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This specification covers standard requirements for chromium-tungsten-molybdenum-vanadium, with or without tantalum, alloy steel plates intended primarily for welded boilers and pressure vessels designed for elevated temperature service. The steel shall be killed and shall conform to the fine austenitic grain size requirements. Heat and product analyses shall conform to the required chemical composition for carbon, manganese, phosphorus, sulfur, silicon, nickel, chromium, molybdenum, vanadium, boron, tantalum, and tungsten. The material shall undergo tensile test and shall conform to the required tensile properties such as tensile strength, yield strength, and elongation.1.1 This specification covers chromium-tungsten-molybdenum-vanadium, with or without tantalum, alloy steel plates intended primarily for welded boilers and pressure vessels designed for elevated temperature service.1.2 Plates are available under this specification in two grades having different alloy contents as follows:Grade NominalChromiumContent, % NominalTungstenContent, % NominalMolybdenumContent, % NominalVanadiumContent, % NominalTantalumContent, %315 3.00 1.50 0.75 0.25 315T 3.00 1.50 0.75 0.25 0.101.3 The maximum thickness of plates is limited only by the capacity of the composition to meet the specified mechanical property requirements.1.4 The specification is expressed in both inch-pound units and in SI units; however, unless the order specifies the applicable “M” specification designation (SI units), the plates are furnished to inch-pound units.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 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.

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This is not a routine test. The values recorded are applicable only to the sewer being tested and at the time of testing.1.1 This practice covers procedures for testing concrete pipe sewer lines, when using the low-pressure air test method to demonstrate the integrity of the installed material and the construction procedures. This practice is used for testing 100 to 600-mm circular concrete pipe sewer lines utilizing gasketed joints.1.2 This practice is also be used as a preliminary test to enable the installer to demonstrate the condition of the line prior to backfill.1.3 This practice is the SI companion to Practice C 924.Note 1—The user of this practice is advised that air test criteria presented in this practice are similar to those in general use. The test and criteria have been used widely and successfully in testing smaller diameter pipe, but additional data are required to confirm the safety and applicability or develop criteria for pipe larger than 600 mm in diameter. Larger pipe will be accepted more conveniently by visual inspection and individual joint testing.Note 2—The user of this practice is advised that no correlation has been found between air loss and water leakage.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 and health practices and determine the applicability of regulatory limitations prior to use (see Section 6, Safety Precautions).

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This specification covers higher strength chromium-molybdenum-tungsten alloy steel forgings intended primarily for use in boilers and pressure vessels for elevated temperature service. Materials shall be manufactured by melting processes, except that the open hearth process shall not be used, and that the molten steel shall be vacuum degassed prior to or during teeming of the ingot. The alloy steels may then be given an intermediate heat treatment such as normalizing and tempering or a subcrititcal anneal prior to rough machining. Heat analysis shall be obtained from samples to ensure chemical composition requirements are met. The steel forgings shall also undergo tension and Charpy impact tests and shall conform to the following required mechanical properties: tensile strength, yield strength, elongation, reduction of area, lateral expansion, minimum average absorbed energy, and minimum single value. Nondestructive examination procedures, such as straight-beam and angle-beam ultrasonic examination, and magnetic particle examination, shall also be executed.1.1 This specification covers chromium-molybdenum-tungsten alloy steel forgings intended primarily for use in boilers and pressure vessels for elevated temperature service.1.1.1 Elevated temperatures are temperatures in the range where creep and stress rupture properties are important for the alloy steels in this specification.1.2 Supplementary requirements are provided both in this specification and in the General Requirements Specification A788/A788M for use when additional testing or inspection is desired. These shall apply only when specified individually by the purchaser in the purchase order or contract.1.3 Unless the order specifies the applicable “M” specification designation, the forgings shall be supplied to the inch-pound units.1.4 The values stated in either inch-pound or SI (metric) units are to be regarded separately as standard. Within the text and tables, 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 nonconformance with the specification.

