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4.1 These test methods are intended to measure the anchoring capability and shear resistance of power-actuated fasteners to provide information from which applicable design values are to be derived for use in structural applications, such as in members of concrete, concrete masonry, and steel.1.1 These test methods describe procedures for determining the static axial tensile and shear strengths of power-actuated fasteners installed in structural members made of concrete, concrete masonry, and steel.1.2 These test methods are intended for use with fasteners that are installed perpendicular to a plane surface of the structural member.1.3 Tests for combined tension and shear, fatigue, dynamic, and torsional load resistance are not covered.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 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 hazard statements are given in Section 6.1.6 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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4.1 This test method is designed to provide a uniform test to determine the suitability of Coating Service Level 1 coatings used inside primary containment of light-water nuclear facilities under simulated DBA conditions. This test method is intended only to demonstrate that under DBA conditions, the coatings will remain intact and not form debris which could unacceptably compromise the operability of engineered safety systems. Deviations in actual surface preparation and in application and curing of the coating materials from qualification test parameters require an engineering evaluation to determine if additional testing is required.4.2 Since different plants have different tolerance levels for coating conditions, the definition of appropriate acceptance criteria is to be developed by the license holder based on individual plant engineered safety systems operability considerations.4.3 Use of this standard is predicated on the testing facility having a quality assurance program acceptable to the licensee.1.1 This test method establishes procedures for evaluating protective coating systems test specimens under simulated DBA conditions. Included are a description of conditions and apparatus for temperature-pressure testing, and requirements for preparing, irradiating, testing, examining, evaluating, and documenting the samples.1.2 Consideration should be given to testing using worst case conditions (for example, surface preparation, temperature and pressure profile, irradiation, spray chemistry, chemical resistance, etc.) in an effort to reduce the number of tests required by changing plant accident calculations, changes in coating selection, etc.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.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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3.1 The lining test described in 6.2 may be used to evaluate the chemical resistance characteristics of coating systems for lining surfaces of tanks, vessels and similar facilities used in Coating Service Level I and II applications in a nuclear power plant. For the evaluation of linings in Coating Service Level III water immersion applications in nuclear power plants use the test methods and guidance found in Guide D7230.3.2 The specific chemical resistance tests described in 6.1 are dependent upon the relative severity of the service conditions. The specific chemical reagents to be used shall be specified to reflect the intended service conditions.3.3 At the discretion of the user, the methods presented may also be used to evaluate coatings and linings for applications in other types of power plants or other industrial services.1.1 This test method establishes procedures for the evaluation of the chemical resistance of coatings and linings for use in Coating Service Level I and II applications in nuclear power plants.1.2 This test method is intended to be used as a screening test to evaluate coatings and linings on steel and concrete substrates.1.3 This test method addresses two exposure intervals:(1) Short Term (Typically 5 days): Such exposures are primarily applicable for coatings exposed to chemical splash or spill.(2) Long Term (Typically 180 days): Such exposures are primarily applicable for linings exposed to continuous or near-continuous chemical immersion.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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5.1 Fabric stretch and fabric growth are useful in selection of fabrics that are required to stretch, but also recover to their original shape.5.1.1 In apparel, fabric stretch can be caused by a variety of factors. A momentary stress occurs when a fabric is required to accommodate movement, such as sportswear and other loose-fitting apparel (also known as comfort stretch apparel) or external stress such as grabbing and pulling. Additionally, comfort apparel can be subjected to prolonged stress, such as stretching to accommodate positions such as sitting. Another example of prolonged stress occurs when a fabric is required to stretch to accommodate fitting the form of the body, such as swimwear, anchored slacks, and other form-fitting apparel (also known as semi-support apparel).5.1.2 Fabric growth can also be in response to a variety of stresses. This method evaluates fabric growth due to exposure to prolonged stresses. In form-fitting apparel, fabric growth can apply as garments are worn for a prolonged period of time or under long periods of stress such as sitting. Upon removal of garments or