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4.1 This test method can be used to determine particle size distributions for material specifications, manufacturing control, and research and development work in the particle size range usually encountered in fluidizable cracking catalysts.1.1 This test method covers the determination of particle size distribution of catalyst and catalyst carrier particles using an electroconductive sensing method and is one of several valuable methods for the measurement of particle size.1.2 The range of particle sizes investigated was 20 to 150 μm (see IEEE/ASTM SI 10) equivalent spherical diameter. The technique is capable of measuring particles above and below this range. The instrument used for this method is an electric current path of small dimensions that is modulated by individual particle passage through an aperture, and produces individual pulses of amplitude proportional to the particle volume.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 For ferromagnetic materials, magnetic particle examination is widely specified for the detection of surface and near-surface flaws such as cracks, laps, seams, and linearly oriented nonmetallic inclusions. Such examinations are included as mandatory requirements in some forging standards such as Specifications A508/A508M and A963/A963M.5.2 Use of alternating current as the power source for magnetic particle examination imposes a significant restriction on the detection of subsurface indications, so that the procedure is essentially limited to the finding of flaws that are open to the surface. Attention therefore is drawn to the need to have the component in the finish-machined condition before conducting the magnetic particle examination.5.3 The presence of residual magnetic fields in a component may be undesirable, and an advantage of the use of an ac power source for magnetic particle examination is that an acceptable level of demagnetization can be readily achieved.1.1 This practice covers a procedure for the magnetic particle examination of steel forgings using alternating current as the power source. The procedure will produce consistent results upon which acceptance standards can be based. This practice does not contain acceptance limits or recommended quality levels.1.2 Only alternating 50–60 cycle current shall be used as the electric power source for any of the magnetizing methods.1.3 When subsurface indications are sought in forgings, then dc magnetization in accordance with Practice A275/A275M should be used.1.4 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. 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. Unless the order specifies the applicable “M” specification designation [SI units], the inch-pound units shall be used.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 is intended for use in the laboratory or in the field for evaluating the cleanliness of distillate fuels, and liquid bio fuels. It is not applicable to on or in-line applications.5.2 This test method offers advantage over traditional filtration methods in that it is a precise rapid test, and advantage over visual methods as it is not subjective.5.3 An increase in particle counts can indicate a change in the fuel condition caused by storage or transfer for example.5.4 High levels of particles can cause filter blockages and have a serious impact on the life of pumps, injectors, pistons and other moving parts. Knowledge of particle size in relation to the metallurgy can provide vital information especially if the hardness of particles is also known from other sources.5.5 This test method specifies a minimum requirement for reporting measurements in particle size bands (see A1.1.2). Some specific applications may require measurements in other particle size bands.5.6 Obtaining a representative sample and following the recommended sample and test specimen preparation procedures and timescales is particularly important with particle counting methods. (See Sections 8, 10, 14.1.4 and Note 8.)5.7 This test method can also be used to estimate the total particulate counts excluding free water droplets in aviation turbine fuels by a chemical pretreatment of the fuel. See Appendix X2.1.1 This test method uses a specific automatic particle counter2 (APC) to count and measure the size of dispersed dirt particles, water droplets and other particles, in light and middle distillate fuel, and bio fuels such as biodiesel and biodiesel blends, in the overall range from 4 µm(c) to 100 µm(c) and in the size bands ≥4 µm(c), ≥6 µm(c), and ≥14 µm(c).NOTE 1: ASTM and military specification fuels falling within the scope of this test method include Specifications: D975 grades 1D and 2D, D1655, D3699, D4814 (see 14.1.1.1), D6751, D7467, distillate grades of D396 and D2880, MIL-DTL-83133, and MIL-DTL-16884.NOTE 2: For the purposes of this test method, water droplets are counted as particles, and agglomerated particles are detected and counted as a single larger particle. Dirt includes biological particles. Although the projected area of a particle is measured, this is expressed as the diameter of a sphere for the purposes of this test method.NOTE 3: The notation (c), used with particle sizes, is used to denote that the apparatus has been calibrated in accordance with ISO 11171. Strictly this only applies to particles up to 50 µm.NOTE 4: This test method may be used for particle sizes bands up to 100 µm(c), however the precision has only been determined for the size bands ≥4 µm(c), ≥6 µm(c), and ≥14 µm(c). All measurements are per millilitre.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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4.1 The purpose of this test method is to define a procedure for testing components intended for installation into a high-purity gas distribution system. Application of this test method is expected to yield comparable data among components tested for the purposes of qualification for this installation.4.2 Background Testing—This test method uses background testing to ensure that the system is not contributing particles above a low, acceptable level. This ensures that counts seen are from the test device, not from a contaminated system. The techniques used to obtain background counts do not produce conditions identical to the conditions existing when a test device is in place. It is recommended that the control products be run periodically to see that they give consistent results. These control products should be the lowest particle release products. They will be additional proof that the system is not contributing excess particles during the static, dynamic, or impact portions of the test.4.3 This test method can be used for testing lengths of tubing. The flow criteria will be identical to that indicated for valves. A tubing test would only include the static background, the impact background, and the static and impact portions of the method. A dynamic portion could be added by actuating the upstream pneumatic valve (PV1), thus creating a flow surge to the test length of tubing.1.1 This test method covers gas distribution system components intended for installation into a high-purity gas distribution system.1.1.1 This test method describes a procedure designed to draw statistically