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4.1 The purpose of this test is to obtain, by means of a specified laboratory procedure, the values of the equilibrium moisture content at higher RH levels ((≈ 95 to 100%). These values are used either as means to characterize the material or as material characteristics needed as input to appropriate computer models that can simulate wetting or drying potential of individual building materials or material assemblies under specified environmental conditions.1.1 This test method specifies a laboratory procedure for the determination of the water retention curve (or moisture storage capacity) of porous building materials at very high relative humidity (RH) levels (≈ 95 to 100% RH) corresponding to the capillary moisture region of the sorption isotherm. This is achieved by using the pressure plate test apparatus. This technique was originally developed to study soil moisture content and eventually had been adapted to building construction materials.1.2 At higher RH levels (≈ 95 to 100% RH) of the sorption isotherm (see Test Method C1498), use of climatic chamber is not an option. This technique uses overpressure to extract water out of the pore structure of porous materials until equilibrium between the moisture content in the specimens and the corresponding overpressure is achieved. Using the pressure plate extractors, equilibrium can only be reached by desorption.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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This specification covers steel castings, general requirements, for pressure-containing parts. The steel shall be made by open-hearth or electric-furnace process, with or without separate refining such as argon-oxygen-decarburization (AOD), unless otherwise designated by the individual specification. Ferritic and martensitic steel shall be cooled after pouring to provide substantially complete transformation of austenite prior to heat treatment to enhance mechanical properties. The material shall conform to the specified chemical composition requirements. An analysis of each heat shall be made by the manufacturer to determine the percentages of the elements specified. The mechanical test methods and definitions are presented in details. One tension test shall be made from each heat, and shall conform to the tensile requirements specified. Test coupons shall be cast from the same heat as the castings represented, except that for investment castings, the test coupons shall be cast in the same type of mold as the castings. After machining, each casting shall be tested under specified hydrostatic shell test pressures in the applicable steel rating for which the casting is designed.1.1 This specification2 covers a group of common requirements that, unless otherwise specified in an individual specification, shall apply to steel castings for pressure-containing parts under each of the following ASTM specifications:  Title of Specification ASTM Designation     Steel Castings, Carbon, Suitable for Fusion Welding, A216/A216M  for High-Temperature Service  Steel Castings, Martensitic Stainless and Alloy, for A217/A217M  Pressure-Containing Parts, Suitable for High-    Temperature Service  Castings, Austenitic, for Pressure-Containing A351/A351M  Parts  Steel Castings, Ferritic and Martensitic, for Pressure- A352/A352M  Containing Parts, Suitable for Low-Temperature    Service  Steel Castings, Alloy, Specially Heat-Treated, for A389/A389M  Pressure-Containing Parts, Suitable for High-    Temperature Service  Steel Castings Suitable for Pressure Service A487/A487MCastings, Iron-Nickel-Chromium and Nickel A990/A990M  Alloys, Specially Controlled for Pressure-Retaining Parts for Corrosive Service  Castings, Austenitic-Ferritic (Duplex) A995/A995M  Stainless Steel, for Pressure-Containing Parts  1.2 This specification also covers a group of supplementary requirements which may be applied to the above specifications as indicated therein. These are provided for use when additional testing or inspection is desired and apply only when specified individually by the purchaser in the order.1.3 In case of conflict between the requirements of the individual specification and this general specification, the former shall prevail.1.4 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.1.5 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 chromium-manganese-silicon alloy steel plates, intended particularly for welded boilers and other pressure vessels.1.2 Plates under this specification are available in two grades having strength levels as follows:Grade Tensile Strengthksi [MPa]A 75-95 [515-655]B 85-110 [585-760]1.3 The maximum thickness of plates is limited only by the capacity of the composition to meet the specified mechanical property requirements; however, current practice normally limits the maximum thickness of plates furnished under this specification to 2 in. [50 mm].1.4 Grade A is suitable for rivets and when so used the bars shall be subject to the requirements for rolled bars specified in Specification A 31, except for the chemical and mechanical requirements.1.5 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 exact equivalents. Therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with this specification.

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1.1 This specification covers minimum-wall-thickness, electric-resistance-welded, carbon steel, boiler and superheater tubes for high-pressure service. 1.2 The tubing sizes and thicknesses usually furnished to this specification are 1/2 in. to 5 in. [12.7 to 127 mm] in outside diameter and 0.085 to 0.360 in. [2.2 to 9.1 mm] inclusive, in minimum wall thickness. Tubing having other dimensions may be furnished, provided such tubes comply with all other requirements of this specification. 1.3 Mechanical property requirements do not apply to tubing smaller than 1/8 in. [3.2 mm] in inside diameter or 0.015 in. [0.4 mm] in thickness. 1.4 When these products are to be used in applications conforming to ISO Recommendations for Boiler Construction, the requirements of Specification A520 shall supplement and supersede the requirements of this specification. 1.5 An optional supplementary requirement is provided and, when desired, shall be so stated in the order. 1.6 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 exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification. The inch-pound units shall apply unless the "M" designation of this specification is specified in the order.

