美标和中国检定规程的试验机同轴度测试方法对比

Comparison on Alignment Test Methods of Testing Machine between ASTM and Chinese Calibration Guideline

采用美国标准(ASTM)ASTM E1012-2014和中国检定规程JJG 475-2008,JJG 556-2011对试验机同轴度进行测试,并对测试方法和测试结果进行了对比。结果表明:ASTM和中国检定规程在定级标准、装置(试样棒)、操作方法及计量溯源等方面都有所不同。ASTM采用应变片试样棒,中国检定规程采用双引伸计法。ASTM对于同轴度的检验方法更加全面完整,但缺乏完善的计量溯源方式。中国检定规程易于操作,同时能保障计量溯源,但不能同时保证试棒在全方位反映出试验机的同轴度。

The alignment of testing machine was tested by using ASTM E1012-2014 and China calibration guideline JJG 475-2008 and JJG 556-2011, and the test methods and test results were compared. The results show that the ASTM and China calibration guideline were different in grading standard, device(specimen rod), operation method and metrological traceability. The strain gauge specimen rod was used in ASTM, and the double extensometer method was used in Chinese calibration guideline. The alignment test method in ASTM was more comprehensive and complete, but it lacked perfect metrological traceability. China calibration guideline was easy to operate, and can guarantee the metrological traceability, but it can not guarantee that the test rod reflects the alignment of the testing machine in all directions.