5.1 Absolute and comparative methods provide a means for sorting large quantities of ferrous parts of stock with regard to composition, condition, structure, or processing, or a combination thereof.5.2 The comparative or two-coil method is used when high-sensitivity testing is required. The advantage of this method is that it almost completely suppresses all internal or external disturbances such as temperature variations or stray magnetic fields, provided both the coils and both the reference parts are exposed to the same conditions which are not of relevance.5.3 The ability to accomplish satisfactorily these types of separations is dependent upon the relation of the magnetic characteristics of the ferromagnetic parts to their physical condition.5.4 These methods may be used for high-speed sorting in a fully automated setup where the speed of testing may approach ten specimens per second depending on their size and shape.5.5 The success of sorting ferromagnetic material depends mainly on the proper selection of magnetic field strength and frequency of signal in the test coil, fill factor, and variables present in the sample.5.6 The degree of accuracy of a sort will be affected greatly by the coupling between the test coil field and the test specimen and the accuracy with which the specimen is held in the test coil field during the measuring period. Testing with harmonics can, to a large extent, reduce the sensitivity to accuracy of location.5.7 When high currents are used in the test coil, a means should be provided to maintain a constant temperature of the reference standard in order to minimize measurement drift.1.1 This practice covers the procedure for sorting ferrous metals using the electromagnetic (eddy current/magnetic induction) method. The procedure relates to instruments using absolute or comparator-type coils for distinguishing variations in mass, shape, conductivity, permeability, and other variables such as hardness and alloy that affect the electromagnetic or magnetic properties of the material. The selection of reference standards to determine sorting feasibility and to establish standards is also included.21.2 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.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 元 加购物车

5.1 Joints in concrete pavements of highways, airfields, and other facilities are exposed to stresses and strains due to traffic and temperature variation. Examining concrete pavement dowel bars (see Specifications A615/A615M and A1078/A1078M) in joints is important to ensure that load transfer at joints between concrete slabs occurs efficiently in order to prevent damage to the pavement and thus shortening its service life. Using magnetic pulse induction (MPI) to examine dowel bars provides owners and contractors a nondestructive testing method to determine that the bars are installed correctly. MPI examination can be performed on existing joints and can support forensic investigations into pavement failures.5.2 The use of MPI methods and equipment provides a quality control process for installers to use to document that dowel bars are installed correctly in new pavements. Owners use the same device to perform quality assurance activities and accept installed facilities from contractors.5.3 MPI devices provide reliable quantitative results that are repeatable with not only the same device but also with other calibrated MPI devices.1.1 This test method covers the equipment, field procedures, and interpretation methods for the assessment of portland cement concrete pavement dowel bar alignment using magnetic pulse induction (MPI), also referred to as magnetic imaging tomography or eddy current tomography. Magnetic pulse induction (MPI) devices induce a weak-pulsed magnetic field that causes the induction of eddy currents in metal objects disturbing the field. When metal (dowel bar) enters into the field, an electrical signal is produced and processed through algorithms to detect and produce quantitative values for the depth, alignment, and side shift locations of each dowel and tie bar present in the pavement joint.1.2 MPI equipment includes the following: systems scanning device that induces the magnetic field and collects the electrical signal; orientation system such as a rail system; field data collection device that collects the signal data from the scanner, performs field analysis, and stores data; analysis software package that calculates the dowel bar positions, allows data adjustments to account for detected anomalies, and produces reports.1.3 MPI field procedures describe the steps and processes required to collect reliable, repeatable, and accurate results from the scanner operation and orientation system. Critical to the accuracy is the absence of any metal items except for the dowel bars in the vicinity of the joints being tested. Metal in the scanner and orientation system should be minimized. The scanner operation procedures cover the collecting of the data, reviewing the results on the field data collector, and determining if the data collection test was successful.1.4 MPI interpretation methods describe how to analyze data collected in the field procedure, steps taken to address interferences, and anomalies discovered during the data analysis to provide accurate results for the dowel bar positions. Also, minimum report content is prescribed for the production of meaningful test information substantiating the results.1.5 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.1.6 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： 590元 / 折扣价： 502 元 加购物车