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4.1 This practice describes one method for accelerated weathering of pressure-sensitive tapes used primarily for packaging. It is not intended for evaluation the weathering characteristics of pressure-sensitive tapes used in long-term outdoor exposure conditions (see Practice D5105).4.2 This practice does not necessarily provide direct simulation of natural exposure.4.3 Results from use of this practice shall not be represented as being equivalent to those of any natural weathering test until a satisfactory degree of correlation has been established for the material in question.4.4 Variation in results are possible when operating conditions vary within accepted limits for the instrument specified in Practices G151 and G155.1.1 This practice describes one environment for the exposure of pressure-sensitive tape, used primarily for packaging, to a laboratory accelerated weathering environment.1.2 This practice describes sample preparation and the accelerated environment to which it shall be exposed. It does not specify the length of time of the exposure nor what tests shall be performed on the material following the exposure.1.3 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 non-conformance with 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.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: 515元 / 折扣价: 438 加购物车

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5.1 These test methods provide a field technique for the bacteriological analysis of electronic process waters. The sampling of these waters and subsequent bacteriological analysis may be critical to electronic product yields. Bacteria can be the prime source of harmful contamination which can significantly reduce the yield of satisfactory microelectronic device production.5.2 The test methods described here may be used both to monitor the bacteriological quality of water used in microelectronic product processing, and to locate the source of bacterial contamination in a water purification system.5.3 These test methods are simple field methods, combining sampling and bacteriological analysis techniques that do not require bacteriological laboratory facilities.5.4 The test methods described employ culture techniques for bacteriological analysis. The user should be aware that such techniques cannot provide a complete count of the total viable bacteria present, since clumps and clusters of bacteria will appear as one single colony when cultured, and since some viable bacteria will not grow under the test conditions used. However, a meaningful comparative bacteria count will be achieved by this method if the culturing of the sample is always done at the same temperature, and for the same period of time. The temperature of incubation should always be at 28 ± 2°C, and the period of incubation should be 48 h (or 72 h if time permits). The period of incubation and temperature should be the same for all comparative studies.1.1 These test methods cover sampling and analysis of high purity water from water purification systems and water transmission systems by the direct sampling tap and filtration of the sample collected in the bag. These test methods cover both the sampling of water lines and the subsequent microbiological analysis of the sample by the culture technique. The microorganisms recovered from the water samples and counted on the filters include both aerobes and facultative anaerobes.1.2 Three methods are described as follows:  SectionsTest Method A—Sample Tap—Direct Filtration 6 to 8Test Method B—Presterilized Plastic Bag Technique 9 to 12Test Method B2 —Dip Strip Technique2/Presterilized Plastic Bag  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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1.1 This specification covers crosslinked polyethylene (PEX) pipe that is outside diameter controlled in metric pipe sizes (DN 16 to 1000) and inch pipe sizes (NPS 3 to 54), and pressure rated (see Appendix X1) using the MRS rating system. This Specification is intended for PEX pipe made by various processes, as long as the PEX pipe made by that process meets all the requirements of this Specification. Included are requirements and test methods for material, workmanship, UV protection, dimensions, hydrostatic sustained pressure, stabilizer functionality, bent-pipe hydrostatic pressure, chemical resistance, minimum operating temperature, degree of crosslinking, squeeze-off, and hydrostatic burst pressure. Requirements for pipe markings are also given. The pipe covered by this specification is intended for natural gas distribution.1.2 This specification also includes requirements for qualifying joints made using polyethylene electrofusion fittings (such as Specification F3373) and PEX pipe. Fittings to be used with PEX pipe manufactured to this specification are in Specification F2829/F2829M. Installation considerations are in X3.2.NOTE 1: NPS fittings should not be used for DN sized pipe, and DN sized fittings should not be used for NPS pipe.1.3 The text of this specification references notes, footnotes, and appendixes, which provide explanatory material. These notes and footnotes (excluding those in tables and figures) should not be considered as requirements of the specification.1.4 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 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.1.4.1 For consistency with ISO 9080, MRS values are only in MPa and degrees Centigrade for conversion to the pipe material designation code (for example PEX pipe with an MRS of 8 MPa is called a PEX 80.1.5 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 The values obtained by this test method are applicable only to conditions that specifically duplicate the procedures used.5.2 After a scaling constant is determined for one diameter, this may be used for calculating the external failure pressures of other diameters as long as the resin and reinforcement (if used), the wall thickness-to-diameter ratio, and the reinforcement pattern (if reinforcement is used) are the same.NOTE 3: Based upon tests conducted on one size of pipe, a scaling constant is calculated according to 10.1 or 10.2. The appropriate constant is used to calculate failure pressure for other pipe diameters, but it can only be applied if the same resin and reinforcement are used, the wall thickness to diameter ratios are similar, and the reinforcement pattern is constant.5.3 In the application of the following test requirements and recommendations, care must be exercised to ensure that the specimens tested are truly representative of the group being studied.1.1 This test method covers determination of the resistance of fiberglass pipe to external pressure. It classifies failures as buckling, compressive, and leaking. Both glass-fiber-reinforced thermosetting-resin pipe (RTRP) and glass-fiber-reinforced polymer mortar pipe (RPMP) are fiberglass pipes.NOTE 1: For the purposes of this standard, polymer does not include natural polymers.1.2 The values stated in inch-pound units are to be regarded as standard. The SI units given in parentheses are for information only.NOTE 2: There is no known ISO equivalent to 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.

