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5.1 Eddy current instrumentation provides timely and useful information regarding the acceptability of copper and aluminum rod for quality control purposes, as well as providing for early warning that unacceptable rod is being produced. Eddy current testing is a nondestructive method of locating surface discontinuities in a product. Signals can be produced by discontinuities located on the surface of the rod. Since the density of eddy currents decreases nearly exponentially as the distance from the surface increases, deep-seated defects may be undetected.5.1.1 An exception is the detection of subsurface ferromagnetic inclusions with an additional, or shared, winding enveloped in a DC magnetic field and the addition of appropriate instrumentation. The coil winding, acting as a transducer, generates a voltage as the magnetized inclusion passes through, providing an electrical signal separate from the eddy current response to surface imperfections. The rod is transparent to the DC effect allowing high sensitivity to ferromagnetic inclusions, in the absence of eddy current noise. The method is inherently speed sensitive but is enhanced by high throughput speeds enabling the detection of small subsurface ferromagnetic inclusions which are particularly detrimental to rod quality.5.2 Some indications obtained by this practice may not be relevant to product quality. For example, a signal may be caused by minute flaws or irregularities, by anomalies in the material, or a combination thereof, that are not detrimental to the end use of the product. Nonrelevant indications, referred to as “noise,” can mask unacceptable discontinuities. On the other hand, relevant indications are those that may result from unacceptable discontinuities and should be determined by agreement between the user and the supplier. Any indication that is believed to be irrelevant shall be regarded as unacceptable until it is demonstrated by reexamination or other means to be nonrelevant.1.1 This practice covers the procedures that shall be followed in electromagnetic (eddy current) examination of copper and aluminum redraw rods for detecting discontinuities or imperfections of a severity likely to cause failure or markedly impair surface quality of the rod. These procedures are applicable for continuous lengths of redraw rod in diameters from 1/4 to 13/8 in. (6.4 to 35 mm) suitable for further fabrication into electrical conductors.1.2 This practice covers redraw rod made from tough-pitch or oxygen-free coppers. It can also be used for other types of copper, such as fire-refined high conductivity rod. It is also appropriate for aluminum and other nonferrous alloys used for electrical purposes.1.3 The procedures described in this practice are based on methods for making use of differential or absolute stationary encircling annular test coil systems.1.4 This practice does not establish acceptance criteria. Acceptance criteria must be established by the using parties.1.5 Units—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.1.6 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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5.1 The purpose of this practice is to describe a procedure for in-line-eddy-current examination of hot cylindrical bars in the range of diameters listed in 1.2 for large and repetitive discontinuities that may form during processing.5.2 The discontinuities in bar product capable of being detected by the electromagnetic method are listed in 1.3.1. The method is capable of detecting surface and some subsurface discontinuities that are typically in the order of 0.030 in. (0.75 mm) and deeper, but some shallower discontinuities might also be found.5.3 Discontinuities that are narrow and deep, but short in length, are readily detectable by both probe and encircling coils because they cause abrupt flux changes. Surface and subsurface discontinuities (if the electromagnetic frequency provides sufficient effective depth of penetration) can be detected by this method.5.3.1 Discontinuities such as scratches or seams that are continuous and uniform for the full length of cut length bars or extend for extensive linear distances in coiled product may not always be detected when encircling coils are used. These are more detectable with probe coils by intercepting the discontinuity in their rotation around the circumference.5.3.2 The orientation and type of coil are important parameters in coil design because they influence the detectability of discontinuities.5.4 The eddy current method is sensitive to metallurgical variations that occur as a result of processing, thus all received signals above the alarm level are not necessarily indicative of defective product.1.1 This practice covers procedures for eddy current examination of hot ferromagnetic bars above the Curie temperature where the product is essentially nonmagnetic, but below 2100 °F (1149 °C).1.2 This practice is intended for use on bar products having diameters of 1/2 in. (12.7 mm) to 8 in. (203 mm) at linear throughput speeds up to 24 000 ft/min (122 m/sec). Larger or smaller diameters may be examined by agreement between the using parties.1.3 The purpose of this practice is to provide a procedure for in-line eddy current examination of bars during processing for the detection of major or gross surface discontinuities.1.3.1 The types of discontinuities capable of being detected are commonly referred to as: slivers, laps, seams, roll-ins (scale, dross, and so forth), and mechanical damage such as scratches, scores, or indentations.1.4 This practice does not establish acceptance criteria. They must be specified by agreement between the using parties.1.5 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.1.6 This practice 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 practice to establish appropriate safety, health, 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.

