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1.1 This specification covers iron-copper-tin-graphite sintered metal powder oil-impregnated bearings of one composition commonly known as diluted bronze.1.2 The following safety hazards caveat pertains only to the test method described in this specification: 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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The volume of an arbitrary P/M shape cannot be accurately measured by standard techniques such as by micrometers or calipers. Since density is mass/volume, a precise method to measure the volume is needed. For nonporous objects, the volume of water displaced by the immersed object is determined by Archimedes principle. For porous P/M parts, a method is required to seal surface connected pores. If the pores are not sealed or the part is not oil impregnated, the part will absorb some of the water and decrease its buoyancy and exhibit an erroneously high density.Density and oil content values are generally contained in the specifications for oil-impregnated bearings and other self-lubricating P/M parts. Desired lubrication requires sufficient interconnected porosity and satisfactory oil impregnation of the porosity.For a particular P/M material, the mechanical properties of P/M structural parts are directly related to their density. Density values are therefore generally contained in the specifications for P/M parts.1.1 This test method covers determination of the density, oil content, and interconnected porosity of sintered bearings and structural parts with or without oil impregnation.1.2 The values stated in SI units are to be regarded as the standard. The values 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 and health practices and determine the applicability of regulatory limitations prior to use.

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Moisture has an adverse effect on the dielectric strength, dielectric loss, dc resistivity, and aging characteristics of oil-impregnated cellulosic insulating materials.When cellulosic insulation such as paper and pressboard are impregnated with and immersed in oil, there is an interchange of moisture between the cellulose and oil until they attain equilibrium with respect to their relative saturations with moisture.Considerable care should be taken in using these test methods to measure the water content of dry (<0.5 %) paper and board. Contamination of material by water from the surroundings during sampling and handling may be both rapid and significant in the case of dry test specimens. This is an even greater concern with cellulose insulation prior to oil impregnation.1.1 These test methods cover the determination of the weight percent of water in new or aged, oil-impregnated electrical insulation. These test methods depend on solvent extraction of the water at room temperature. The range from 0.1 to 7.0% water has been explored.1.2 There are four test methods, A, B, C, and D. Methods A and B for thin paper and dense materials, respectively, are manual methods for solvent extraction of water from the specimens. Titration is used to determine the amount of water. Method C uses automatic titration to determine the amount of water. Method D is a direct automated method for extraction and detection of the water.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 and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 This practice defines a procedure that ensures reasonably consistent preparation of specimens for product testing and evaluation.4.2 This practice can be used in the laboratories of producers, users, and general interest parties for research and development or quality control work. It is particularly useful for interlaboratory comparisons on products, for repetitive evaluations or comparisons of products or product quality, and in specifying a uniform preparation practice for specimens for acceptance testing.4.3 If pitch-impregnated samples are prepared by wet cutting or drilling, care should be taken in drying them. If the samples are heated to facilitate drying, the temperature to which they are heated should not be so high that it causes drainage of pitch from the samples.4.4 Porosities of metal-containing brick must be measured using kerosene or mineral spirits, because using water will result in an artificially low result.1.1 This practice covers a procedure for preparing test specimens from magnesia-carbon and impregnated burned basic brick. This practice generally concerns preparation of test specimens from brick greater than 13 in. (33 cm) in length. These brick are mainly manufactured for use in electric arc furnaces and basic oxygen furnaces.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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1. Scope and Purpose 1.0.1 These specifications apply to impregnated paper- insulated, metallic-sheathed cable of the "solid" type which is to be used for the transmission and distribution of electrical energy on electric utility systems. 1.0.2 The