定价: 515元 / 折扣价: 438 加购物车

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4.1 Pressure-sensitive film tapes are supplied in roll form. For such a tape to be useful a strip of the tape must be easily dispensed or severed from the roll by means of a cutter found on most dispensers. This test method is a means of measuring the ease of this severing or dispensing of the tape.4.2 This test method provides information that can be used in material specifications for product design and quality assurance applications. It can be used in comparing different tape products on specific dispensing blades.4.3 This test method may be suited for office and stationery and tapes with acetate, cellophane, or light-duty plastic backings. Some tapes may be shown to be difficult to dispense under these conditions yet are readily dispensable with other dispensing systems.NOTE 1: Backings described in CID A-A-113 are typical backings.1.1 This test method covers the measurement of the force and elongation required to dispense pressure-sensitive film tape on a 1-in. core intended for office and stationery applications from a desk-top dispenser.1.2 The values stated in either SI or inch-pound units are to be regarded separately as standard. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other.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 This test is meant to simulate the ability of a coating applied to a basement or other below grade masonry walls to prevent the intrusion of water through the coating caused by hydrostatic pressure from water on the outside of the structure.1.1 This practice is for the evaluation of coatings used in below grade applications to resist the passage of water through concrete block.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: 515元 / 折扣价: 438 加购物车