stress, its growth can be seen and evaluated.5.2 This test method is not recommended for acceptance testing of commercial shipment because the between-laboratory precision is known to be poor.5.2.1 If there are differences of practical significance between reported test results for two laboratories (or more), comparative tests should be performed to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, ensure the test samples to be used are as homogeneous as possible, are drawn from the material from which the disparate test results are obtained, and are assigned randomly in equal numbers to each laboratory for testing. The test results from the two laboratories should be compared using a statistical test for unpaired data, at a probability level chosen prior to the testing series. If a bias is found, either its cause must be found and corrected, or future test results for that material must be adjusted in consideration of the known bias.1.1 This test method covers the measurement of fabrics that exhibit high stretch and good recovery from low tension. Fabric stretch is measured when a known load is applied. Fabric growth is evaluated after a known extension is applied and subsequently removed.1.2 The procedures for fabric stretch and fabric growth can be used together, or individually.1.3 While this test method can be used for a knit fabric, fabrics intended for support or other applications are better evaluated using other test methods: D3107, D4964, D6614.1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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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4.1 Materials Evaluation—Small single sheet testers were developed to supplement the testing of Epstein specimens for various applications. They are especially appropriate for determining the magnetic properties of samples when insufficient material is available for preparation of an Epstein specimen. Although the small specimen size is attractive, the precision of the small sheet testers is not expected to be as good as that of the test method Test Method A343/A343M. Small sheet testers are frequently used to measure the properties of both fully processed and semiprocessed nonoriented and magnetic lamination steels. Specimens of semiprocessed steels are normally subjected to an appropriate quality development anneal prior to testing. Small sheet testers may also be used to evaluate oriented electrical steels in either the as sheared or stress-relief annealed condition.1.1 This guide covers procedures for interpreting the specific core loss and peak permeability determined using small single-sheet test systems. It is limited to single-sheet test systems that require a test specimen or coupon be cut from the material being tested and are designed such that the entire width of that test specimen is magnetized during testing.1.2 This guide is primarily intended for measurements of the magnetic properties of flat-rolled electrical steels at frequencies of 50 Hz or 60 Hz under sinusoidal flux conditions.1.3 This guide includes procedures to provide correlation with the 25-cm Epstein test method (Test Method A343/A343M).1.4 The range of magnetic flux densities is governed by the properties of the test specimens and the instruments and test power source. Nonoriented electrical steels may be tested at magnetic flux densities up to about 16-kG [1.6T] for core loss. The maximum magnetic field strength for peak permeability testing is limited by the current carrying capacity of the magnetizing winding and the test power source. Single sheet testers are typically capable of testing at magnetic field strengths up to 50 Oe [4000 A/m] or more.1.5 Within this guide, a small single sheet tester (small SST) is defined as a magnetic tester designed to test flat, rectangular sheet-type specimens. Typical specimens for these testers are square (or nearly so). The design of the small SST test fixture may be small enough to accommodate specimens about 5 by 5 cm or may be large enough to accommodate specimens about 36 by 36 cm. Specimens for a particular SST must be appropriate for the particular test fixture.1.6 This guide covers two alternative test methods: Method 1 and Method 2.1.6.1 Method 1 is an extension of Method 1 of Test Method A804/A804M, which describes a test fixture having two windings that encircle the test specimen and two low-reluctance, low-core loss ferromagnetic yokes that serve as flux return paths. The dimensions of the test fixture for Method 1 are not fixed but rather may be designed and built for any nominal specimen dimension within the limits given in 1.5. The power loss in this case is determined by measuring the average value of the product of primary current and induced secondary voltage.1.6.2 Method 2 covers the use of a small single sheet tester, which employs a magnetizing winding, a magnetic flux sensing winding, and a magnetic field strength detector. The power loss in this case is determined by measuring the average value of the product of induced secondary voltage and magnetic field strength.1.6.3 The calibration method described in the annex of this guide applies to both test methods.1.7 The values and equations stated in customary (cgs-emu and inch-pound) or SI units are to be regarded separately as standard. Within this standard, SI units are shown in brackets. 