Flange bolt tension and working load online monitoring method

Abstract

The invention provides a flange bolt tension and working load online monitoring method. The method comprises the following steps: installing a high-precision displacement sensor at a flange connectionpart, collecting and correcting flange relative displacement data, calculating bolt tension and external load at a bolt connection part according to the displacement data, further calculating to obtain total working load acting on a flange, comparing the calculated values with preset thresholds respectively, and performing early warning when the values exceed the thresholds. The flange axial relative displacement can be monitored through the high-precision displacement sensor, online monitoring of the bolt tension and the flange working load is conducted, full-automatic processing can be achieved, the calculation efficiency is high, the flange bolt tension and flange working load change situation is monitored online in real time, and equipment damage caused by failure of flange connectingbolts or overlarge flange working load is avoided; and tension and flange working load of all flange bolts can be accurately and comprehensively monitored by reasonably arranging the number and positions of the high-precision sensors.

Description

technical field [0001] The invention relates to an online monitoring method for flange bolt tension and working load, and belongs to the technical field of flange bolt tension and load monitoring. Background technique [0002] Flange connection refers to the connection of flanges, gaskets and bolts as a detachable structure. Flange connection is extremely common in the current industrial field and plays a very important role. The flange connection structure will be subjected to various alternating loads and impact loads during work. Under the action of alternating tension and compression loads, the thread may be plastically deformed to cause the bolt to loosen, and the tension of the bolt will decrease. If the bolt tension is too small, the connection will be unreliable, which will affect the normal operation of the machine. If the bolt tension is too large, it may cause the bolt to break under the load, thereby weakening the bearing capacity of the connecting node, and in...

AI Technical Summary

Problems solved by technology

[0005] 1) Using ultrasonic technology to monitor bolt tension online, this technology needs to install ultrasonic probes and other monitoring sensors or equipment on each planned monitoring bolt, which has high cost, long preparation time and on-site construction time; for flange bolts, it needs to be disassembled, reinstalled The installation of bolts will cause the friction coefficient to change during the bolt tightening process, which will affect the accuracy of monitoring data; the number of monitoring equipment is large, and the installation is easy to loosen, so the probability of failure is high; the number of bolts that can be monitored is limited, and comprehensive and all-round monitoring cannot be realized

[0006] 2) Use the strain gauge technology to measure the bolt tension. When this technology is applied to field measurement, the first thing to solve is the signal transmission of the strain gauge. Since the gap between the screw and the screw hole is very small, it is very difficult to realize the signal transmission of the strain gauge. At the same time, the connection surface of the flange bolts will slip slightly under the load during the working process, which may cause damage to the resistance strain gauge. Therefore, the reliability of the resistance strain gauge measurement bolt tension is not high, and it is not suitable for field use Engineering Applications

[0007] 3) Use pressure sensor technology to measure bolt tension. Although this method has high measurement accuracy, it destroys the integrity and integrity of the workpiece, and sometimes it cannot be installed due to the limitation of geometric space.

[0008] To sum up, although the existing technology has made a certain contribution to the online monitoring of bolt tension, there are still many deficiencies and cannot meet the needs of many practical engineering applications.

[0009] Regarding the online monitoring technology of flange working load, there are very few technologies available in the market

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