This specification covers a group of common requirements that shall apply to carbon, alloy, and stainless steel fasteners or fastener materials, or both. These materials are intended for use at any temperature from cryogenic to the creep range. Requirements for the melting process and quality control procedures for ingot cast and strand cast products are detailed. Bars and fasteners shall be produced in accordance with the product specification. The chemical composition, as to heat and product analyses, shall conform to the limits of the product specification. Bars, fasteners, bolting materials, and specimen machined from fasteners shall meet the mechanical requirements which shall be determined by the following tests: (1) proof load test by mandrel/tension or compression methods, (2) cone proof load test, (3) impact test, and (4) hardness test. Assembly for the proof load and cone proof tests are illustrated. The depth of decarburization shall be determined by metallographic etching and if needed, microhardness testing.1.1 This specification covers a group of common requirements that shall apply to carbon, alloy, stainless steel, and nickel alloy bolting under any of the following ASTM Specifications (or under any other ASTM Specifications that invoke this specification or portions thereof):Title of Specifications ASTM DesignationAlloy-Steel and Stainless Steel Bolting for High Temperature or High Pressure Service and Other Special Purpose Applications A193/A193MCarbon Steel, Alloy Steel, and Stainless Steel Nuts for Bolts for High Pressure or High Temperature Service, or Both A194/A194MAlloy-Steel and Stainless Steel Bolting for Low- Temperature Service A320/A320MStainless and Alloy-Steel Turbine-Type Bolting Specially Heat Treated for High-Temperature Service A437/A437MHigh-Temperature Bolting, with Expansion Coefficients Comparable to Austenitic Stainless Steels A453/A453MAlloy-Steel Bolting for Special Applications A540/A540MPrecipitation-Hardening Bolting (UNS N07718) for High Temperature Service A1014/A1014MHigh Strength Precipitation Hardening and Duplex Stainless Steel Bolting for Special Purpose Applications A1082/A1082M1.2 In case of conflict, the requirements of the individual product specification shall prevail over those of this specification.1.3 Fasteners are a wide-ranging classification that includes screws, bolts, nuts, washers, stud bolts, rivets, powder-actuated studs, staples, tacks, and pins. Bolting, which is composed of bolting materials, such as rods, bars, flats, and forgings, which are subsequently manufactured into bolting components, are a special sub-group of fasteners. Bolting materials and components have designated compositions and specific properties intended for applications in aggressive service where commercial generic fasteners may not be suitable or have insufficient fitness for purpose under certain conditions. These conditions include cryogenic or high temperature service, or excessive vibration, impact, or shock. To further address any other special service conditions where bolting is intended for use, additional requirements may be specified by mutual agreement between the purchaser and supplier.1.4 Supplementary requirements are provided for use at the option of the purchaser. The supplementary requirements only apply when specified individually by the purchaser in the purchase order or contract.1.5 This specification is expressed in both inch-pound units and in SI units. Unless the purchase order or contract specifies the applicable “M” specification designation (SI units) the inch-pound units shall apply. The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.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 principal underlying the test is the sensitivity of the electrical contact interface to temperature and humidity cycling that electrical pressure connection systems experience as a result of usage and installation environment. The temperature cycling may cause micromotion at the mating electrical contact surfaces which can expose fresh metal to the local ambient atmosphere. The humidity exposure is known to facilitate corrosion on freshly exposed metal surfaces. Thus, for those connection systems that do not maintain stable metal-to-metal contact surfaces under the condition of thermal cycling and humidity exposure, repeated sequences of these exposures lead to degradation of the contacting surface indicated by potential drop increase.5.2 The test is of short duration relative to the expected life of connections in residential usage. Stability of connection resistance implies resistance to deterioration due to environmental conditions encountered in residential service. Increasing connection resistance as a result of the test exposure indicates deterioration of electrical contact interfaces. Assurance of long term reliability and safety of connection types that deteriorate requires further evaluation for specific specified environments and applications.5.3 Use—It is recommended that this test method be used in one of two ways. First, it may be used to evaluate and report the performance of a particular connection system. For such use, it is appropriate to report the results in a summary (or tabular) format such as shown in Section 17, together with the statement “The results shown in the summary (or table) were obtained for (insert description of connection) when tested in accordance with Test Method B812. Second, it may be used as the basis for specification of acceptability of product. For this use, the minimum test time and the maximum allowable increase in potential drop must be established by the specifier. Specification of connection systems in accordance with this use of the standard test method would be of the form: “The maximum potential drop increase for any connection, when tested in accordance with Test Method B812 for a period of weeks, shall be mV relative to the reference connections.” Connection systems that are most resistant to thermal-cycle/humidity deterioration, within the limitations of determination by this test method, show no increase in potential drop, relative to the reference connections, when tested for indefinite time. Connections that are less resistant to thermal-cycle/humidity conditions applied by this test will demonstrate progressive increases in potential drop with increasing time on test. Thus, the following examples of specifications are in the order of most stringent (No. 1) to least stringent (No. 3). Duration, weeks Maximum Potential Drop Increase, mV1. 52 02. 16 0.23. 4 1.01.1 This test method covers all residential pressure connection systems. Detailed examples of application to specific types of connection systems, set-screw neutral bus connectors and twist-on wire-splicing connectors, are provided in Appendix X1 and Appendix X2.1.2 The purpose of this test method is to evaluate the performance of residential electrical pressure connection systems under conditions of cyclic temperature change (within rating) and high humidity.1.3 The limitations of the test method are as follows:1.3.1 This test method shall not be considered to confirm a specific lifetime in application environments.1.3.2 The applicability of this test method is limited to pressure connection systems rated at or below 600 V d-c or a-c RMS.1.3.3 This test method is limited to temperature and water vapor exposure in addition to electrical current as required to measure connection resistance.1.3.4 This test method does not evaluate degradation which may occur in residential applications due to exposure of the electrical connection system to additional environmental constituents such as (but not limited to) the following examples:1.3.4.1 Household chemicals (liquid or gaseous) such as ammonia, bleach, or other cleaning agents.1.3.4.2 Chemicals as may occur due to normal hobby or professional activities such as photography, painting, sculpture, or similar activities.1.3.4.3 Environments encountered during construction or remodeling such as direct exposure to rain, uncured wet concrete, welding or soldering fluxes and other agents.1.3.5 This test method is limited to evaluation of pressure connection systems.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 become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.1.5 This standard should be used to measure and describe the properties of materials, products, or assemblies in response to electrical current flow under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual installation conditions or under actual fire conditions. However, results of this test may be used as elements of a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end 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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