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 nonconformance with this standard.1.8 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.1.9 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 applies to the electrical systems aspects of airworthiness and design for ”small” aircraft. It establishes the Aircraft Type Code (ATC) compliance matrix based on airworthiness level, number of engines, type of engine(s), stall speed, cruise speed, meteorological conditions, altitude, and maneuvers. An ATC is defined by taking into account both the technical considerations regarding the design of the aircraft and the airworthiness level established based upon risk-based criteria. The requirements established by this specification cover power source capacity and distribution, electrical systems and equipment, storage battery design and installation, circuit protective devices, master switch arrangement, switches, electrical cables and equipment, electrical system fire protection, and electronic equipment.1.1 This specification covers electrical systems, electrical equipment, and electrical power distribution aspects of airworthiness and design for aeroplanes with combustion engine generation of electrical power. The material was developed through open consensus of international experts in general aviation. This information was created by focusing on Normal Category Aeroplanes. The content may be more broadly applicable; it is the responsibility of the applicant to substantiate broader applicability as a specific means of compliance.1.2 An applicant intending to propose this information as Means of Compliance for a design approval shall seek guidance from their respective oversight authority (for example, published guidance from applicable civil aviation authorities (CAAs)) concerning the acceptable use and application thereof. For information on which oversight authorities have accepted this specification (in whole or in part) as an acceptable Means of Compliance to their regulatory requirements (hereinafter “the Rules”), refer to ASTM Committee F44 web page (www.astm.org/COMMITTEE/F44.htm). Annex A1 maps the Means of Compliance described in this specification to EASA CS-23, amendment 5, or later, and FAA 14 CFR Part 23, amendment 64, or later.1.3 Units—This standard may present information in either SI units, English Engineering units, or both; the values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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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4.1 This test method is designed to provide a uniform test to assess the suitability of coatings, used in nuclear power facilities, under radiation exposure for the life of the facilities, including radiation during a DBA (Coating Service Level I areas only). Specific plant radiation exposure may exceed or be less than the amount specified in 7.2 of this standard. If required by the licensee design basis, the gamma dose used may exceed the actual anticipated plant gamma dose to account for beta dose. Coatings in Level II and III areas (outside primary containment) are expected to be exposed to lower accumulated radiation doses.1.1 This test method covers a standard procedure for evaluating the lifetime radiation tolerance of coatings to be used in nuclear power plants. This test method is applicable to Coating Service Levels I, II, and III.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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4.1 This practice is intended to help users, particularly power plant operators, maintain effective control over their mineral lubricating oils and lubrication monitoring program. This practice may be used to perform oil changes based on oil condition and test results rather than on the basis of service time or calendar time. It is intended to save operating and maintenance expenses.4.2 This practice is also intended to help users monitor the condition of mineral lubricating oils and guard against excessive component wear, oil degradation, or contamination, thereby minimizing the potential of catastrophic machine problems that are more likely to occur in the absence of such an oil condition monitoring program.4.3 This practice does not necessarily reference all of the current oil testing technologies and is not meant to preclude the use of alternative instrumentation or test methods that provide meaningful or trendable test data, or both. Some oil testing devices and sensors (typically used for screening oils that will be tested according to standard methods) provide trendable indicators that correlate to water, particulates, and other contaminants but do not directly measure these.4.4 This practice is intended for mineral oil products, and not for synthetic type of products, with the exception of phosphate esters fluids typically used in power plant control systems.1.1 This practice covers the requirements for the effective monitoring of mineral oil and phosphate ester fluid lubricating oils in service auxiliary (non-turbine) equipment used for power generation. Auxiliary equipment covered includes gears, hydraulic systems, diesel engines, pumps, compressors, and electrohydraulic control (EHC) systems. It includes sampling and testing schedules and recommended action steps, as well as information on how oils degrade.NOTE 1: Other types of synthetic lubricants are sometimes used but are not addressed in this practice because they represent only a small fraction of the fluids in use. Users of these fluids should consult the manufacturer to determine recommended monitoring practices.1.2 This practice does not cover the monitoring of lubricating oil for steam and gas turbines. Rather, it is intended to complement Practice D4378.1.3 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, 