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5.1 Vapor pressure is a fundamental thermophysical property of a liquid. Vapor pressure data are useful in process design and control, in establishing environmental regulations for safe handling and transport, for estimation of volatile organic content (VOC), and in deriving hazard assessments. Vapor pressure and boiling temperature data are required for Safety Data Sheets (SDS). The enthalpy of vaporization may also be estimated from the slope of the vapor pressure curve (see Practice E2071).1.1 This test method describes a procedure for the determination of the vapor pressure of pure liquids or melts from boiling point measurements made using differential thermal analysis (DTA) or differential scanning calorimetry (DSC) instrumentation operated at different applied pressures.1.2 This test method can be used for the temperature range 273 K to 773 K (0 °C to 500 °C) and for pressures between 0.2 kPa to 2 MPa. These ranges may differ depending upon the instrumentation used and the thermal stability of materials tested. Because a range of applied pressures is required by this test method, the analyst is best served by use of instrumentation referred to as high pressure differential thermal instrumentation (HPDSC or HPDTA).1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. (See also IEEE/ASTM SI 10.)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 If required by the authority having jurisdiction, pressurized gaseous testing media leak testing is conducted after installation to discover and correct or repair leaks or faults in a newly constructed or modified PA12 pressure piping system before placing the system in service. Leakage or faults most commonly occur at connections, joints, and mechanical seals where sealing under pressure is required.5.2 Safety is of paramount importance when conducting pressurized gaseous testing media leak tests because testing results include no leaks, leaks, sudden violent rupture, or catastrophic failure.5.3 Systems that contain lower pressure rated or non-pressure rated components that cannot be isolated or removed from exposure to test pressure, or where temporary caps or closures are not practical, are not suitable for testing in accordance with this practice.5.4 Leakage Allowance—Leakage is not allowed for butt and electrofusion joints, and restrained gas-tight mechanical joints. See 7.6. Contact the joint, connection or component manufacturer for leakage correction information if leakage occurs at a joint, connection or component having a mechanical seal.5.5 Poisson-Effect Expansion and Contraction—When test pressure is applied to plastic piping systems that have fully restrained joints such as heat fusion, electrofusion, bolted flanges, etc., either reduction of overall pipe length or an increase in longitudinal stress results from diametrical expansion of the pipe. Disjoining (pull-out) of partially restrained or non-restrained connections or joints, such as some in-line mechanical connectors having insufficient resistance to pull-out stress or length reduction, is possible when partially restrained or unrestrained joints are in-line with the fully restrained test section. To prevent Poisson-effect disjoining of partially restrained or non-restrained joints take measures such as installing external joint restraints (diametrical clamps and tie-rods) on in-line partially restrained or non-restrained joints, installing in-line thrust anchors at the ends of fully restrained piping sections to prevent end movement of the fully restrained section, or isolating a fully restrained test section from piping with unrestrained or partially restrained joints.NOTE 3: A tensile stress applied to a material will cause elongation in the direction of the applied stress, and will cause a decrease in dimension at right angles to the direction of the applied stress. The ratio of decrease to elongation is the Poisson ratio. Under test pressure, piping materials will expand slightly in diameter and contract in length slightly according to the Poisson ratio of the material.1.1 This practice provides information on apparatus, safety, pre-test preparation, and procedures for conducting field tests of polyamide-12 (PA12) pressure piping systems after installation using gaseous testing media such as un-odorized inert non-toxic gas or air, and applying pressure to determine if leaks exist in the system (pneumatic leak testing). This practice applies only to testing to discover leakage. Testing for other purposes such as testing to establish operating pressure is beyond the scope of this practice.1.2 Leak testing with pressurized gaseous testing media shall be used only if one or both of the following conditions exists:1.2.1 The piping system is so designed that it cannot be filled with a liquid, or1.2.2 The piping system service cannot tolerate traces of liquid testing media.1.3 Where hydrostatic testing is specified in contract documents or by the authority having jurisdiction, testing using pressurized gaseous testing media (pneumatic) testing shall not be substituted without the express consent and authorization of the authority having jurisdiction.1.4 Some manufacturers prohibit or restrict testing of their products with pressurized gaseous testing media. Contact component manufacturers for information. Where the manufacturer of a test section component prohibits or restricts testing with pressurized gaseous testing media testing in accordance with this practice shall not be used without the express consent and authorization of the authority having jurisdiction and the component manufacturer.NOTE 1: Components that are not suitable for testing with gaseous testing media may not be suitable for service with pressurized gas.1.5 This practice does not address leak testing using pressurized liquids (hydrostatic testing). For field leak testing using pressurized liquids, consult the manufacturer for guidance.1.6 This practice does not apply to leak testing of non-pressure, negative pressure (vacuum), or non-PA12 (polyamide-12) piping systems.1.7 This practice does not apply to fuel gas piping systems that extend from the point of delivery to the appliance connections. For other than undiluted liquefied petroleum gas (LP-Gas) systems, the point of delivery shall be considered to be the outlet of the service meter assembly or the outlet of the service regulator or service shutoff valve where no meter is provided. For undiluted LP-Gas, the point of delivery shall be considered to be the outlet of the final pressure regulator, exclusive of line gas regulators, in the system. This practice does not apply to LP-Gas systems covered under NFPA 58.1.8 This practice is intended for use with PA12 pressure piping that conveys gaseous media under pressure (compressed gas) if the owner or operator or installer of the line does not have an established leak testing procedure that is acceptable to the authority having jurisdiction.1.9 Warning—Failure during a pressurized gaseous testing media leak test can be extremely violent and dangerous because energy that is applied to compress the gaseous testing media and to pressurize the system will both be suddenly released.NOTE 2: To illustrate the violent hazard of failure, assume a 5 HP compressor is used to raise the test section to test pressure and that it takes 1 h to achieve test pressure. If sudden rupture occurs, energy release may occur in 2 s. Therefore, the horsepower of the energy release would be 5 HP × 1 h × 3600 s/h / 2 s = 9000 HP. Further, if diameter is doubled, energy release is four times greater. For an example test section that is twice the diameter, energy release would be 36 000 HP.1.10 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. Numbered notes and information in parentheses in the text of the practice are non-mandatory information. Table notes are mandatory information.1.11 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.1.12 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 加购物车

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