5.1 Sulfate-reducing bacteria are widely distributed in marine and fresh water muds which, in consequence, frequently are laden with the hydrogen sulfide produced by these organisms during dissimilatory sulfate reduction.5.2 It has been reported that Desulfovibrio spp. can form as much as 10 g of sulfide per litre during active multiplication. Sulfate-reducing bacteria can cause the external or internal corrosion of water or wastewater pipelines and pipelines for petroleum and natural gas. The formation of galvanic cells by massive growth of sulfate-reducing bacteria under suitable conditions makes the corrosion much worse than just the effect of the hydrogen sulfide on the metal or concrete.1.1 These test methods cover the procedure for the detection and enumeration by the most probable number (MPN) technique of sulfate-reducing bacteria in water or water-formed deposits.1.2 Two media preparations are provided. Medium A which is prepared with reagent grade water, and Medium B which is prepared using the water to be sampled as the water source. Medium B is offered for those special conditions where sulfate-reducing bacterial strains have adapted to atypical non-fresh water environment.1.3 For the isolation and enumeration of thermophilic sulfate-reducing bacteria encountered in waters associated with oil and gas production, all broths, dilution blanks, and incubations must be maintained at temperatures of at least 45°C and preferably within 5°C at the sample temperature.1.4 The sensitivity of these test methods can be increased by purging the dilution blanks and tubes of media with nitrogen immediately prior to use.1.5 The analyst should be aware that adequate collaborative data for precision and bias statements as required by Practice D2777 are not provided. See Section 11 for details.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 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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This specification establishes the construction, coding, and performance requirements for self-contained, globe style, pressure-reducing valves used in water systems of shipboard installations that are limited to discharge pressure settings of 200 psig (1379 kPa) and below. The valves shall be either the pressurized spring chamber type (Type I) or unpressurized spring chamber type (Type II). They shall be tested for their conformance with hydrostatic proof, seat tightness, set pressure limits, and capacity.1.1 This specification covers self-contained, globe style, pressure-reducing valves for use in water systems of shipboard installations. These valves are limited to discharge pressure settings of 200 psig (1379 kPa) and below.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 following precautionary caveat pertains only to the tests portion, Section 8, of 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.1.4 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

This specification covers the pre-treatment procedures of iron or steel for reducing the susceptibility or degree thereof to hydrogen embrittlement or degradation that may arise in electroplating, autocatalytic plating, porcelain enameling, chemical conversion coating, and phosphating.1.1 This specification covers procedures for reducing the susceptibility or degree of susceptibility to hydrogen embrittlement or degradation that may arise in electroplating, autocatalytic plating, porcelain enameling, chemical conversion coating, and phosphating and the associated pretreatment processes. This specification is applicable to those steels whose properties are not affected adversely by baking at 190 °C to 230 °C or higher (see 6.1.1).1.2 The heat treatment procedures established herein have been shown to be effective for reducing the susceptibility of steel parts of tensile strength 1000 MPa or greater that have been machined, ground, cold-formed, or cold-straightened subsequent to heat treatment. This heat-treatment procedure is used prior to any operation capable of hydrogen charging the parts, such as the cleaning procedures prior to electroplating, autocatalytic plating, porcelain enameling, and other chemical coating operations.NOTE 1: 1 MPa = 145.1 psi.1.3 This specification has been coordinated with ISO/DIS 9587 and is technically equivalent.1.4 The values stated in SI units are to be regarded as the standard.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.

定价： 515元 / 折扣价： 438 元 加购物车

This guide covers the standard procedure of performing post-coating heat treatment of some steels for reducing susceptibility to hydrogen embrittlement or degradation that may arise in the finishing processes. This heat treatment procedure shall be used after plating operations but prior to any secondary conversion coating operation. Except for surface-hardened and shot-peened parts, the choice of embrittlement-relief heat treatment and the corresponding treatment conditions shall be selected on the basis of actual tensile strength of the steel.1.1 This guide covers procedures for reducing the susceptibility in some steels to hydrogen embrittlement or degradation that may arise in the finishing processes.1.2 The heat treatment procedures established herein may be effective for reducing susceptibility to hydrogen embrittlement. This heat-treatment procedure shall be used after plating operations but prior to any secondary conversion coating operation.1.3 This guide has been coordinated with ISO/DIS 9588 and is technically equivalent.NOTE 1: The heat treatment does not guarantee complete freedom from the adverse effects of hydrogen degradation.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 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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This specification covers the design, construction, testing and operating requirements for pressure-reducing manifolds for air or nitrogen systems, which constitute the combination of all components and piping between, and including, the inlet and outlet ports. The manufactured manifolds shall perform satisfactorily to the following procedures: visual examination; hydrostatic shell test; relief-valve lift test; seat tightness test; and external leakage test.1.1 This specification covers the design, construction, testing and operating requirements for pressure-reducing manifolds for air or nitrogen systems, referred to herein also as manifolds. The term manifold constitutes the combination of all components and piping between, and including, the inlet and outlet ports (see Fig. 1 and Fig. 2).FIG. 1 Manifold ConfigurationFIG. 2 Manifold Configuration1.2 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 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 PDF includes Update No. 2 and Update No. 3 1. Scope 1.1 This Standard applies to devices that automatically reduce the initial pressure to a set lower pressure in water systems and are self-acting spring-operated devices. It applies to devices

