【国外标准】 Standard Specification for Flexible Transition Couplings for Underground Piping Systems

This specification describes the properties of devices or assemblies suitable for use as flexible transition couplings for underground drainage and sewer piping systems. Couplings that may include bushings or inserts, and meet the requirements of this specification are suitable for joining plain end pipe or fittings. Couplings shall be permitted to have a center stop, the components shall be designed so that the elastomeric material is compressed to form a hydrostatic seal when the joint is assembled. Assemblies shall be tested in different areas and each component shall conform to specified physical and mechanical requirements, namely: hardness, tensile strength, elongation, heat aging, hardness, ozone resistance, water absorption, and chemical resistance for the elastomeric materials; tension band performance, torque resistance, free running torque for the stainless steel materials; and deflection sealing resistance, and shear loading resistance for the joint assemblies.1.1 This specification describes the properties of devices or assemblies suitable for use as flexible transition couplings, hereinafter referred to as “couplings,” for underground drainage and sewer piping systems.1.2 Flexible transition couplings that conform to the requirements of this standard are suitable for joining plain-end pipe or fittings. The pipe to be joined shall be of similar or dissimilar materials, size, or both.1.3 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.1.4 The ASTM standards referenced herein shall be considered mandatory.1.5 The committee with jurisdiction over this standard is not aware of another comparable standard for materials covered in this standard.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.