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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3.1 This test method provides a satisfactory means of determining various ac magnetic properties of amorphous magnetic materials.3.2 The procedures described herein are suitable for use by producers and users of magnetic materials for materials specification acceptance and manufacturing control.3.3 The procedures described herein may be adapted for use with specimens of other alloys and other toroidal forms.1.1 This test method covers tests for various magnetic properties of amorphous materials at power frequencies [25 to 400 Hz] using a toroidal test transformer. The term “toroidal test transformer” is used to describe the test device, reserving the term “specimen” to refer to the material used in the test. The test specimen consists of toroidally wound flat strip.1.2 This test method covers the determination of core loss, exciting power, rms and peak exciting current, several types of ac permeability, and related properties under ac magnetization at moderate and high inductions at power frequencies [25 to 70 Hz].1.3 With proper instrumentation and specimen preparation, this test method is acceptable for measurements at frequencies from 5 Hz to 100 kHz. Proper instrumentation implies that all test instruments have the required frequency bandwidth. Also see Annex A2.1.4 This test method also provides procedures for calculating impedance permeability from measured values of rms exciting current and for calculating ac peak permeability from measured peak values of total exciting current at magnetic field strengths up to about 10 Oe [796 A/m].1.5 Explanations of symbols and brief definitions appear in the text of this test method. The official symbols and definitions are listed in Terminology A340.1.6 This test method shall be used in conjunction with Practice A34/A34M.1.7 The values and equations stated in customary (cgs-emu and inch-pound) units or SI units are to be regarded separately as standard. Within this standard, SI units are shown in brackets. 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 nonconformance with this standard.1.8 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.1.9 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 test results enable the comparison of A-weighted sound emission from vacuum cleaners, backpack vacuum cleaners, extractors, or hard-floor cleaning machines when tested under the condition of this test method.1.1 This test method calculates the overall A-weighted sound power level emitted by small portable upright, canister, combination vacuum cleaners, backpack vacuum cleaners, hard-floor cleaning machines, extractors, and central vacuum cleaner motorized nozzles intended for operation in domestic and commercial applications.1.1.1 To determine the Sound Power Level of a central vacuum at the power unit location refer to Test Method F2544.1.2 A-weighted sound pressure measurements are performed on a stationary vacuum cleaner, extractor, hard-floor cleaning machine, or backpack vacuum cleaner in a semi-reverberant room. This test method determines sound power by a comparison method for small noise sources, that is, comparison to a broadband reference sound source.1.3 This test method describes a procedure for determining the approximate A-weighted sound power level of small noise sources. This test method uses a non-special semi-reverberant room.1.4 Results are expressed as A-weighted sound power level in decibels (referenced to one picowatt).1.5 The values stated in inch-pound units are to be regarded as the standard. The values in parentheses are for information only.NOTE 1: The F11.21 subcommittee is actively pursuing new market relevant carpets with the assistance of the carpet industry. Although plush and Freize carpet panels are no longer available for purchase, some laboratories may still have samples for testing. In such cases, the table values remain valid.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.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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4.1 The dielectric breakdown voltage and dielectric strength of an insulating gas in a uniform field depends primarily on the molecular structure of the gas. As different gases are mixed either by plan or by contamination, any change in dielectric breakdown voltage and dielectric strength will depend on both the nature and proportion of the individual gases. This test method uses plane and spherical electrodes which provide a nearly uniform field (see Appendix) in the area of electrical discharge. It is suitable for determining the dielectric breakdown voltage and dielectric strength of different gases and mixtures thereof for research and application evaluations and also as a field test. A more complete discussion of the significance of the dielectric strength test is given in the Appendix.1.1 This test method covers the determination of the dielectric breakdown voltage and dielectric strength of insulating gases used in transformers, circuit breakers, cables, and similar apparatus as an insulating medium. The test method is applicable only to gases with boiling points below room temperature at atmospheric pressure.1.2 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.1.3 Mercury has been designated by 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 and/or mercury containing products into your state may be prohibited by state law.