There are many kinds of hardness meters. Metal Rockwell, Brinell and Vickers hardness meters are widely used in industrial and mining enterprises and scientific research institutions. Among them, metal Rockwell and metal Brinell hardness meters have simple structure compared with metal Vickers hardness meters. The adjustment and repair of common faults is not very difficult.
Common faults and solutions of Vickers hardness tester:
(1) The loading indicator light and measuring microscope light are not on
First check whether the power supply is connected properly, and then check the switch, bulb, etc. If it is not on after eliminating these factors, we should see whether the load is fully added or whether the switch is normal. If it is still abnormal after elimination, it must be checked step by step from the line (circuit).
(2) Measure the turbidity in the microscope, and you can't see or see the indentation clearly
This should start with adjusting the focal length and light of the microscope. If it is still unclear after adjustment, rotate the objective lens and eyepiece respectively, and move the three flat lenses with dotted line, solid line and scribed line in the lens respectively, carefully observe which mirror is the problem, then remove it, scrub it with long fiber absorbent cotton stained with anhydrous alcohol, and observe it after it is installed in the reverse order. If it is still not solved, Send for repair or replace the micrometer microscope.
(3) The indentation is not in the field of view or the workbench is slightly rotated, and the indentation position changes greatly
The reason for this is that the axes of indenter, measuring microscope and worktable are different. Since the indenter is fixed at the bottom of the working shaft, adjust it respectively in the following order:
① Adjust the movable clearance at the lower end of the main shaft so that the lower end face of the guide seat does not directly contact the conical surface of the main shaft;
② Adjust the screw on the side of the rotating shaft so that the working shaft and the main shaft are in the same center. After adjustment, press out an indentation on the test block, observe its position in the microscope and record it;
③ Gently rotate the workbench (ensure that the test block does not move on the workbench) and find a point on the test block that does not rotate under the microscope, which is the axis of the workbench;
④ Slightly loosen the screw on the pressing plate of the lifting screw rod and the bottom screw, gently move the whole lifting screw rod to make the axis of the worktable coincide with the position of the indentation recorded in the measuring microscope, then tighten the pressing plate screw and adjusting screw, and press out an indentation to compare with each other. Repeat the above steps until they are completely coincident.
(4) Causes and solutions of indication out of tolerance during verification:
① The measuring microscope scale is inaccurate. Check with a standard micrometer. If not, it can be sent for repair or replacement.
② Diamond indenter defect. Observe with an 80x stereo microscope to see whether it meets the provisions of the verification regulation of diamond indenter. If there is any defect, replace the indenter.
③ If the load (load) exceeds the specification requirements or the load is unstable, check it with a small load third-class standard dynamometer. If the load exceeds the requirements (± 1.0%) but the direction is the same, the lever proportion changes. Loosen the main shaft protective 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 blunt blade of force point, wear of fulcrum steel ball, non concentricity between working shaft and main shaft, large friction in working shaft, etc. At this time, check the blade and steel ball. If it becomes blunt or worn, it shall be repaired or replaced. Check and clean the working shaft. Be sure to match the steel balls around the shaft. See Step 3 for the adjustment of the same (shaft) center.
(5) Impact during loading:
The occurrence of this situation is related to too little or dirty oil in the buffer. It can generally be solved after filling the oil or cleaning the buffer.
To sum up, this is the common problems and solutions of Vickers hardness tester learned by staff. I hope it will help you. If you need to know other relevant knowledge, you can contact our customer service personnel through the web page. We will answer them one by one. We look forward to your call and support!
Contact Person: Ms. Victoria Li
Tel: +86 13929216856