发明名称 |
METHOD AND APPARATUS FOR EVALUATING CLAMP FORCE IN A BOLT BY MEANS OF ULTRA-SONIC MEASUREMENTS |
摘要 |
In an apparatus and a method of evaluating a clamp force (F) in a threaded joint between a bolt and a matching threaded piece during a tightening operation, a torque (T) provided to the joint is continuously measured and ultra-sonic pulses are simultaneously induced into the bolt such that a time of flight (TOF) of the pulses in the bolt is measured. In response to an increase of the measured torque (T) an increase rate (dT/dα) of the torque (T) is determined, from which an initial rotation angle (α0) where the torque (T) starts to increase due to bolt deformation is determined. An increase rate (dTOF/dα) of the time of flight (TOF) is also determined. A total increase of the time of flight (ΔTOF) during the tightening operation is then determined based on the initial rotation angle (α0) and the increase rate (dTOF/dα) of the time of flight (TOF). |
申请公布号 |
EP2936098(A1) |
申请公布日期 |
2015.10.28 |
申请号 |
EP20130802376 |
申请日期 |
2013.12.10 |
申请人 |
ATLAS COPCO INDUSTRIAL TECHNIQUE AB |
发明人 |
PERSSON, ERIK VILHELM;ROLOFF, ARNE TORGNY |
分类号 |
G01L5/24;G01L5/00 |
主分类号 |
G01L5/24 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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