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定价: 345元 / 折扣价: 294

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定价: 260元 / 折扣价: 221 加购物车

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This specification prescribes the standard nominal diameters and cross-sectional areas of American Wire Gage (AWG) sizes of solid round wires, used as electrical conductors, and gives equations and rules for the calculation of standard nominal mass and lengths, resistances, and breaking or rated strengths of such wires. All wire dimensions and properties shall be considered as occurring at the internationally standardized reference temperature and all calculations shall be rounded in the final value only.1.1 This specification prescribes standard nominal diameters and cross-sectional areas of American Wire Gage (AWG) sizes of solid round wires, used as electrical conductors, and gives equations and rules for the calculation of standard nominal mass and lengths, resistances, and breaking strengths of such wires (Explanatory Note 1).1.2 The values stated in inch-pound or SI units are to be regarded separately as standard. Each system shall be used independently of the other. Combining values of the two systems may result in nonconformance with the specification. For conductor sizes designated by AWG or kcmil sizes, the requirements in SI units have been numerically converted from the corresponding values stated or derived, in inch-pound units. For conductor sizes designated by SI units only, the requirements are stated or derived in SI units.1.2.1 For density, resistivity and temperature, the values stated in SI units are to be regarded as standard.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.

定价: 590元 / 折扣价: 502 加购物车

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This test method covers the standard procedure for determining the cross-sectional area of stranded conductors by the mass method. The apparatus shall consist of a balance for mass measurement, a steel scale for length measurement, and a jig or equivalent equipment for cutting the conductor to length and at right angles to its axis. Cross-sectional area of stranded conductors such as those with only one type of conducting material, cored annular conductors and steel-reinforced aluminum conductors, composite copper and copper-covered steel conductors, and composite aluminum 1350 and aluminum alloy 6201 conductor shall be calculated.1.1 This test method covers the procedure for determining the cross-sectional area of stranded conductors by the mass method.1.2 The values stated in inch-pound or SI units are to be regarded separately as the standard. The values in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the 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.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.

定价: 515元 / 折扣价: 438 加购物车

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4.1 This test method may be used for material development, material comparison, quality assurance, characterization, reliability assessment, and design data generation.4.2 Continuous fiber-reinforced ceramic matrix composites (CFCCs) are generally characterized by fine-grain sized (<50 μm) matrices and ceramic fiber reinforcements. In addition, continuous fiber-reinforced glass (amorphous) matrix composites can also be classified as CFCCs. Uniaxially loaded compressive strength tests provide information on mechanical behavior and strength for a uniformly stressed CFCC.4.3 Generally, ceramic and ceramic matrix composites have greater resistance to compressive forces than tensile forces. Ideally, ceramics should be compressively stressed in use, although engineering applications may frequently introduce tensile stresses in the component. Nonetheless, compressive behavior is an important aspect of mechanical properties and performance. The compressive strength of ceramic and ceramic composites may not be deterministic. Therefore, test a sufficient number of test specimens to gain an insight into strength distributions.4.4 Compression tests provide information on the strength and deformation of materials under uniaxial compressive stresses. Uniform stress states are required to effectively evaluate any nonlinear stress-strain behavior that may develop as the result of cumulative damage processes (for example, matrix cracking, matrix/fiber debonding, fiber fracture, delamination, etc.) that may be influenced by testing mode, testing rate, effects of processing or combination of constituent materials, or environmental influences. Some of these effects may be consequences of stress corrosion or sub-critical (slow) crack growth which can be minimized by testing at sufficiently rapid rates as outlined in this test method.4.5 The results of compression tests of test specimens fabricated to standardized dimensions from a particulate material or selected portions of a part, or both, may not totally represent the strength and deformation properties of the entire, full-size product or its in-service behavior in different environments.4.6 For quality control purposes, results derived from standardized compressive test specimens may be considered indicative of the response of the material from which they were taken for given primary processing conditions and post-processing heat treatments.4.7 The compressive behavior and strength of a CFCC are dependent on, and directly related to, the material. Analysis of fracture surfaces and fractography, though beyond the scope of this test method, are recommended.1.1 This test method covers the determination of compressive strength, including stress-strain behavior, under monotonic uniaxial loading of continuous fiber-reinforced advanced ceramics at ambient temperatures. This test method addresses, but is not restricted to, various suggested test specimen geometries as listed in the appendixes. In addition, test specimen fabrication methods, testing modes (force, displacement, or strain control), testing rates (force rate, stress rate, displacement rate, or strain rate), allowable bending, and data collection and reporting procedures are addressed. Compressive strength, as used in this test method, refers to the compressive strength obtained under monotonic uniaxial loading, where monotonic refers to a continuous nonstop test rate with no reversals from test initiation to final fracture.1.2 This test method applies primarily to advanced ceramic matrix composites with continuous fiber reinforcement: unidirectional (1D), bidirectional (2D), and tridirectional (3D) or other multi-directional reinforcements. In addition, this test method may also be used with glass (amorphous) matrix composites with 1D, 2D, 3D, and other multi-directional continuous fiber reinforcements. This test method does not directly address discontinuous fiber-reinforced, whisker-reinforced, or particulate-reinforced ceramics, although the test methods detailed here may be equally applicable to these composites.1.3 The values stated in SI units are to be regarded as the standard and are in accordance with IEEE/ASTM SI 10.1.4 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. Refer to Section 7 for specific precautions.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.

