into your state may be prohibited by state law.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. See also Section 8.1.7 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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3.1 This practice is useful in determining the viscosity-temperature relationships for glasses and corresponding useful working ranges. See Terminology C162.1.1 This practice covers the determination of the viscosity of glass above the softening point through the use of a platinum alloy spindle immersed in a crucible of molten glass. Spindle torque, developed by differential angular velocity between crucible and spindle, is measured and used to calculate viscosity. Generally, data are taken as a function of temperature to describe the viscosity curve for the glass, usually in the range from 1 to 106 Pa·s.1.2 Two procedures with comparable precision and accuracy are described and differ in the manner for developing spindle torque. Procedure A employs a stationary crucible and a rotated spindle. Procedure B uses a rotating crucible in combination with a fixed spindle.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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4.1 This test method provides data useful for (1) estimating stress release, (2) the development of proper annealing schedules, and (3) estimating setting points for seals. Accordingly, its usage is widespread throughout manufacturing, research, and development. It can be utilized for specification acceptance.1.1 This test method covers the determination of the annealing point and the strain point of a glass by measuring the viscous elongation rate of a fiber of the glass under prescribed condition.1.2 The annealing and strain points shall be obtained by following the specified procedure after calibration of the apparatus using fibers of standard glasses having known annealing and strain points, such as those specified and certified by the National Institute of Standards and Technology (NIST)2 (see Appendix X1).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 C338-93(2019) Standard Test Method for Softening Point of Glass Active 发布日期 :  1970-01-01 实施日期 : 

2.1 This test method is useful to determine approximately the temperature below which the glass behaves as a rigid solid in glass-forming operations and for a control test to indicate changes in composition. It has been found useful for specification acceptance and for providing information in research and development work with glass.1.1 This test method covers the determination of the softening point of a glass by determining the temperature at which a round fiber of the glass, nominally 0.65 mm in diameter and 235 mm long with specified tolerances, elongates under its own weight at a rate of 1 mm/min when the upper 100 mm of its length is heated in a specified furnace at the rate of 5 ± 1 °C/min.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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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5.1 The solidification point of bisphenol A is a direct indication of its purity, although it gives no information as to the nature of any impurities present.5.2 High purity bisphenol A has a solidification point of approximately 157°C.5.3 This test method can be used for internal quality control or for setting specifications.1.1 This test method describes the procedure for determination of the solidification point of bisphenol A (4,4′-isopropylidene diphenol).1.2 The test method has been found applicable for determination of the solidification point between 150 and 157°C.1.3 In determining conformance of the test results using this method to applicable specifications, results shall be rounded off in accordance with the rounding-off method of Practice E29.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 Warning—Mercury has been designated by many regulatory agencies as a hazardous substance that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Use caution when handling mercury and mercury-containing products. See the applicable product Safety Data Sheet (SDS) for additional information. The potential exists that selling mercury or mercury-containing products, or both, is prohibited by local or national law. Users must determine legality of sales in their location.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 hazard statements, see Section 9.1.7 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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5.1 A pure material has a well defined phase transition behavior, and the phase transition plateau, a characteristic of the material, can serve as a reproducible reference temperature for the calibration of thermometers. The melting or freezing points of some highly purified metals have been designated as defining fixed points on ITS-90. The fixed points of other materials have been determined carefully enough that they can serve as secondary reference points (see Tables 1 and 2). This guide presents information on the phase transition process as it relates to establishing a reference temperature.(A) Defining fixed point for ITS-90.(B) Realized as melting point.(C) Based on recommendation of International Bureau of Weights and Measures (BIPM) Working Group 2 of the Comité Consultatif de Thermométrie (CCT-WG2); published as: Bedford, R. E., Bonnier, G., Maas, H., and Pavese, F., "Recommended Values of Temperature on the International Temperature Scale of 1990 for a Selected Set of Secondary Reference Points", Metrologia, Vol 33, 1996, pp. 133. DOI: 10.1088/0026-1394/33/2/3.(A) Values for cells of good design, construction, and material purity used with careful technique. Cells of lesser quality may not approach these values.