定价： 345元 / 折扣价： 294 元

定价： 156元 / 折扣价： 133 元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

定价： 345元 / 折扣价： 294 元

定价： 156元 / 折扣价： 133 元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

定价： 481元 / 折扣价： 409 元 加购物车

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

定价： 553元 / 折扣价： 471 元 加购物车

定价： 345元 / 折扣价： 294 元 加购物车

定价： 156元 / 折扣价： 133 元 加购物车

定价： 728元 / 折扣价： 619 元

This specification covers carbon and alloy steel pipe, electric-fusion-welded with filler metal added, fabricated from pressure-vessel-quality plate of several analyses and strength levels and suitable for high-pressure service at high temperatures. Heat treatment may or may not be required to attain the desired mechanical properties. The pipes are classified according to steel grades and are designated in classes according to the type of heat treatment performed in the pipe manufacture, whether the weld is radiographically examined, and whether the pipe has been pressure tested. The steel welds shall be made either manually or automatically by an electric process involving the deposition of filler metal. The welded joints shall have positive reinforcement at the center of each side of the weld. The contour of this reinforcement shall be smooth, and the deposited metal shall be fused smoothly and uniformly into the plate surface. The joints shall undergo tension, bend and pressure tests. Unacceptable surface imperfections shall be removed by grinding or machining. The depression after grinding or machining shall be blended uniformly into the surrounding surface. Repair of weld and base metal defects shall be done by welding.1.1 This specification2 covers carbon and alloy steel pipe, electric-fusion-welded with filler metal added, fabricated from pressure-vessel-quality plate of several analyses and strength levels and suitable for high-pressure service at high temperatures. Heat treatment may or may not be required to attain the desired mechanical properties or to comply with applicable code requirements. Supplementary requirements are provided for use when additional testing or examination is desired.1.2 The specification nominally covers pipe 16 in. [400 mm] in outside diameter and larger with wall thicknesses up to 3 in. [75 mm] inclusive. Pipe having other dimensions may be furnished provided it complies with all other requirements of this specification.1.3 Several grades and classes of pipe are provided.1.3.1 Grade designates the type of plate used as listed in Table 1.1.3.2 Class designates the type of heat treatment performed in the manufacture of the pipe, whether the weld is radiographically examined, and whether the pipe has been pressure tested as listed in 1.3.3.1.3.3 Class designations are as follows (Note 1):Class Heat Treatment on Pipe Radiography, see Section Pressure Test, see Section       10 none none none11 none 9 none12 none 9 8.313 none none 8.320 stress relieved, see 5.3.1 none none21 stress relieved, see 5.3.1 9 none22 stress relieved, see 5.3.1 9 8.323 stress relieved, see 5.3.1 none 8.330 normalized, see 5.3.2 none none31 normalized, see 5.3.2 9 none32 normalized, see 5.3.2 9 8.333 normalized, see 5.3.2 none 8.340 normalized and tempered, see 5.3.3 none none41 normalized and tempered, see 5.3.3 9 none42 normalized and tempered, see 5.3.3 9 8.343 normalized and tempered, see 5.3.3 none 8.350 quenched and tempered, see 5.3.4 none none51 quenched and tempered, see 5.3.4 9 none52 quenched and tempered, see 5.3.4 9 8.353 quenched and tempered, see 5.3.4 none 8.3NOTE 1: Selection of materials should be made with attention to temperature of service. For such guidance, Specification A20/A20M may be consulted.1.4 Optional requirements of a supplementary nature are provided, calling for additional tests and control of repair welding, when desired.1.5 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the 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 non-conformance with the standard. The inch-pound units shall apply unless the “M” designation of this specification is specified in the order.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.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 This test method may be used for material development, quality control, characterization, and design data generation purposes. This test method is intended to be used with ceramics whose strength is 50 MPa (~7 ksi) or greater.4.2 The flexure stress is computed based on simple beam theory with assumptions that the material is isotropic and homogeneous, the moduli of elasticity in tension and compression are identical, and the material is linearly elastic. The average grain size should be no greater than one-fiftieth of the beam thickness. The homogeneity and isotropy assumption in the standard rule out the use of this test for continuous fiber-reinforced ceramics.4.3 Flexural strength of a group of test specimens is influenced by several parameters associated with the test procedure. Such factors include the loading rate, test environment, specimen size, specimen preparation, and test fixtures. Specimen sizes and fixtures were chosen to provide a balance between practical configurations and resulting errors, as discussed in MIL-STD-1942(MR) and Refs (1, 2).4 Specific fixture and specimen configurations were designated in order to permit ready comparison of data without the need for Weibull-size scaling.4.4 The flexural strength of a ceramic material is dependent on both its inherent resistance to fracture and the size and severity of flaws. Variations in these cause a natural scatter in test results for a sample of test specimens. Fractographic analysis of fracture surfaces, although beyond the scope of this standard, is highly recommended for all purposes, especially if the data will be used for design as discussed in MIL-STD-1942(MR) and Refs (2-5) and Practices C1322 and C1239.4.5 The three-point test configuration exposes only a very small portion of the specimen to the maximum stress. Therefore, three-point flexural strengths are likely to be much greater than four-point flexural strengths. Three-point flexure has some advantages. It uses simpler test fixtures, it is easier to adapt to high temperature and fracture toughness testing, and it is sometimes helpful in Weibull statistical studies. However, four-point flexure is preferred and recommended for most characterization purposes.4.6 This method determines the flexural strength at ambient temperature and environmental conditions. The flexural strength under ambient conditions may or may not necessarily be the inert flexural strength.NOTE 7: time dependent effects may be minimized through the use of inert testing atmosphere such as dry nitrogen gas, oil, or vacuum. Alternatively, testing rates faster than specified in this standard may be used. Oxide ceramics, glasses, and ceramics containing boundary phase glass are susceptible to slow crack growth even at room temperature. Water, either in the form of liquid or as humidity in air, can have a significant effect, even at the rates specified in this standard. On the other hand, many ceramics such as boron carbide, silicon carbide, aluminum nitride, and many silicon nitrides have no sensitivity to slow crack growth at room temperature and the flexural strength in laboratory ambient conditions is the inert flexural strength.1.1 This test method covers the determination of flexural strength of advanced ceramic materials at ambient temperature. Four-point-1/4-point and three-point loadings with prescribed spans are the standard as shown in Fig. 1. Rectangular specimens of prescribed cross-section sizes are used with specified features in prescribed specimen-fixture combinations. Test specimens may be 3 by 4 by 45 to 50 mm in size that are tested on 40-mm outer span four-point or three-point fixtures. Alternatively, test specimens and fixture spans half or twice these sizes may be used. The method permits testing of machined or as-fired test specimens. Several options for machining preparation are included: application matched machining, customary procedure, or a specified standard procedure. This method describes the apparatus, specimen requirements, test procedure, calculations, and reporting requirements. The test method is applicable to monolithic or particulate- or whisker-reinforced ceramics. It may also be used for glasses. It is not applicable to continuous fiber-reinforced ceramic composites.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are 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： 646元 / 折扣价： 550 元 加购物车