定价: 646元 / 折扣价: 550 加购物车

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4.1 This test method may be used for material development, material comparison, quality assurance, characterization, reliability assessment, and design data generation.4.2 Continuous fiber-reinforced ceramic matrix composites generally characterized by crystalline matrices and ceramic fiber reinforcements are candidate materials for structural applications requiring high degrees of wear and corrosion resistance, and elevated-temperature inherent damage tolerance (that is, toughness). In addition, continuous fiber-reinforced glass (amorphous) matrix composites are candidate materials for similar but possibly less demanding applications. Although flexural test methods are commonly used to evaluate strengths of monolithic advanced ceramics, the nonuniform stress distribution of the flexure test specimen, in addition to dissimilar mechanical behavior in tension and compression for CFCCs, leads to ambiguity of interpretation of strength results obtained from flexure tests for CFCCs. Uniaxially loaded tensile strength tests provide information on mechanical behavior and strength for a uniformly stressed material.4.3 Unlike monolithic advanced ceramics that fracture catastrophically from a single dominant flaw, CFCCs generally experience “graceful” (that is, non-catastrophic, ductile-like stress-strain behavior) fracture from a cumulative damage process. Therefore, the volume of material subjected to a uniform tensile stress for a single uniaxially loaded tensile test may not be as significant a factor in determining the ultimate strengths of CFCCs. However, the need to test a statistically significant number of tensile test specimens is not obviated. Therefore, because of the probabilistic nature of the strengths of the brittle fibers and matrices of CFCCs, a sufficient number of test specimens at each testing condition is required for statistical analysis and design. Studies to determine the influence of test specimen volume or surface area on strength distributions for CFCCs have not been completed. It should be noted that tensile strengths obtained using different recommended tensile test specimen geometries with different volumes of material in the gage sections may be different due to these volume differences.4.4 Tensile tests provide information on the strength and deformation of materials under uniaxial tensile stresses. Uniform stress states are required to effectively evaluate any nonlinear stress-strain behavior that may develop as the result of cumulative damage processes (for example, matrix cracking, matrix/fiber debonding, fiber fracture, delamination, and so forth) that may be influenced by testing mode, testing rate, effects of processing or combinations of constituent materials, environmental influences, or elevated temperatures. Some of these effects may be consequences of stress corrosion or subcritical (slow) crack growth that can be minimized by testing at sufficiently rapid rates as outlined in this test method.4.5 The results of tensile tests of test specimens fabricated to standardized dimensions from a particular material or selected portions of a part, or both, may not totally represent the strength and deformation properties of the entire, full-size end product or its in-service behavior in different environments or various elevated temperatures.4.6 For quality control purposes, results derived from standardized tensile test specimens may be considered indicative of the response of the material from which they were taken for the particular primary processing conditions and post-processing heat treatments.4.7 The tensile behavior and strength of a CFCC are dependent on its inherent resistance to fracture, the presence of flaws, or damage accumulation processes, or both. Analysis of fracture surfaces and fractography, though beyond the scope of this test method, is recommended.1.1 This test method covers the determination of tensile strength, including stress-strain behavior, under monotonic uniaxial loading of continuous fiber-reinforced advanced ceramics at elevated temperatures. This test method addresses, but is not restricted to, various suggested test specimen geometries as listed in the appendixes. In addition, test specimen fabrication methods, testing modes (force, displacement, or strain control), testing rates (force rate, stress rate, displacement rate, or strain rate), allowable bending, temperature control, temperature gradients, and data collection and reporting procedures are addressed. Tensile strength as used in this test method refers to the tensile strength obtained under monotonic uniaxial loading, where monotonic refers to a continuous nonstop test rate with no reversals from test initiation to final fracture.1.2 This test method applies primarily to advanced ceramic matrix composites with continuous fiber reinforcement: unidirectional (1D), bidirectional (2D), and tridirectional (3D) or other multi-directional reinforcements. In addition, this test method may also be used with glass (amorphous) matrix composites with 1D, 2D, 3D, and other multi-directional continuous fiber reinforcements. This test method does not directly address discontinuous fiber-reinforced, whisker-reinforced, or particulate-reinforced ceramics, although the test methods detailed here may be equally applicable to these composites.1.3 The values stated in SI units are to be regarded as the standard and are in accordance with IEEE/ASTM SI 10.1.4 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. Refer to Section 7 for specific precautions.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.

