A Drilling Positioning Fixture for Residual Stress Measurement by Small Hole Method

Abstract

The invention discloses a drilling and positioning fixture for measuring residual stress by a puncture method, and belongs to the technical field of stress test. The drilling and positioning fixture comprises a base, an adjustable support frame and a drilling fixture. The adjustable support frame is disposed on the base, and the drilling fixture of an elongated double-hollow-square-block bar is connected to the adjustable support frame. Strain gauges distributed on one line or one area can be drilled by rotating the base, adjusting the adjustable supporting frame and rotating the drilling fixture without moving the fixture repeatedly and considering whether a drilling position is horizontal or vertical or not. The drilling and positioning fixture is especially applicable to the situations that a drilling surface is a curve surface, a groove tube surface and an upturned surface. By the arrangement, working steps of repeatedly adjusting screw threads, demounting the fixture, applying glue, waiting for the glue to be dry, and the like are reduced as compared with the existing drilling and positioning fixture for measuring the residual stress method, and therefore, efficiency and accuracy in measuring the residual stress with the puncture method are greatly improved.

Description

technical field [0001] The invention relates to the technical field of drilling stress testing by the small hole method, in particular to a drilling positioning fixture for measuring residual stress by the small hole method on complex spatial positions of complex workpieces. Background technique [0002] When the small hole method is used to measure the residual stress, it is necessary to use a special fixture for positioning to ensure that the small hole drilled is exactly the center of the strain gauge pasted at the measurement point. At present, the small hole method mainly uses three-legged or four-legged fixtures for stress measurement; screw threads and nuts are used for horizontal and vertical adjustment, and glue is used to fix the positioning fixtures on the test piece. It mainly has the following disadvantages: it can be used for the measurement of the horizontal plane, but the ordinary fixture cannot meet the requirements when measuring the curved surface, tubular...

AI Technical Summary

Problems solved by technology

It mainly has the following disadvantages: it can be used for the measurement of the horizontal plane, but the ordinary fixture cannot meet the requirements when measuring the curved surface, tubular surface, groove, upward surface and some other non-horizontal positions; and the measurement of residual stress in engineering applications It is mainly in the place with complex stress, that is, the place with complex structure, so it cannot be used in engineering, and can only be used in the laboratory; every time a point is tested, the fixture needs to be removed, installed and fixed, the work efficiency is very low, and a lot of time is wasted

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