【国外标准】 Standard Test Method for Longitudinal Tensile Properties of “Fiberglass” (Glass-Fiber-Reinforced Thermosetting-Resin) Pipe and Tube

4.1 Tensile properties include modulus of elasticity, yield stress, elongation beyond yield point, tensile strength, elongation at break, and energy absorption. Materials possessing a low order of ductility may not exhibit a yield point. Stress-strain data at several levels of temperature, humidity, time, or other variables may be needed to furnish reasonably accurate indications of the behavior of the material.4.2 Tension tests may provide data for research and development, engineering design, quality control, acceptance or rejection under specifications, and for special purposes (Note 3). The tests cannot be considered significant for applications differing widely from the load-time scale of the standard test (Note 4). Such applications require more suitable tests, such as impact, creep, and fatigue.NOTE 3: It is realized that the method of preparation of a material is one of the many variables that affect the results obtained in testing a material. Hence, when comparative tests of materials per se are desired, the greatest care must be exercised to ensure that all samples are prepared in exactly the same way; similarly, for referee or comparative tests of any given series of specimens, care must be taken to secure the maximum degree of uniformity in details of preparation, treatment, and handling.NOTE 4: Reinforcements of plastics with glass fiber offer wide opportunities for designing and producing products with markedly different responses to loading even when the basic geometry of the product is similar. For example, a tubular product may be designed to give maximum resistance to torsion loading, but such a product might develop a twist or bow if tested in tension or under internal pressure loading. In the case of pipe for general field use, internal pressure, as well as loads in tension, compression, torsion, and flexure must be resisted to some degree. Different pipe producers have chosen, by design, to offer products having different balances of resistance to such stressing conditions. As a result, it is important that the purchaser and the seller both have a clear understanding and agreement on the significance of this test method relative to the intended use.1.1 This test method covers the determination of the comparative longitudinal tensile properties of fiberglass pipe when tested under defined conditions of pretreatment, temperature, and testing machine speed. 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 polymer.1.2 This test method is generally limited to pipe diameter of 6 in. (150 mm) or smaller. Larger sizes may be tested if required apparatus is available.1.3 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are provided for information purposes only.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.NOTE 2: There is no known ISO equivalent to this 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.