定价: 843元 / 折扣价: 717 加购物车

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This specification covers cold expansion fittings and cross-linked (PEX) reinforcing rings for use with cross-linked polyethylene (PEX) plastic tubing in specific nominal diameters. These fittings are intended for use in residential and commercial, hot and cold, potable water distribution systems as well as sealed central heating, including under-floor-heating systems. The PEX reinforcing rings shall conform to the required density, degree of cross-linking, and stabilizer migration resistance.1.1 This specification covers cold expansion fittings and cross-linked (PEX) reinforcing rings for use with cross-linked polyethylene (PEX) plastic tubing in nominal tubing sizes of 3/8 , 1/2 , 5/8 , 3/4 , 1, 11/4 , 11/2 , 2, 21/2 , and 3 in. that meet the requirements of Specification F876 or F3253 and for use with Polyethylene of Raised Temperature (PE-RT) pipe in nominal tubing sizes of 3/8 , 1/2 , 5/8 , 3/4 , 1, 11/4 , 11/2 , 2, 21/2 , and 3 that meet the requirements of Specification F2769. These fittings are intended for use in 100 psi (690 kPa) cold- and hot-water distribution systems operating at temperatures up to and including 180 °F (82 °C). The system is comprised of a PEX reinforcing ring and a cold expansion fitting. Included are the requirements for materials, workmanship, dimensions, and markings to be used on the fitting components. The components covered by this specification are intended for use in residential and commercial, hot and cold, potable water distribution systems as well as building supply lines, sealed central heating, including under-floor-heating systems.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.

