How to troubleshoot common faults in Vickers hardness testers?

According to the Vickers hardness tester report, check the hardness tester switch, light bulb, etc. If these factors are ruled out and still do not light up, or if the loading indicator light or measuring microscope light does not light up, the repair method is to first check whether the power supply is properly connected. Just check if all the loads are added or if the reed switch is working properly. If it is still abnormal after elimination, it is necessary to start from the circuit and gradually investigate. The fault of turbidity inside the measuring microscope, inability to see or clear indentation: Maintenance method: This should start with adjusting the microscope focal length and light. If it is still unclear after adjustment, the objective lens and eyepiece should be rotated separately, and the three flat mirrors with dotted, solid, and engraved lines inside the mirror should be moved. Carefully observe which mirror surface the problem is on, then remove it, wipe it clean with long fiber degreased cotton dipped in anhydrous alcohol, and install it in the opposite order before observation. If it still does not solve the problem, send it for repair or replace the micrometer microscope. Faults where the indentation is not within the field of view or when the workbench is slightly rotated, resulting in significant changes in the indentation position: The reason for this situation is due to the different axial centers of the indenter, measuring microscope, and workbench. As the indenter is fixed at the bottom of the working shaft, it is adjusted in the following order. Adjust the clearance at the lower end of the spindle to ensure that the lower end of the guide seat does not directly contact the spindle cone surface; Adjust the screw on the front side of the shaft to align the working shaft with the main shaft. After adjustment, make an indentation on the test block, observe its position in the microscope, and record it; Gently rotate the workbench to ensure that the test block does not move on the workbench. Find a point on the test block that does not rotate under the microscope, which is the axis of the workbench; Slightly loosen the screws and bottom screws on the pressure plate of the Vickers hardness tester's lifting screw, gently move the entire lifting screw, so that the axis of the workbench coincides with the position of the indentation recorded in the measuring microscope, then tighten the pressure plate screws and adjustment screws, and press an indentation to compare with each other. Repeat the above methods until they overlap. The cause and maintenance method of the malfunction of the indication exceeding the tolerance during calibration: the scale of the measuring microscope is not accurate. Use a standard micrometer for inspection. If not allowed, it can be sent for repair or replacement. Diamond indenter defect. Observe with an 80x stereo microscope to see if it complies with the diamond indenter calibration regulations. If there is any defect, replace the pressure head. If the load exceeds the requirements of the regulations or the load is unstable, check with a small load third class standard dynamometer. If the load exceeds the requirement by ± 1.0% but the direction is consistent, this is a change in the lever ratio. You can loosen the spindle maintenance cap, turn the power point contact, adjust the load lever ratio, and tighten it after adjustment. If the load is unstable, it may be caused by factors such as the force point blade becoming blunt, the fulcrum steel ball being worn, or the working shaft not being concentric with the main shaft, or significant friction inside the working shaft. At this time, check the blade and steel ball. If they become dull or worn, they should be repaired or replaced. Check the working shaft and clean it, be sure to match the steel balls around the shaft. Faults with impact phenomenon during loading: Causes and maintenance methods: This situation is related to insufficient or dirty buffer oil. After filling up the oil or cleaning the buffer, it can generally be solved. Vickers hardness tester
The commonly used metal Rockwell, Brinell, and Vickers hardness testers in industrial and mining enterprises, as well as scientific research institutions, are rare faults and maintenance methods for Vickers hardness testers. There are many types of hardness testers. The structure of metal Rockwell and Brinell hardness testers is relatively simple compared to metal Vickers hardness testers. Repairing rare faults is not very difficult. Below is an introduction to the rare troubleshooting of the metal Vickers hardness tester. Based on years of work practice, before starting calibration and repair work, it is necessary to start by adjusting the level of the workbench, and then observe whether the spindle, lever, lifting screw, buffer mechanism, and measuring device are normal and flexible. Ensure a basic understanding of device performance. Then, address each situation one by one.