(B) Realized as melting point.5.2 Fixed-point cells provide users with a means of realizing melting and freezing points. If the cells are appropriately designed and constructed, if they contain material of adequate purity, and if they are properly used, they can establish reference temperatures with uncertainties of a few millikelvins or less. This guide describes some of the design and use considerations.5.3 Fixed-point cells can be constructed and operated less stringently than required for millikelvin uncertainty, yet still provide reliable, durable, easy-to-use fixed points for a variety of industrial calibration and heat treatment purposes. For example, any freezing-point cell can be operated, often advantageously, as a melting-point cell. Such use may result in reduced accuracy, but under special conditions, the accuracy may be commensurate with that of freezing points (see 6.3.10).5.4 The test procedure described in this guide produces qualification test data as an essential part of the procedure. These data furnish the basis for quality control of the fixed-point procedure. They provide for evaluation of results, assure continuing reliability of the method, and yield insight into the cause of test result discrepancies. The test procedure is applicable to the most demanding uses of fixed-point cells for precise thermometer calibration; it may not be appropriate or cost-effective for all applications. It is expected that the user of this guide will adapt the procedure to specific needs.1.1 This guide describes the essential features of fixed-point cells and auxiliary apparatus, and the techniques required to realize fixed points in the temperature range from 29 °C to 1085 °C.31.2 Design and construction requirements of fixed-point cells are not addressed in this guide. Typical examples are given in Figs. 1 and 2.FIG. 1 Examples of Fixed-Point CellsFIG. 2 Example of Fixed-Point FurnaceNOTE 1: This example shows an insulated furnace body and two alternative types of furnace cores. The core on the left is a three-zone shielded type. The core on the right employs a heat pipe to reduce temperature gradients.1.3 This guide is intended to describe good practice and establish uniform procedures for the realization of fixed points.1.4 This guide emphasizes principles. The emphasis on principles is intended to aid the user in evaluating cells, in improving technique for using cells, and in establishing procedures for specific applications.1.5 For the purposes of this guide, the use of fixed-point cells for the accurate calibration of thermometers is restricted to immersion-type thermometers that, when inserted into the reentrant well of the cell, (1) indicate the temperature only of the isothermal region of the well, and (2) do not significantly alter the temperature of the isothermal region of the well by heat transfer.1.6 This guide does not address all of the details of thermometer calibration.1.7 This guide is intended to complement special operating instructions supplied by manufacturers of fixed-point apparatus.1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.9 The following hazard caveat pertains only to the test method portion, Section 7, of this guide. 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.1.10 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 the method of determining and designating the balance point location of an arrow assembly for use with an archery bow. The base for determining the percentage location of the balance point of the arrow assembly shall be the ATA (Archery Trade Association) arrow length. When the balance point of the arrow is determined, the arrow assembly shall be complete with all components, including the arrow point in place and mounted securely ready for shooting. In determining the balance point, the arrow assembly shall be placed on a knife edge and moved longitudinally until perfect balance is achieved. The FOC (front of center) shall be measured as follows: from the bottom of nock slot, measure the distance from the bottom of the nock slot to the balance point; or from the front of the shaft assembly, measure the distance from the designated point to the balance point. The percent FOC shall be calculated using the specified formula. The following arrow assemblies are illustrated: (1) arrow assembly employing an interchangeable point insert (2) arrow assembly having the front end of the shaft tapered or swaged, (3) arrow assembly incorporating an outsert, and (4) arrow assembly with a head that has an integral cylindrical socket.1.1 This specification covers the method of determining and designating the location of the balance point of an arrow assembly for use with an archery bow.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.

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This test method describes the optical emission vacuum spectrometric procedure for examining blast furnace iron (hot metal) containing 4.2 to 5.0 % carbon by the point-to-plane technique. This spectrochemical technique is intended specifically for the analysis of silicon, manganese, phosphorus, titanium, and sulfur in specified concentration ranges in blast furnace iron. Apparatus needed for this procedure shall include sample mold, grinder, supporting electrode, excitation source, spectrometer, and appropriate measuring system. The sample is excited in an inert gas atmosphere by a controlled triggered capacitor discharge using the point-to-plane technique. Using a vacuum spectrometer, the radiant energies of selected analytical lines and an internal standard line are measured by photomultipliers. The output current of each photomultiplier is accumulated and stored during the exposure period as a charge on an associated capacitor, where it appears as a measurable voltage. At the end of the exposure period the voltages corresponding to the analytical lines relative to the voltage for the internal standard line are measured. The measuring system may be calibrated in terms of percent concentration.1.1 This test method describes the spectrochemical procedure for the analysis of blast furnace iron (hot metal) containing 4.2 to 5.0 % carbon for the following elements in the indicated ranges:Elements Concentration Range, %Silicon 0.50 to 2.00Manganese 0.20 to 1.50Phosphorus 0.020 to 0.15Titanium 0.02 to 0.10Sulfur 0.010 to 0.0501.2This 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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