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见到ABS规范上要求,一、二级管路上的阀的材质为铸钢或是球墨铸铁,如果是球墨铸铁,则要求其性能在50mm内有12%的延展性要求。
一直没搞懂,延展性12%为什么还要有50mm的要求?(Nodular iron may be used for Classes I and II piping systems and for valves listed in 4-6-2/3.1.3,provided it has an elongation of not less than 12% in 50 mm (2 in.).
请高手帮忙解释下,这个到底啥意思? |
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