The pressure test of hardware spring generally uses electronic digital display spring tension and compression testing machine. The electronic digital display spring tension and compression testing machine is a special instrument for testing the relationship between the deformation and the load of the tension and compression springs. It is suitable for testing the working load of tension and compression springs under a certain working length, and can also be used for the elastic load testing of elastic devices such as rubber and reeds.
The pressure test of hardware spring is generally divided into the following steps:
1 Before the formal inspection and measurement, first compress the spring to the test load once. When the test load is greater than the pressure and load, the compression load is used as the test load, but the maximum compression force does not exceed 1.5 times the constant pressure and load. .
2 “Preparation for load inspection and measurement: use a third-class dynamometer corresponding to the corresponding range or a weight with a precision of more than one to calibrate the load test machine to ensure that the accuracy of the test machine is not less than 1%; correct the load with the use block The length reading error of the testing machine.
3 Inspection and determination of the load of the hardware spring pressed to the specified height: place the gauge block with the same height as the specified height in the center of the pressure plate of the load tester; load the load on the gauge block near the nominal value of the pattern; lock the positioning screw or positioning pin; Take out the gauge block, put in the spring to be tested, adjust the zero position, remove the weight of the spring; press the spring to the specified height, and read the corresponding load; according to the calibration error of the load test machine, the reading is corrected.
4) Press the upper pressure plate to the position where it is just in contact with the spring, the load testing machine predicts F0≈0.05F; record the initial reading of the load test F0 and the reading of the length indication; continue to load to change the value of the reading predicted by the length Has reached the designated amount of variants.