BRIEF INTRODUCTION TO STRAIN GAUGE TEMPERATURE SELF-RETRIEVE THEORY

Install the strain gauge onto the test sample which is free of outside force and restriction. Its indication strain changes when the temperature changes,which is called heat output.Heat output is the resulf of linear expansion coefficient difference synergy between resistance temperature coefficient,sensitive bar material and the test sample material.

The ordinary strain gauges’s hot output is often very high, hot output is the biggest erroneous source during static strain testing, and hot heat dispersion increases when heat output increasra, this discreoancy is even bigger gradient or transient appears in the testing environment. Thus the ideal strain gauge shall be called temperature self-retrieve strain gauge.

To achieve this, internal crystal strucutre reformed through adjustment of the alloy ingredient allocating proportion of the strain gauge sensitive bar and proper heat treatment, to change hte resistance temperature coefficient to make the heat output value as close as zero, thus realizing its self-retrieve function for elastomer or test sample, meeting the production requirment of high accuracy stress analysis and the sensor.

STRAIN GAUGE CREEP SELF-RETRIEVE THEORY AND MENTHODS

The sensor elastic element has the inherent micro-creep characteristic because of its material’s an elasticity effect, which is manifested by the increases of sensor’s output along with the time increases (positive and negative creep). The resistance strain gauge’s basus and pastes have certain viscoelasticity, which makes strain gauge’s output to increase when time reduces. We may carry on retrievement for the elastic element’s anelasticity by improving strain guage sensitive bar’s structure peoportion and the related craft to adjust its direction and the value.

When selecting strain gauge after elastomer is confirmed, we can choose strain gauge between one or neighbouring creep tabs for testing based on the creep tab information peoviede by the manufacturer, to choose the strain gauge which really matchs the shensors. In addition, the creep of the sensor is related to elastomer, strain gauge and adhesvie, furthermore, its influenced by clamp stress, temperature, time control, seal structural style, protection rubber,producion technique, etc, which should be taken into consideration when choosing strain guage cerrp tab.