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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3.1 This test method is a fundamental method for evaluating the magnetic performance of flat-rolled magnetic materials in either as-sheared or stress-relief annealed condition.3.2 This test method is suitable for design, specification acceptance, service evaluation, and research and development.1.1 This test method covers tests for the magnetic properties of basic flat-rolled magnetic materials at power frequencies (25 to 400 Hz) using a 25-cm Epstein test frame and the 25-cm double-lap-jointed core. It covers the determination of core loss, rms exciting power, rms and peak exciting current, and several types of ac permeability and related properties of flat-rolled magnetic materials under ac magnetization.1.2 This test method shall be used in conjunction with Practice A34/A34M.1.3 This test method2 provides a test for core loss and exciting current at moderate and high magnetic flux densities up to 15 kG [1.5 T] on nonoriented electrical steels and up to 18 kG [1.8 T] on grain-oriented electrical steels.1.4 The frequency range of this test method is normally that of the commercial power frequencies 50 to 60 Hz. With proper instrumentation, it is also acceptable for measurements at other frequencies from 25 to 400 Hz.1.5 This test method also provides procedures for calculating ac impedance permeability from measured values of rms exciting current and for ac peak permeability from measured peak values of total exciting currents at magnetic field strengths up to about 150 Oe [12 000 A/m].1.6 Explanation of symbols and abbreviated definitions appear in the text of this test method. The official symbols and definitions are listed in Terminology A340.1.7 The values and equations stated in customary (cgs-emu and inch-pound) or SI units are to be regarded separately as standard. Within this standard, SI units are shown in brackets except for the sections concerning calculations where there are separate sections for the respective unit systems. 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 this standard.1.8 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.1.9 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 function and operation of equipment in the field often preclude the measurement of the free-field sound pressure levels of a single piece of equipment in the absence of interfering sound from other equipment operating at the same time. The two-surface method will provide, in most cases, a reliable estimate of the normal sound power levels of a specimen operating in an adverse environment.5.2 This test method is intended for use in the field in the presence of what is normally regarded as interfering background noise. This test method is based upon the work of Hubner 5,6 and Diehl,7 but differs from all other current sound power measurement procedures by requiring simultaneous measurement at both conformal surfaces and by resolving time-averaged sound pressure levels at both surfaces to within 0.1 dB. These two features, simultaneous recording and 0.1dB resolution, enable source sound power to be calculated when the direct sound field of the source is actually lower in level than the ambient noise.5.3 The use of this test method is expected to be primarily for the relative assessment of the sound power from similar sources or for the prediction of sound levels in a plant based upon measurements of similar sources in another plant. This test method is believed to be capable of yielding a reasonably good estimate of absolute power level with proper care of application and full conformance to the provisions of this procedure.5.4 The two-surface method is applicable only when the two measurement surfaces can be physically selected to produce positive values of the difference in average sound pressure level. That is, the inner surface sound pressure level minus the outer surface sound pressure level must be at least +0.1 dB. This limitation applies to each frequency band and each constituent surface area investigated. Only the frequency band in which a zero or negative difference occurs is it considered invalid and usually adjacent bands will be valid. In practice, only rarely will all three one-third octave bands of a given octave yield invalid data at all constituent areas. Therefore, less than complete results are permissible when one-third octave analysis is used and full octave results are reported.5.5 The two-surface method may not produce results when testing some very large machines in very reverberant rooms or in rooms having a volume less than about 20 times the space enclosed by an envelope around the larger dimensions of the machine. In such cases, the sound pressure level close to the machine may not decrease in any regular way with increasing distance from a machine surface, making it impossible to select two measurement surfaces producing positive differences of sound pressure level.1.1 This test method covers the field, or in situ measurement of sound power level by the two-surface method. The test method is designed to minimize the effects of reverberant conditions, directivity of the noise source under consideration, and the effects of ambient noise from other nearby equipment operating at the same time.