Reasons for errors in hydraulic universal testing machine

Hydraulic universal testing machine is widely used in various materials such as hardware, metal, rubber and plastic, footwear, leather, clothing, textiles, insulators, wires and cables, terminals, etc. During the testing process, it can automatically obtain conventional data such as elastic modulus, yield strength, tensile strength, fracture strength, sample elongation, and cross-sectional shrinkage rate. However, errors cannot be avoided. The following are common errors in the test results of hydraulic universal testing machines summarized by our technical personnel based on their experience:

1. Hydraulic system error: an error that persists in a certain numerical or regular variation. Systematic errors have a pattern, which is manifested in every detailed experiment. Once this pattern is found, it can be corrected.

Root cause analysis:

1) The indication of the hydraulic universal testing machine is inaccurate, and the measured force value is always too large or too small.

2) The error of the coefficient on the instrument panel when measuring strain with a resistance strain gauge.

2. Error: Errors caused by errors in experimental work, neglect of carelessness, and other reasons. This kind of error has no regularity and can be prevented by repeated verification.

Root cause analysis:

The hydraulic universal testing machine was operated incorrectly, and the experimenter misread the numbers and wrote the decimal point position incorrectly when recording.

3. Random error: that is, under the same conditions, repeatedly stopping and measuring the same parameter, the measured values obtained cannot be completely the same.

Root cause analysis:

1) Changes in frictional force inside the testing machine during the experimental process

2) Changes in environmental humidity, etc.