定价： 364元 / 折扣价： 310 元

5.1 Hand hygiene is considered one of the most important measures for preventing the spread of infectious microorganisms and is critical for reducing the incidence of food-borne disease. Food-handling settings are unique in that moderate to heavy soil load present on hands often can influence the ability of a product to remove or kill microorganisms (3, 4). Test methods are needed for assessing the efficacy of hand hygiene products under conditions representative of those encountered in a food-handling environment.5.2 This test method is specifically designed to evaluate the effectiveness of food-handler products to kill and remove bacteria from experimentally-contaminated hands under conditions of moderate to heavy organic soil load. The inclusion of soils typical of food service setting makes this a methodology more appropriate than Test Method E1174, which was designed to evaluate healthcare personnel hand washes and does not include an option to include soil (4).1.1 This test method is designed to determine the activity of food-handler handwashes against transient bacterial flora on the hands.1.2 Performance of this procedure requires the knowledge of regulations pertaining to the protection of human subjects (1)2.1.3 This test method should be performed by persons with training in microbiology, in facilities designed and equipped for work with potentially infectious agents at biosafety level 2 (2).1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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. For more specific precautionary statements see 8.1.1.1.6 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

5.1 Sulfate reducing archaea and bacteria are known to contribute to microbiologically influenced corrosion.5.2 Sulfate-reducing bacteria are widely distributed in marine and fresh water muds which, in consequence, frequently are laden with the hydrogen sulfide produced by these organisms during dissimilatory sulfate reduction.5.3 Traditional, culture-dependent methods such as those described in Test Methods D4412, prescribe incubation periods of as long as 21 days before assigning a below detection limit (BDL) score to a specimen. Moreover, it is well known that not all SRP will proliferate in the nutrient media specified in Test Methods D4412.5.4 This test method uses ELISA technology to provide semi-quantitative, culture-independent, SRP bioburden test results in less than 30 min.5.4.1 Because all the reagents and supplies used are non-hazardous and prepackaged for single test use, this test method does not require any apparatus other than a laboratory timer. Consequently, it can be performed at or near the point of sample collection.5.4.2 The opportunity to minimize the delay between sample collection, testing, and results availability translates into timely use of the data to drive preventive and corrective SRB control measures.1.1 This test method provides a protocol for using enzyme-linked immunosorbent assay (ELISA) technology to test water samples for the enzyme adenosine 5’-phosphosulfate reductase (APSr) concentration.1.1.1 APSr is present in all known sulfate reducing protists (SRP – sulfate reducing bacteria – SRB – and sulfate reducing archaea – SRA).1.1.2 As reported in U.S. Patent 4,999,286, APS reductase concentration can be used as a surrogate parameter for estimating SRA bioburdens (Appendix X1 compares results from Test Methods D8243, D4412, and quantitative polymerase chain reaction – qPCR – testing).1.2 This test method has been validated in tap water, oilfield produced water (salinities ranging from 100 g L-1 to 600 g L-1), and fuel-associated water (commonly referred to as bottoms-water).1.3 This test method detects APS reductase semi-quantitatively in the range of 0.001M to 0.1M – correlating to 102 SRP/mL to 106 SRP/mL.1.3.1 As described in Appendix X2 test method sensitivity can be increased 10-fold to 100-fold. However, the precision statistics provided in X apply only to 10-mL specimens.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 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. Some specific hazards statements are given in Section 9 on Hazards.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 Specifications for aggregates require obtaining representative portions of the supply material for testing. Other factors being equal, larger samples will tend to be more representative of the total supply. This practice provides procedures for reducing the large sample obtained in the field, or produced in the laboratory, to a convenient size for conducting a number of descriptive and quality tests. Failure to carefully follow the procedures in this practice could result in providing a non-representative sample to be used in subsequent testing. The individual test methods provide for minimum amount of material to be tested.4.2 Under certain circumstances, reduction in size of the large sample prior to testing is not recommended. Substantial differences between the selected test samples sometimes cannot be avoided, for example, in the case of an aggregate having relatively few large size particles in the sample. The laws of chance dictate that these few particles may be unequally distributed among the reduced size test samples. Similarly, if the test sample is being examined for certain contaminants occurring in only small percentages, caution should be used in interpreting results from the reduced size test sample. Chance inclusion or exclusion of only one or two particles in the selected test sample may importantly influence interpretation of the characteristics of the original sample. In these cases, the entire original sample should be tested.1.1 This practice covers three methods for the reduction of large samples of aggregate to the appropriate size for testing. These techniques are intended to minimize variations in measured characteristics between the test samples selected and the large sample.1.2 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.NOTE 1: Sieve size is identified by its standard designation in Specification E11. The alternative designation given in parentheses is for information only and does not represent a different standard sieve size.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