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 and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 This test method provides a satisfactory means of determining various ac magnetic properties of amorphous magnetic materials. It was developed to supplement the testing of toroidal and Epstein specimens. For testing toroidal specimens of amorphous materials, refer to Test Method A912/A912M.4.2 The procedures described herein are suitable for use by manufacturers and users of amorphous magnetic materials for materials specification acceptance and manufacturing control.NOTE 2: This test method has been principally applied to the magnetic testing of thermally, magnetically annealed, and flattened amorphous strip at 50 and 60 Hz. Specific core loss at 13 or 14 kG [1.3 or 1.4 T], specific exciting power at 13 or 14 kG [1.3 or 1.4 T], and the flux density, B, at 1 Oe [79.6 A/m] are the recommended parameters for evaluating power grade amorphous materials.1.1 This test method covers tests for various magnetic properties of flat-cast amorphous magnetic materials at power frequencies (50 and 60 Hz) using sheet-type specimens in a yoke-type test fixture. It provides for testing using either single- or multiple-layer specimens.NOTE 1: This test method has been applied only at frequencies of 50 and 60 Hz, but with proper instrumentation and application of the principles of testing and calibration embodied in the test method, it is believed to be adaptable to testing at frequencies ranging from 25 to 400 Hz.1.2 This test method provides a test for specific core loss, specific exciting power and ac peak permeability at moderate and high flux densities, but is restricted to very soft magnetic materials with dc coercivities of 0.07 Oe [5.57 A/m] or less.1.3 The test method also provides procedures for calculating ac peak permeability from measured peak values of total exciting currents at magnetic field strengths up to about 2 Oe [159 A/m].1.4 Explanation of symbols and abbreviated definitions appear in the text of this test method. The official symbols and definitions are listed in Terminology A340.1.5 This test method shall be used in conjunction with Practice A34/A34M.1.6 The values stated in either customary (cgs-emu and inch-pound) or SI units are to be regarded separately as standard. Within this standard, SI units are shown in brackets. 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 nonconformance with this 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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5.1 Stray radiant power can be a significant source of error in spectrophotometric measurements. SRP usually increases with the passage of time; therefore, testing should be performed periodically. Moreover, the SRPR test is an excellent indicator of the overall condition of a spectrophotometer. A control-chart record of the results of routinely performed SRPR tests can be a useful indicator of need for corrective action or, at least, of the changing reliability of critical measurements.5.2 This test method provides a means of determining the stray radiant power ratio of a spectrophotometer at selected wavelengths in a spectral range, as determined by the SRP filter used, thereby revealing those wavelength regions where significant photometric errors might occur. It does not provide a means of calculating corrections to indicated absorbance (or transmittance) values. The test method must be used with care and understanding, as erroneous results can occur, especially with respect to some modern grating instruments that incorporate moderately narrow bandpass SRP-blocking filters. This test method does not provide a basis for comparing the performance of different spectrophotometers.NOTE 8: Kaye (3) discusses correction methods of measured transmittances (absorbances) that sometimes can be used if sufficient information on the properties and performance of the instrument can be acquired. See also A1.2.5.5.3 This test method describes the performance of a spectrophotometer in terms of the specific test parameters used. When an analytical sample is measured, absorption by the sample of radiation outside of the nominal bandpass at the analytical wavelength can cause a photometric error, underestimating the transmittance or overestimating the absorbance, and correspondingly underestimating the SRPR.5.4 The SRPR indicated by this test method using SRP filters is almost always an underestimation of the true value (see 1.3). A value cited in a manufacturer’s literature represents the performance of a new instrument, tested exactly in accordance with the manufacturer’s specification. The implication is that the manufacturer’s stated SRPR can serve as a benchmark for future performance, provided that the user performs the manufacturer’s specified test. It is recommended that users test new instruments promptly, thereby establishing a comparative benchmark in terms of their own testing facilities. The solution filter ratio method (4.3) is a convenient method for control-charting SRPR. Mielenz, et al., (4) show that its results tend to correlate well with those of the specified wavelength method, but for critical comparison with the manufacturer’s specification, the method used by the manufacturer must be used. Because some instruments reduce SRP by incorporating moderately narrow bandpass SRP-blocking filters that are changed as the wavelength range is scanned, it is possible for SRPR determinations to be highly inaccurate if the cutoff wavelength of the SRP filter falls too close to the absorption edge of an instrument’s SRP-reducing filter (3).1.1 Stray radiant power (SRP) can be a significant source of error in spectrophotometric measurements, and the danger that such error exists is enhanced because its presence often is not suspected (1-4).2 This test method affords an estimate of the relative radiant power, that is, the