5.1 The oxidative induction time is a characteristic of a compounded polyolefin product that is dependent not only on the type and amount of additives present, but also on the type of resin. In well-behaved systems, this test method can be used as a quality control measure to monitor the stabilization in geosynthetics as received from a supplier.5.2 When this test method is used to compare different geomembrane formulations containing different antioxidant packages, then those results shall be considered valid only at the temperature of test.5.3 This test method is intended as a geosynthetic test. Use of the OIT value to estimate the lifetime of the geomembrane from which the test specimen is taken is not addressed, nor shall it be used for this purpose.5.3.1 Caution should be exercised in data interpretation since oxidation reaction kinetics are a function of temperature and the properties of the additives contained in the geosynthetic sample. For example, OIT values are often used to select optimum resin formulations. Certain antioxidants, however, may generate poor OIT results even though they may be adequate at their intended use temperature and vice versa.5.4 This test method can be used for other purposes such as manufacturing control and research and development.5.5 Oxidation induction time is strongly dependent upon test temperature and the partial pressure of oxygen. The higher the test temperature or the oxygen partial pressure, or both, the shorter the oxidation induction time.5.5.1 The use of high test temperature, however, may have deleterious effects. The first of these is the potential volatilization of additive packages used to stabilize the test materials. The second is the potential for the influence of chemical mechanisms which are not significant at end-use operation conditions.5.5.2 This test method uses high oxygen pressure to accelerate the test period while making use of lower test temperatures to protect additive packages.5.6 The results from this test method may or may not correlate with those obtained by other OIT measurements such as Test Method D3895, D8117, or D4565.1.1 This test method covers a procedure for the determination of the oxidative induction time (OIT) of polyolefin geosynthetics using high-pressure differential scanning calorimetry.1.2 The focus of the test is on geomembranes, but geogrids, geonets, geotextiles, and other polyolefin-related geosynthetics are also suitable for such evaluation.1.3 This test method measures the oxidative induction time associated with a given test specimen at a specified temperature and pressure.1.4 This is an accelerated test for highly stabilized materials. It is applicable only to material whose OIT values under 3.4 MPa of oxygen are greater than 30 min at 150 °C.1.5 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.1.6 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. Specific precautionary statements are given in Section 8.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

定价： 156元 / 折扣价： 133 元 加购物车

1.1 This specification covers nominal-wall-thickness tubes intended for use as steam surface condenser tubes. These tubes are made from the austenitic steels listed in Table 1 using a high-frequency induction welding process where post-weld solution heat treatment is not necessary for corrosion resistance. 1.2 The tubing sizes and thickness usually furnished to this specification are 5/8 in. (15.9 mm) to 3 1/8 in. (79.4 mm) in outside diameter and 0.015 to 0.109 in. (0.40 to 2.8 mm), inclusive, in wall thickness. Tubing having other dimensions may be furnished, provided such tubes comply with all other requirements of this specification. 1.3 Optional supplementary requirements are provided in this specification and, when one or more of these are desired, each shall be so stated in the order. 1.4 The values stated in inch-pound units are to be regarded as the standard.

定价： 0元 / 折扣价： 0 元

定价： 156元 / 折扣价： 133 元 加购物车

定价： 156元 / 折扣价： 133 元 加购物车

4.1 Oxidation induction time, as determined under the conditions of this test method, may be used as an indication of oxidation stability.2 This test method is faster than other oil oxidation tests and requires a very small amount of sample. It may be used for research and development, quality control, and specification purposes. However, no correlation has been established between the results of this test method and service performance.1.1 This test method covers the determination of oxidation induction time of lubricating oils subjected to oxygen at 3.5 MPa (500 psig) and temperatures between 130 °C and 210 °C.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.2.1 Exception—Pressure measurement appears in MPa with psig provided in parentheses for information only.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 元 加购物车