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5.1 This practice may be used to determine if a pre-saturated or impregnated towelette demonstrates antimicrobial effectiveness as a disinfectant on hard surfaces. This practice provides survivor results in the form of a qualitative endpoint (growth positive versus growth negative). The results generated by following this practice do not provide for specific quantitative reductions.1.1 This practice is designed to evaluate the antimicrobial activity of pre-saturated or impregnated towelettes when used as a hard surface disinfectant.1.2 It is the responsibility of the investigator to determine whether Good Laboratory Practices (GLP’s) are required and to follow them when appropriate.1.3 This practice should be performed only by those trained in microbiological techniques.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 Appropriate modifications to the practice may be required when testing organisms not specified herein.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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This specification covers sintered bronze, oil-impregnated bearings made primarily from elemental copper, tin, lead, and graphite powders. This specification covers the following variables: Grades (available in three bronze base compositions identifiable by different graphite contents and one leaded bronze grade) and Type (Grades 1 and 2 are available in four types described by specific density ranges. Grade 3 is available in two types and Grade 4 is available in one type). Sintered bronze bearings shall be made by molding or briquetting metal powder mixtures to the proper density. The material shall conform to the required chemical composition for copper, tin, graphite, iron, lead, zinc, nickel, and antimony. The density of bearings supplied impregnated with lubricant shall be within the prescribed limits. Oil content of bearings shall not be less than the prescribed value for each grade and type of material. The material of different grades and types shall conform to the prescribed radial crushing strength requirements. An acceptance specification for the minimum bearing breaking load may be established for any specific standard oil-impregnated bearing. Chemical analysis shall be made for each representative sample of chips, which may be obtained by milling, drilling, filing, or crushing a bearing with clean dry tools without lubrication.1.1 This specification covers porous metallic sleeve, flange, thrust, and spherical bronze-base bearings that are produced from mixed metal powders utilizing powder metallurgy (PM) technology and then impregnated with oil to supply operating lubrication.1.2 Included are the specifications for the chemical, physical, and mechanical requirements of those bronze-base PM materials that have been developed and standardized specifically for use in the manufacture of these self-lubricating bearings.1.3 This specification is applicable to the purchase of bronze-base bearings (oil-impregnated) that were formerly covered by military specifications and are intended for government or military applications. Those additional government requirements that only apply to military bearings are listed in the Supplementary Requirements section of this specification.1.4 This specification accompanies Specification B439 that covers the requirements for Iron-Base Powder Metallurgy (PM) Bearings, (Oil-Impregnated).1.5 Typical applications for bronze-base bearings are listed in Appendix X1.1.6 Bearing dimensional tolerance data are shown in Appendix X2, while engineering information regarding installation and operating parameters of PM bearings is included in Appendix X3. Additional useful information on self-lubricating bearings can be found in MPIF Standard 35, ISO 5755 and the technical literature.21.7 With the exception of the values for density and the mass used to determine density, for which the use of the gram per cubic centimetre (g/cm3) and gram (g) units is the industry standard, 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.1.8 The following safety hazards caveat pertains only to the test methods described in this specification. 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 covers the standard requirements for porous metallic sleeve, flange, thrust, and spherical iron-base bearings that are produced from mixed metal powder metallurgy technology and then impregnated with oil to supply operating lubrication. Porous iron-base bearings shall be produced by compaction of a mixture of elemental iron powder and copper, tin, pre-alloyed bronze or graphite powders and sintering in a furnace having a protective atmosphere at a specified time and temperature cycle. The interconnected or open porosity in the bearings shall be filled to the required volume either by an extended soaking in hot oil or preferably by a vacuum impregnation operation with lubricating oil which is a high-grade turbine oil with antifoaming additives and containing corrosion and oxidation inhibitors. Each of the iron-base bearing material shall conform to the chemical composition requirements for iron, carbon, graphite, copper, and tin as shall be determined by chemical analysis. The physical properties for each of the bearing material shall be within the prescribed wet density, oil content, and impregnation efficiency limits. The radial crushing strength and bearing breaking load of the oil-impregnated bearing material determined on a plain sleeve bearing or a test specimen prepared from a flange or spherical bearing shall also meet the minimum and maximum mechanical strength values.1.1 This specification covers the requirements for porous iron-base metallic sleeve, flange, thrust, and spherical bearings that are produced from metal powders utilizing powder metallurgy (PM) technology and then impregnated with oil to supply operating lubrication.1.2 Listed are the chemical, physical, and mechanical specifications for those standardized ferrous PM materials that have been developed specifically for the manufacture of self-lubricating bearings.1.3 This specification is a companion to Specification B438 that covers the requirements for porous oil-impregnated bronze-base bearings.1.4 Typical applications for self-lubricating iron-base PM bearings are discussed in Appendix X1.1.5 Commercial bearing dimensional tolerance data are shown in Appendix X2, while engineering information regarding installation and operating parameters of PM bearings is included in Appendix X3. Additional useful information on self-lubricating bearings can be found in MPIF Standard 35 (Bearings), ISO 5755, and the technical literature.21.6 Units—With the exception of the values for density and the mass used to determine density, for which the use of the gram per cubic centimetre (g/cm3) and gram (g) units is the long-standing practice of the PM industry, 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 to be regarded as standard.1.7 The following safety hazards caveat pertains only to the test methods described in this specification. 