significant comparisons of particulate generation performance of valves tested under aggressive conditions.1.1.2 This test method is not intended as a methodology for monitoring on-going particle performance once a particular valve has been tested.1.2 This test method utilizes a condensation nucleus counter (CNC) applied to in-line gas valves typically used in semiconductor applications. It applies to automatic and manual valves of various types (such as diaphragms or bellows), 6.3 through 12.7-mm (1/4 through 1/2-in.) size. For applications of this test method to larger valves, see the table in the appendix.1.2.1 Valves larger than 12.7 mm (1/2 in.) can be tested by this methodology. The test stand must be sized accordingly. Components larger than 12.7 mm (1/2 in.) should be tested while maintaining a Reynolds number of 20 000 to 21 000. This is the Reynolds number for 12.7-mm (1/2-in.) components tested at a velocity of 30.5 m/s (100 ft/s).1.3 Limitations: 1.3.1 This test method is applicable to total particle count greater than the minimum detection limit (MDL) of the condensation nucleus particle counter and does not consider classifying data into various size ranges.1.3.1.1 It is questionable whether significant data can be generated from nondynamic components (such as fittings and short lengths of tubing) to compare, with statistical significance, to the data generated from the spool piece. For this reason, this test method cannot reliably support comparisons between these types of components.1.3.1.2 If detection or classification of particles, or both, in the size range of laser particle counter (LPC) technology is of interest, an LPC can be utilized for testing components. Flow rates, test times, sampling apparatus, and data analysis outlined in this test method do not apply for use with an LPC. Because of these variations, data from CNCs are not comparable to data from LPCs.1.3.2 This test method specifies flow and mechanical stress conditions in excess of those considered typical. These conditions should not exceed those recommended by the manufacturer. Actual performance under normal operating conditions may vary.1.3.3 The test method is limited to nitrogen or clean dry air. Performance with other gases may vary.1.3.4 This test method is intended for use by operators who understand the use of the apparatus at a level equivalent to six months of experience.1.3.5 The appropriate particle counter manufacturer's operating and maintenance manuals should be consulted when using this test method.1.4 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 6, Hazards.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 is intended for use in the laboratory or in the field to evaluate the cleanliness of distillate fuels, and liquid biofuels, such as biodiesel and diesel blends. This specific test method and the precision statement applies to off-line analysis.NOTE 5: These PCMs can be used for high pressure on-line applications as well, however the repeatability (r) and reproducibility (R) for on-line application were not established.5.2 An increase in particulate counts can indicate a change in the fuel condition caused for example by contamination during storage or transfer. Potential causes of particulates formation during storage could be “fuel-degradation products,” as described in Specification D975, Appendix X3.5.3 High levels of particles can cause filter blockages (especially when the particles are close in size to the filter porosity rating) and have a serious impact on the life of pumps, injectors, pistons, and other moving parts. Knowledge of particle size in relation to the metallurgy can provide vital information, especially if the hardness of particles is also known from other sources.5.4 This test method specifies a minimum requirement for reporting measurements in particle size bands (A1.2.1). Some specific applications may require measurements in other particle size bands. The particle count from the test should be carefully interpreted by the user as it can potentially over-state risk of abrasive damage or filter blocking due to counting water droplets as well as hard dirt particles.5.5 In situations where there is a requirement for the calibration of the apparatus to be solely in accordance with ISO 11171, Test Methods D7619, IP 565, or IP 577 may be used.1.1 This test method uses specific particle contamination monitors (PCMs) to count and measure the size of dispersed dirt particles, water droplets and other particulates, in middle distillate fuel, in the overall range from 4 µm to 70 µm and in the size bands ≥4 µm, ≥6 µm, ≥14 µm, and ≥30 µm.NOTE 1: The term particle contamination monitor, as used in this test method, is the same as that defined in ISO 21018-4; an instrument that automatically measures the concentrations of particles suspended in a fluid at certain sizes and cannot be calibrated in accordance with ISO 11171 whose output may be as a particle size distribution at limited sizes or as a contamination code.1.2 This test method has interim repeatability precision only, see Section 14 for more information.NOTE 2: ASTM specification fuels falling within the scope of this test method include Specifications: D975, D1655, D3699, D7467, MIL-DTL-83133, MIL-DTL-5624, and distillate grades of D396 and D2880.NOTE 3: For the purposes of this test method, water droplets are counted as particles, and agglomerated particles are detected and counted as a single larger particle. Dirt includes microbial particulates. Although the projected area of a particle is measured, this is expressed as the diameter of a circle for the purposes of this test method. The detector is unable to distinguish between dirt and water particles.NOTE 4: This test method may be used for particle sizes bands up to 70 µm, however the interim repeatability has only been determined for the size bands ≥4 µm, ≥6 µm, and ≥14 µm. All measurements are counts per millilitre.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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1.1 This practice covers procedures for adjusting the size ranges of an airborne discrete particle counter (DPC) to match size/concentration data from a reference DPC that has been calibrated for counting and sizing accuracy in accordance with Practice F 328 and is kept in good working order. The practice is applied in situations where time, capabilities, or both, required for carrying out procedures in Practice F 328 are not available. It is particularly useful where more than one DPC may be required to observe an environment where the particulate material being counted and sized is different in composition from the precision spherical particulate materials used for calibration in Practice F 328 and/or all of the DPCs in use are not similar in optical or electronic design.1.2 Procedures covered here include those to measure sampled and observed air volume or flow rate, zero count level, particle sizing and counting accuracy, particle sizing resolution, particle counting efficiency, and particle concentration limit.

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ASTM E2651-19 Standard Guide for Powder Particle Size Analysis Active 发布日期 :  1970-01-01 实施日期 : 

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