In the tensile test, first of all, we should consider the phenomenon of total two-sided fracture. The main body of the testing machine should be installed vertically to eliminate seeds and then eliminate them on three sides.

1. Whether the jaws are clamped shall be tested as required.

2. In addition to affecting the quality of the gripper of the tester, if the test process slips and the yield point is difficult to determine, the gripper should be replaced.

3. Adjust the lifting guide wheel, so that the jaws are tightened with the aid of the inspection rod, and measure with a multimeter until the adjustment is qualified.

I put forward a solution and hope to adopt it.