5.1 This guide provides recommendations for identifying the potential for deleterious AAR and selecting appropriate preventive measures, based on a prescriptive-based or performance approach, to minimize the risk of deleterious reaction. In regions where occurrences of AAR are rare or the aggregate sources in use have a satisfactory field performance record verified by following the guidance in this standard, it is reasonable to continue to rely on the previous field history without subjecting the aggregates to laboratory tests for AAR. In regions where AAR problems have occurred or the reactivity of aggregates is known to vary from source to source, it may be necessary to follow a testing program to determine potential reactivity and evaluate preventive measures. In this guide, the level of prevention required is a function of the reactivity of the aggregate, the nature of the exposure conditions (especially availability of moisture), the criticality of the structure, and the availability of alkali in the concrete.5.2 Risk Evaluation—To use this guide effectively, it is necessary to define the level of risk that is acceptable, as this will determine the type and complexity of testing (Note 1). The risk of deleterious expansion occurring as a result of a failure to detect deleteriously reactive aggregates can be reduced by routine testing using petrography, or laboratory expansion tests, or both.NOTE 1: The level of risk of alkali-silica reaction will depend upon the nature of the project (criticality of the structure and anticipated exposure). The determination of the level of risk is the responsibility of the individual in charge of the design, commonly a representative of the owner, and for structures designed in accordance with ACI 318, the level of acceptable risk would be determined by the licensed design professional.5.3 For conventional structures, preventive measures determined by either performance testing or the prescriptive approach described in this guide can be expected to generally reduce the risk of expansion as a result of ASR to an acceptable level. For certain critical structures, such as those exposed to continuous moisture (for example, hydraulic dams or power plants), in which ASR-related expansion cannot be tolerated, more conservative mitigation measures may be warranted.5.4 There are no proven measures for effectively preventing damaging expansion with alkali carbonate reactive rocks in concrete and such materials need to be avoided.5.5 If an aggregate is identified as potentially deleteriously reactive as a result of ASR, and the structure size, class, and exposure condition requires preventive measures, the aggregate may be accepted for use together with appropriate preventive measures following the prescriptive or performance methods outlined in this guide.1.1 This guide provides guidance on how to address the potential for deleterious alkali aggregate reaction (AAR) in concrete construction. This guide addresses the process of identifying both potentially alkali-silica reactive (ASR) and alkali-carbonate reactive (ACR) aggregates through standardized testing procedures and the selection of mitigation options to minimize the risk of expansion when ASR aggregates are used in concrete construction. Mitigation methods for ASR aggregates are selected using either prescriptive or performance-based alternatives. Preventive measures for ACR aggregates are limited to avoidance of use. Because the potential for deleterious reactions depends not only on the concrete mixture but also the in-service exposure, guidance is provided on the type of structures and exposure environments where AAR may be of concern.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.1.3 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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This specification covers the design, construction, testing, and operating requirements for self-contained pressure-reducing valves for air or nitrogen systems. Pressure-reducing valves shall be either: type I - inlet outlet end connections of the same pressure rating or type II - outlet end connection pressure rating lower than the inlet end connection rating. Valves shall incorporate the design features specified. Pressure-reducing valves shall meet the performance requirements prescribed. Hydrostatic shell test, seal tightness test, and external leakage test shall be performed to meet the requirements prescribed.1.1 This specification covers the design, construction, testing, and operating requirements for self-contained pressure-reducing valves for air or nitrogen systems.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.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 The oxygen content of a powder affects both its green and sintered properties.5.2 Hydrogen loss is a term widely used in the powder metallurgy industry even though the measurement represents an approximate oxygen content of the powder.5.3 Oxygen is the most common hydrogen-reducible constituent of metal powders, and this procedure may be used as a measure of oxygen, reducible under the test conditions, if other interfering elements are absent.1.1 This test method covers the determination of the mass of hydrogen-reducible constituents in the following metal powders: cobalt, copper, iron, and tungsten.1.2 This test method is useful for cobalt, copper, and iron powders in the range from 0.05 to 3.0 % oxygen, and for tungsten powder in the range from 0.01 to 0.50 % oxygen.1.3 This test method does not measure the oxygen contained in oxides such as silicon oxide (SiO2), aluminum oxide (Al2O3), magnesium oxide (MgO), calcium oxide (CaO), titanium dioxide (TiO2), etc. that are not reduced by hydrogen at the test temperatures.1.4 For total oxygen content, vacuum or inert gas fusion methods are available (see Test Methods E1019).1.5 Untis—The values stated in SI units are to be regarded as 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： 515元 / 折扣价： 438 元 加购物车

