Impact testing machine refers to the material testing machine that applies impact test force to the sample to conduct impact test. Impact testing machines are divided into manual pendulum impact testing machines, semi-automatic impact testing machines, digital impact testing machines, microcomputer-controlled impact testing machines, drop hammer impact testing machines and non-metallic impact testing machines. By replacing the pendulum and sample base, the test of simple beam and cantilever beam can be realized.
If the impact testing machine has been used for a long time, some common faults will occur. About the common faults encountered:
1. When conducting tensile test, the fracture of the sample is always broken on both sides.
2. The sensitivity of the dial pointer is poor, the position of the pendulum is abnormal, and the pendulum rod of the impact testing machine is not aligned vertically.
3. The hammer return is abnormal, fast and slow. The passive needle cannot stop at any position and does not coincide with the main needle.
4. When loading, the oil circuit system has serious oil leakage or the oil pipe is broken.
5. After the sample breaks, the pendulum falls back quickly, causing impact.
Generally, the solutions to the failure of impact testing machine are as follows:
1. The jaw is not placed correctly when clamping, and the sample shall be clamped symmetrically according to the requirements.
2. The jaw quality is poor and the teeth are damaged, which not only affects the different centers of the jaw, but also makes the sample slip during the test, making the yield point difficult to identify. At this time, replace the jaw.
3. The lifting guide wheel is not adjusted correctly, so that the upper and lower jaws are not concentric. One inspection rod shall be machined. After the upper and lower jaws are tightened, measure with a dial indicator based on two force columns until the adjustment is qualified. Replace the oil with proper viscosity. Check whether the joint of the oil circuit system is tightened, and replace the gasket if necessary. If the oil pipe is broken, check whether the joint of the oil circuit system is tightened. If the gasket needs to be replaced, replace it in time. If the oil pipe is broken, it is necessary to replace the oil pipe with higher strength. In addition, observe whether the oil delivery valve and overflow valve piston are stuck or installed reversely. Common fault: after the sample breaks, the pendulum falls back quickly, causing impact.