定价: 515 加购物车

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This practice describes the standard procedures for providing exposure of thermal control materials to a simulated space environment comprising of the major features of vacuum, electromagnetic radiation, charged particle radiation, and temperature control. Broad recommendations relating to spectral reflectance measurements, as well as test parameters and other information that should be reported as an aid in interpreting test results are delineated. Specifications are provided for the vacuum system, solar simulator, charged particle sources, safety precautions, and data interpretation.1.1 This practice describes procedures for providing exposure of thermal control materials to a simulated space environment comprising the major features of vacuum, electromagnetic radiation, charged particle radiation, and temperature control.1.2 Broad recommendations relating to spectral reflectance measurements are made.1.3 Test parameters and other information that should be reported as an aid in interpreting test results are delineated.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Eddy current testing is a nondestructive method of locating discontinuities in a product. Changes in electromagnetic response caused by the presence of discontinuities are detected by the sensor, amplified and modified in order to actuate audio or visual indicating devices, or both, or a mechanical marker. Signals can be caused by outer surface, inner surface, or subsurface discontinuities. The eddy current examination is sensitive to many factors that occur as a result of processing (such as variations in conductivity, chemical composition, permeability, and geometry) as well as other factors not related to the tubing. Thus, all received indications are not necessarily indicative of defective tubing.1.1 This practice2 covers procedures for eddy current examination of seamless and welded tubular products made of relatively low conductivity materials such as titanium, stainless steel, and similar alloys, such as nickel alloys. Austenitic chromium-nickel stainless steels, which are generally considered to be nonmagnetic, are specifically covered as distinguished from the martensitic and ferritic straight chromium stainless steels which are magnetic.1.2 This practice is intended as a guide for eddy current examination of both seamless and welded tubular products using either an encircling coil or a probe-coil technique. Coils and probes are available that can be used inside the tubular product; however, their use is not specifically covered in this document. This type of examination is usually employed only to examine tubing which has been installed such as in a heat exchanger.1.3 This practice covers the examination of tubular products ranging in diameter from 0.125 to 5 in. (3.2 to 127.0 mm) and wall thicknesses from 0.005 to 0.250 in. (0.127 to 6.4 mm).1.4 For examination of aluminum alloy tubular products, see standard Practice E215.1.5 Units—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.1.6 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.

定价: 515 加购物车

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5.1 The method described determines wet density and gravimetric water content by correlating complex impedance measurement data to an empirically developed model. The empirical model is generated by comparing the electrical properties of typical soils encountered in civil construction projects to their wet densities and gravimetric water contents determined by other accepted methods.5.2 The test method described is useful as a rapid, non-destructive technique for determining the in-place total density and gravimetric water content of soil and soil-aggregate mixtures and the determination of dry density.5.3 This method may be used for quality control and acceptance of compacted soil and soil-aggregate mixtures as used in construction and also for research and development. The non-destructive nature allows for repetitive measurements at a single test location and statistical analysis of the results.NOTE 2: The quality of the result produced by this standard test method is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the requirements of Practice D3740 are generally considered capable of competent and objective sampling/testing/inspection, and the like. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluation some of those factors.1.1 This test method covers the procedures for determining in-place properties of non-frozen, unbound soil and soil aggregate mixtures such as total density, gravimetric water content and relative compaction by measuring the intrinsic impedance of the compacted soil.1.1.1 The method and device described in this test method are intended for in-process quality control of earthwork projects. Site or material characterization is not an intended result.1.2 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.2.1 The gravitational system of inch-pound units is used when dealing with inch-pound units. In this system, the pound (lbf) represents a unit of force (weight) while the unit for mass is slugs. The rationalized slug unit is not given in this standard.1.2.2 In the engineering profession, it is customary practice to use, interchangeably, units representing both mass and force, unless dynamic calculations are involved. This implicitly combines two separate systems of units, that is, the absolute system and the gravimetric system. It is undesirable to combine the use of two separate systems within a single standard. The use of balances or scales recording pounds of mass (lbm), or the recording of density in lbm/ft3 should not be regarded as nonconformance with this standard.1.3 All observed and calculated values shall conform to the Guide for Significant Digits and Rounding established in Practice D6026.1.3.1 The procedures used to specify how data is collected, recorded, and calculated in this standard are regarded as industry standard. In addition, they are representative of the significant digits that should generally be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or decrease the number of significant digits of reported data commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in the analysis methods for engineering design.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.NOTE 1: ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility.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 加购物车

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定价: 1290元 / 折扣价: 1149 加购物车

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