5.1 The purpose of this guide is to assess the ability of consumer products to reduce malodor intensity from a control state. Several experimental hypotheses are possible, depending on the objective of the test. Possible objectives with respective hypotheses are given in Appendix X1.5.2 Many consumer products are sold commercially with the intent of providing a means of improving the odor quality of a volume of air, or the odor quality of a substrate such as fabric or household surfaces, relative to some existing environmental condition. In the case of air care products, this typically involves the application of an odorous substance into the air space by means of some active or passive mechanism (for example, by spraying, or by evaporation). This procedure is also applicable to other mechanisms of odor reduction (for example, air filtration, chemical reactions, etc.).5.3 Selection of representative malodor sources is of critical importance. The malodor source must be readily available and of a consistent odor quality. A reasonable malodor source should be chemically and aesthetically correct. The experimenter and client must agree upon the appropriateness of a malodor source before further details of the test design are worked out. Experimental variation will be reduced by using uniform malodor sources. Information collected on malodor reduction will thus be more comparable from experiment to experiment and from laboratory to laboratory.5.4 The procedure recommended can be used for assessment of the malodor reduction and elimination efficacy of consumer products including: air fresheners, air filtration products, aerosol/spray and continuous/solid air freshener products, candles, fabric care products including detergents and fabric enhancing/conditioning products, surface care products including carpet care products, surface cleaning products such as sprays etc., pet care products, and other products intended to deliver a malodor reduction benefit. It should be noted that while product evaluations are fundamentally the same, different treatment or measurement techniques may be necessary because of inherent differences in the product delivery systems.5.5 Temporal Aspects—The procedures herein can be applied to evaluate temporal aspects of product performance, such as determining how long it takes for a product to work, or how long it takes malodor to develop (for example, after treatment, etc.).5.6 These procedures can be used to assess efficacy against any standard malodor, regardless of the mechanism of odor removal.5.7 This guide is designed to provide guidance in product formulation and new product development, and for quality control issues.1.1 This guide covers standard procedures for the quantitative sensory assessment of perceived olfactory intensity of malodors for the purpose of assessing the malodor reduction efficacy of consumer products including, but not limited to, air care, fabric care, home care, pet care, and similar products.1.2 This guide is not intended to cover axillary deodorancy; refer instead to Guide E1207.1.3 Malodors may be from natural or synthetic sources.1.4 This guide is a compendium of information or series of options that does not recommend a specific course of action. The user of this guide is responsible for identifying the most appropriate test design and using the appropriate statistical tools to address the experimental design.1.5 This guide is designed to provide guidance in product formulation and new product development, and for quality control issues.1.6 The scope of this guide does not include all guidance necessary to support claims. For further guidance the researcher may refer to Guide E1958. The usage of methods described in this guide can be used as part of a comprehensive claims support strategy for technical types of claims (such as claims that the product will create a sensory change when used on malodor). However, this guide does not address other important elements of the claim support strategy, including determining the statistical confidence requirements, or determination of the consumer relevance of the data obtained, as discussed in 1.7.1.7 The testing of products designed to reduce malodors via sensory testing as outlined in the present Guide can yield technical support for products’ efficacy claims. The methods described in this guide—assesors with identified sensory acuity and trained, malodors that may be lab-created or synthetic, and controlled exposure to malodors in a controlled indoor environment—can deliver results with high internal validity. Internal validity refers to studies designed so that variables that may obscure the finding of an effect are controlled or managed. It is important to recognize that internal validity does not assure external validity. A robust support strategy for a malodor efficacy claim is stronger with additional evidence that the sensory effect is consumer perceivable. Such evidence of product’s malodor reduction efficacy may be, for example, drawn from studies where consumers serve as evaluators, or where the product is used to reduce malodors in a more representative environment (for example, at home).1.8 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 6 and X3.6.3.7.1.9 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.