Stray Radiant Power Ratio (SRPR), at wavelengths remote from those of the nominal bandpass transmitted through the monochromator of an absorption spectrophotometer. Test-filter materials are described that discriminate between the desired wavelengths and those that contribute most to SRP for conventional commercial spectrophotometers used in the ultraviolet, the visible, the near infrared, and the mid-infrared ranges. These procedures apply to instruments of conventional design, with usual sources, detectors, including array detectors, and optical arrangements. The vacuum ultraviolet and the far infrared present special problems that are not discussed herein.NOTE 1: Research (3) has shown that particular care must be exercised in testing grating spectrophotometers that use moderately narrow bandpass SRP-blocking filters. Accurate calibration of the wavelength scale is critical when testing such instruments. Refer to Practice E275.1.2 These procedures are neither all-inclusive nor infallible. Because of the nature of readily available filter materials, with a few exceptions, the procedures are insensitive to SRP of very short wavelengths in the ultraviolet, or of lower frequencies in the infrared. Sharp cutoff longpass filters are available for testing for shorter wavelength SRP in the visible and the near infrared, and sharp cutoff shortpass filters are available for testing at longer visible wavelengths. The procedures are not necessarily valid for “spike” SRP nor for “nearby SRP.” (See Annexes for general discussion and definitions of these terms.) However, they are adequate in most cases and for typical applications. They do cover instruments using prisms or gratings in either single or double monochromators, and with single and double beam instruments.NOTE 2: Instruments with array detectors are inherently prone to having higher levels of SRP. See Annexes for the use of filters to reduce SRP.1.3 The proportion of SRP (that is, SRPR) encountered with a well-designed monochromator, used in a favorable spectral region, typically is 0.1 % transmittance or better, and with a double monochromator it can be less than 1×10-6, even with a broadband continuum source. Under these conditions, it may be difficult to do more than determine that it falls below a certain level. Because SRP test filters always absorb some of the SRP, and may absorb an appreciable amount if the specified measurement wavelength is not very close to the cutoff wavelength of the SRP filter, this test method underestimates the true SRPR. However, actual measurement sometimes requires special techniques and instrument operating conditions that are not typical of those occurring during use. When absorption measurements with continuum sources are being made, it can be that, owing to the effect of slit width on SRP in a double monochromator, these test procedures may offset in some degree the effect of absorption by the SRP filter; that is, because larger slit widths than normal might be used to admit enough energy to the monochromator to permit evaluation of the SRP, the stray proportion indicated could be greater than would normally be encountered in use (but the net effect is still more likely to be an underestimation of the true SRPR). Whether the indicated SRPR equals or differs from the normal-use value depends on how much the SRP is increased with the wider slits and on how much of the SRP is absorbed by the SRP filter. What must be accepted is that the numerical value obtained for the SRPR is a characteristic of the particular test conditions as well as of the performance of the instrument in normal use. It is an indication of whether high absorbance measurements of a sample are more or less likely to be biased by SRP in the neighborhood of the analytical wavelength where the sample test determination is made.1.4 The principal reason for a test procedure that is not exactly representative of normal operation is that the effects of SRP are “magnified” in sample measurements at high absorbance. It might be necessary to increase sensitivity in some way during the test in order to evaluate the SRP adequately. This can be accomplished by increasing slit width and so obtaining sufficient energy to allow meaningful measurement of the SRP after the monochromatic energy has been removed by the SRP filter. However, some instruments automatically increase sensitivity by increasing dynode voltages of the photomultiplier detector. This is particularly true of high-end double monochromator instruments in their ultraviolet and visible ranges. A further reason for increasing energy or sensitivity can be that many instruments have only absorbance scales, which obviously do not extend to zero transmittance. Even a SRP-proportion as large as 1 % may fall outside the measurement range.NOTE 3: Instruments that have built-in optical attenuators to balance sample absorption may make relatively inaccurate measurements below 10 % transmittance, because of poor attenuator linearity. The spectrophotometer manufacturer should be consulted on how to calibrate transmittance of the attenuator at such lower level of transmittance.1.5 High accuracy in SRP measurement is not always required; a measurement reliable within 10 or 20 % may be sufficient. However, regulatory requirements, or the needs of a particular analysis, may require much higher accuracy. Painstaking measurements are always desirable.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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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