定价: 590元 / 折扣价: 502 加购物车

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5.1 This guide provides a means of using an LD instrument to obtain a droplet size distribution from a spray in gas co-flow that approximates a flux-sensitive sample.45.2 In many sprays, the experimenter shall account for spatial segregation of droplets by size. This guide provides a means of spatial averaging the droplet distribution.5.3 The results obtained will be statistical in nature and refer to the time average of droplet size distribution of the entire spray.5.4 This guide is used to calibrate a spray generation device to produce a desired droplet size distribution under prespecified environmental and co-flow conditions or characterize an unknown spray while minimizing the uncertainty in the measurement.1.1 The purpose of this guide is to define a test procedure for applying the laser diffraction (LD) method to estimate an average droplet size distribution that characterizes the flux of liquid droplets produced by a specified spray generation device under specified gas co-flow conditions using a specified liquid. The intended scope is limited to artificially generated sprays with high speed co-flow. The droplets are assumed to be in the size range of 1 to 2000 µm in diameter and occur in sprays that are contained within a volume as small as a few cubic centimetres or as large as a cubic metre. The droplet sizes are assumed to be distributed non-uniformly within the spray volume.1.2 This guide is intended primarily to guide measurement of performance of nozzles and atomizers using LD instruments.1.3 Non-uniform sprays require measurements across the entire spray cross section or through several chords providing a representative sample of the overall spray cross section. The aim of multiple-chord measurements is to obtain a single droplet size distribution that characterizes the whole spray rather than values from a single chordal measurement.1.4 Use of this guide requires that the instrument does not interfere with spray production and does not significantly impinge upon or disturb the co-flow of gas and the spray. This technique is, therefore, considered non-intrusive.1.5 The computation of droplet size distributions from the light-scattering distributions is done using Mie scattering theory or Fraunhofer diffraction approximation. The use of Mie theory accounts for light refracted through the droplet and there is a specific requirement for knowledge of both real (refractive) and imaginary (absorptive) components of the complex index of refraction. Mie theory also relies on an assumption of droplet homogeneity. The Fraunhofer diffraction approximation does not account for light refracted through the droplet and does not require knowledge of the index of refraction.1.6 The instruments shall include data-processing capabilities to convert the LD scattering intensities into droplet size distribution parameters in accordance with Practice E799 and Test Method E1260.1.7 The spray is visible and accessible to the collimated beam produced by the transmitter optics of the LD instrument. The shape and size of the spray shall be contained within the working distance of the LD system optics as specified by the instrument manufacturer.1.8 The size range of the LD optic should be appropriate to the spray generation device under study. For example, the upper bound of the smallest droplet size class reported by the instrument shall be not more than 1/4 the size of DV0.1.1.9 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.10 This standard may involve hazardous materials, operations, and equipment. 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.1.11 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.

定价: 590元 / 折扣价: 502 加购物车

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5.1 Many coating properties are markedly affected by the film thickness of the dry film such as adhesion, flexibility, and harness. To be able to compare results obtained by different operators, it is essential to measure film thickness carefully.5.2 Most protective and high performance coatings are applied to meet a requirement or a specification for the dry-film thickness of each coat, or for the complete system, or both. Coatings must be applied within a certain minimum and maximum thickness tolerances in order that they can fulfill their intended function.1.1 This practice describes the measurement of dry film thickness of coating films by microscopic observation of precision angular cuts in the coating film. Use of these procedures may require repair of the coating film. This practice is intended to supplement the manufacturers' instructions for the manual operation of the gages and is not intended to replace them. It includes definitions of key terms, reference documents, the significance and use of the practice, and the advantages and limitations of the instruments.1.2 Three procedures are provided for measuring dry film thickness of protective coating systems:1.2.1 Procedure A—Using groove cutting instruments.1.2.2 Procedure B—Using grinding instruments.1.2.3 Procedure C—Using drill bit instruments.1.3 These procedures are not applicable for soft or ductile substrates that may deform under the test gage cutting tip. The substrate should be sufficiently rigid to prevent deformation of the coating during the cutting process. The surface may be flat or moderately curved. Pipes as small as 25 mm (1 in.) in diameter may be measured in the axial direction.1.4 Individual coats in a multicoat system where there is a discernible visual difference between coats or the overall thickness of a coating system can be measured by these procedures.1.5 The range of thickness measurement is typically 2 to 2000 microns (0.1 to 80 mils) and depends upon the cutting angle of the blade.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.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.

定价: 590元 / 折扣价: 502 加购物车

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