定价： 646元 / 折扣价： 550 元 加购物车

This specification covers self-contained, internally operated, globe style, pressure-reducing valves for use in steam service. In these valves, the downstream pressure feedback is sensed by a spring-loaded diaphragm to position a pilot valve—the pilot valve uses the inlet steam pressure to position the main valve plug via an operating piston. The valves shall be of the following compositions: Composition B made with 1.25% chromium, 0.5% molybdenum and Composition B made with carbon steel. All materials shall be selected to prevent corrosion, galling, seizing, and excessive wear or erosion where applicable. Clearances shall prevent interference as a result of the thermal expansion. Cadmium plating is prohibited. Components of these valves shall include body, bonnet, bottom cover, internal trim, cylinder liner, piston, gaskets, diaphragm, springs, and bolts. Valves will be operated, maintained, and repaired on board ships and shall emphasize simplicity, maintainability, ruggedness, and reliability. Design shall permit access for adjustment and repair when working from either side of the valve and without requiring removal of the valve body from the line. Each production valve shall be subjected to the following tests: nondestructive test, hydrostatic test, seat tightness test, and external leakage test.1.1 This specification covers self-contained, internally operated, globe style, pressure-reducing valves for use in steam service. In these valves, the downstream pressure feedback is sensed by a spring-loaded diaphragm to position a pilot valve—the pilot valve uses the inlet steam pressure to position the main valve plug by means of an operating piston.1.2 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.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 The impact sound rating for a floor assembly is determined both by the basic floor assembly and the floor covering on the upper surface. The same floor covering in combination with different basic floor assemblies will not always give the same impact insulation class (IIC) ratings. This test method is designed to provide data that characterize the floor covering alone when installed over concrete slab floors.5.2 The ΔIIC rating calculated in 13.4 is used to compare the effectiveness of different floor coverings on concrete floors.5.3 The impact insulation class (IIC) calculated for the reference concrete floor with a covering provides an indication of the impact sound insulation that the covering will provide with typical, monolithic concrete floors.5.4 When the normalized impact sound pressure levels below a bare concrete slab are known, the difference spectrum calculated in 13.1 may be used to estimate the impact sound pressure levels and hence the IIC that would result if the covering were installed on the slab.5.5 Warning: Difference spectra measured using this method shall not be used to estimate impact sound pressure levels for floors comprising only one or two lightweight floor layers such as oriented strand board or plywood. Such estimated impact sound pressure levels would be very inaccurate.NOTE 1: The difference spectrum calculated in 13.1 gives unreliable estimates of the reduction in impact sound pressure levels due to the floor covering when it is placed on a joist floor incorporating a concrete topping (about 50 mm thick) poured directly on the plywood subfloor or steel deck. The estimated impact sound pressure levels are too low.35.6 This test method closely follows that described in ISO 10140-1 (Annex H) except that the single number rating used is the impact insulation class (IIC) described in Classification E989. The description of the standard concrete floor also differs.NOTE 2: The requirement in Classification E989 that no deviation above the reference contour may exceed 8 dB means that there is no simple relationship between ISO 10140-1 (Annex H) test ratings and those generated by this method.1.1 This test method describes a method for the laboratory measurement of the effectiveness of floor coverings in reducing impact noise from a standard tapping machine through concrete floors. The test results are not necessarily directly related to the subjective evaluations of the floor coverings.1.2 This test method applies to all floor coverings, whether single or multi-layered, as installed on a standard concrete floor. Multi-layered coverings may be factory-assembled or assembled at the test laboratory.1.3 The test method applies only to laboratory measurements. It does not apply to the measurement of the effectiveness of a floor covering in a field situation.1.4 Laboratory Accreditation—A procedure for accrediting a laboratory for performing this test method is given in Method E492.1.5 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.

定价： 590元 / 折扣价： 502 元 加购物车