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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4.1 This practice is for use by designers and specifiers, regulatory agencies, owners, and inspection organizations who are involved in the rehabilitation of conduits through the use of a resin-impregnated tube inverted through the existing conduit. As for any practice, modifications may be required for specific job conditions.1.1 This practice describes the procedures for the reconstruction of pipelines and conduits (2 in. to 108 in. diameter) by the installation of a resin-impregnated, flexible tube which is inverted into the existing conduit by use of a hydrostatic head or air pressure. The resin is cured by circulating hot water, introducing controlled steam within the tube, or by photoinitiated reaction. When cured, the finished pipe will be continuous and tight-fitting. This reconstruction process is used in a variety of gravity and pressure applications such as sanitary sewers, storm sewers, process piping, electrical conduits, and ventilation systems.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 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the 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. For specific precautionary statements, see 7.4.2.1.5 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 specification covers iron-base sintered metal powder, oil-impregnated bearings. There are two grades, depending on the level of combined carbon (see Table 1): 1.1.1 Grade 1, Iron Graphite -low combined carbon, and 1.1.2 Grade 2, Iron Graphite -high combined carbon. 1.2 The values stated in inch-pound units are the standard. The metric equivalents of inch-pound units may be approximate. Note 1--Definitions of powder metallurgy terms can be found in Definitions B243. Additional useful information is available in the Related Material section of Vol 02.05 of the Annual Book of ASTM Standards .Note 2--Information on design, permissible loads, dimensional tolerances, and recommended press fits and running clearances are provided in Appendix X1.

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5.1 The Molten Salt Reactor is a nuclear reactor which uses graphite as reflector and structural material, and molten salt as coolant. The graphite components will be submerged in the molten salt during the lifetime of the reactor. The porous structure of graphite may lead to molten salt permeation, which can affect the thermal and mechanical properties of graphite. Consequently, it may be necessary to measure the various strengths of the manufactured graphite materials after impregnation with molten salt and before exposure to the reactor environment in a range of test configurations in order for designers or operators to assess their performance.NOTE 1: Depending upon the salt selected for the reactor, there may be some chemical reaction between the salt and the graphite that could affect properties. The user should establish, prior to following this guide, that any interactions between the molten salt and graphite are understood and any implications for the validity of the strength tests have been assessed.5.2 For gas-cooled reactors, the strength of a graphite specimen is usually measured at room temperature. However, for molten salt reactors, the operating temperature of the reactor must be higher than the melting temperature of the salt, and so the salt will be in solid state at room temperature. Consequently, room temperature measurements may not be representative of the performance of the material at its true operating conditions. It is therefore necessary to measure the strength at an elevated temperature where the salt is in liquid form.NOTE 2: Users should be aware that a small increase in graphite strength is expected with increasing temperature. Testing at the plant operating temperature will eliminate this small uncertainty.5.3 The purpose of this guide is to provide considerations, which should be included in testing graphite specimens impregnated with molten salt at elevated temperature.5.4 For the test results to be meaningful, the test material must have been impregnated at the reactor operating temperature of interest and the strength measurement conducted at the same temperature following this guide. The user must consider the effect of interaction between graphite and impregnated salt on the representativeness of the strength test based upon the heating and cooling stages between impregnation and testing.NOTE 3: The user may wish to measure the strength of the same test geometry on unimpregnated graphite both at room temperature and at the chosen elevated temperature as a benchmark prior to the testing of the impregnated material.NOTE 4: The user may wish to demonstrate that the impregnated test specimen does not lose molten salt during the elevated strength test procedure. This should be performed by putting the impregnated specimen through the exact procedure (temperature and duration) without applying any test load, weighing the specimen before and after the procedure. A reduction in mass will indicate loss of molten salt and the user will then need to assess its significance.1.1 This guide covers the best practice for strength measurements at elevated temperature of graphite impregnated with molten salt.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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