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ASME B40.100-1998 Gauge.pdf
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其中P25页的第6章Pressure Gauge Testing 有我们关心的内容
6.2.4.1(b) All Grade.Known pressure shall be applied at each test point on increasing(or vacuum). At each test point the gauge shall be read,lightly tapped, and then read again. The difference reading is friction error.
对于所有等级的压力表。在升压行程逐步施加已知压力在每个测试点。读取每个测试点上压力表读数,然后轻敲,再读取一次。两次读数差值即为压力表的摩擦误差。
friction error 好像就是咱们国家的“轻敲位移”吧。
The same sequence shall be repeated on decreasing (or vacuum). The entire set of upscale and downscale reading shall then be repeated.
THe error can be determined from the data abtained in the two pressure cycles and is equal to maximum error at each test point, in either direction, after tapping.
然后6.2.4.2 Repeatability 重复性 ,6.2.4.3 Hysteresis 迟滞性(类似咱们国家的回程误差)。
可以肯定地说known pressure 并不一定等于测试点压力,国外的活塞按1、2、2、5规则配备了小MPa砝码,可以通过加小砝码使被检压力表指针对齐标有数字分度线。 |