Things to note when using hardness meter, common troubleshooting methods and scientific maintenance methods

A hardness meter is an instrument that measures the hardness of an object. It measures the hardness of rubber or plastic of a scraper blade. According to the traditional and simple degree, it can be divided into two types: simple hardness meter and complex hardness meter. The principle is expressed by the plastic deformation concentration of the pressed material under the action of the load (including preload and main load). According to the measured hardness units, there are: Rockwell hardness meter, Vickers hardness meter, micro hardness meter, Brinell hardness meter, Shore hardness meter, Pap hardness meter, Richter hardness meter, Webster's hardness meter, etc. Below we will introduce some precautions, common troubleshooting methods and scientific maintenance methods when using hardness meter.

The following precautions when using the hardness meter:

1. The hardness meter itself will produce two kinds of errors: one is the error caused by deformation and movement of its parts; the other is the error caused by the hardness parameters exceeding the specified standards.

Each hardness scale has a de facto scope of application and must be correctly selected according to regulations. Because when it exceeds its specified test range, the accuracy and sensitivity of the hardness meter are poor, the hardness value is inaccurate, and it is not suitable for use. Other hardness testing methods also stipulate corresponding calibration standards. The standard block used for calibration hardness meter cannot be used on both sides, because the hardness of the standard and back sides may not be consistent. Generally, the standard block is valid within one year from the date of calibration.

2. When replacing the indenter or anvil, be careful to wipe the contact area clean. After replacement, test with a steel sample of certain hardness several times until the hardness value obtained twice in succession is the same. The purpose is to tighten the indenter or anvil with the contact part of the tester and make good contact so as not to affect the accuracy of the test results.

3. After the hardness meter is adjusted, the first test point is not used when the hardness is measured. Because I was afraid that the sample and the anvil would not come into contact with it well, the measured value was inaccurate. After the special test is completed, the test sample is formally tested after the hardness meter is in normal operation mechanism state and the measured hardness value is recorded.

4. When the specimen allows, generally select different parts to test at least three hardness values, take the average value, and take the average value as the hardness value of the specimen.

5. For specimens with complex shapes, pads of corresponding shapes must be used, and they can be tested after being fixed. The round specimens should generally be placed in a V-shaped groove for testing.

6. Before loading, check whether the loading handle is placed in the unloading position. The movement should be light and steady when loading, and do not use too much force. After loading, the loading handle should be placed in the unloading position to avoid the instrument being in a load state for a long time, plastic deformation will occur, affecting the measurement accuracy.

Troubleshooting methods for hardness meter:

Method for eliminating low display value of hardness meter

1. The steel ball and punch in the steel ball clutch are dirty, or the diameter of the steel ball is inconsistent. When the punch jumps back to the highest position, the steel ball clutch cannot lock the punch immediately, causing the measured punch jump height to be low and the mitochondria value to be reduced. In this way, the steel ball and punch should be cleaned, or the steel ball should be replaced so that the steel ball clutch should work normally.

2. The damper is dirty, the piston rises and is stuck, and the sleeve 27 cannot return to the highest position, which makes the hardness meter display low. The damper should be cleaned.

3. The elastic force of the disc spring is too small, and the sleeve 27 cannot return to the highest position, which makes the hardness value too low. The positioning stop pin nail should be removed, turn the knob 25 clockwise for several turns to increase the elasticity of the disc spring, and then tighten the positioning stop pin screw.

4. The protective cap is too high, so that the punch can fall freely at a low height. The protective cap should be adjusted appropriately to ensure that the punch drop height meets the requirements.

5. If the diamond punch is damaged or the spherical radius at the top is too small, the punch should be polished or replaced.

Method for eliminating the high display value of the hardness meter

1. The protective cap is too low to make the punch drop height higher. The position of the protective cap should be adjusted appropriately.

2_The spherical radius at the top of the diamond punch is too large, so the punch should be polished or replaced.

When the hardness meter is working, several consecutive sounds of punch impacting the sample.

The main reason for this failure is that the opening spring 39 is too elastic or the gap between the sleeve 27 and the steel ball seat 26 is dirty, and the steel ball clutch does not act as a locking function, causing the punch to continuously impact the sample. In this way, the elastic force of the opening spring should be adjusted appropriately, and the opening spring should be replaced if necessary; if the sleeve and steel ball seat are dirty, it should be cleaned.

When the hardness meter sleeve 27 is resuming, the pointer of the hardness indicator rotates too fast

1. Dirt enters between the baffle of the damper and the damping piston, causing the two to be incompatible and the damping device to lose its damping effect. The damper should be cleaned

2. The piston and cylinder are seriously worn, so the piston should be replaced.

Scientific maintenance methods for hardness meter:

1. Use hardness meter, be careful and take care of it.

The moving hardness meter should be held gently, and the packaging and shockproof should be paid attention to. Because most hardness meters use LCD liquid crystal panels, if strong collision, squeezing and vibration occur, the position of the liquid crystal panel may move, which will affect the convergence of images during projection, and the phenomenon that RGB colors cannot overlap. At the same time, the hardness meter has a very precise optical system. If vibration occurs, it may also cause the lens and mirror in the optical system to be displaced or damaged, affecting the projection effect of the image. The zoom lens may also cause the lens to get stuck or even break under impact.

2. When the hardness meter is not used for a long time, use a dust cover to cover the machine and regularly inject a small amount of sewing machine oil into the contact surface between the lead screw and the handwheel.

3. Before using the hardness meter, wipe the top surface of the screw and the upper end surface of the workbench. If you find that the hardness meter display error is large, you can take the workbench down and check whether the contact surface with the screw is clean. Check whether the screw protective sleeve is lifted up the workbench, and check whether the pressure head is damaged.

4. When replacing the indenter or anvil, be careful to wipe the contact area clean. After replacement, test with a steel sample of certain hardness several times until the hardness value obtained twice in succession is the same. The purpose is to tighten the indenter or anvil with the contact part of the tester and make good contact so as not to affect the accuracy of the test results.

5. After the hardness meter is adjusted, the first test point is not used when the hardness measurement begins. Because I was afraid that the sample and the anvil would not come into contact with it well, the measured value was inaccurate. After the special test is completed, the test sample is formally tested after the hardness meter is in normal operation mechanism state and the measured hardness value is recorded.

6. The loading and unloading pressure head should be carefully and carefully to ensure that the tip is free of damage and pollution, and the installation surface is clean and free of foreign objects. If not used for a long time, you should remove it and store it properly and pay attention to prevent rust.

7. The surface of the sample table and standard hardness block should be clean and pollution-free, without scratches, rubbing, or bruising; apply anti-rust oil to prevent rust when stored.

8. During the test, the sample under test must be placed smoothly and has reliable support to ensure that there is no displacement or deformation during the test.

9. Pay attention to dust-proof and corrosion-proof media in daily working environment and after shutdown. In some humid areas, rust prevention should be paid frequently.

This is the precautions, common troubleshooting methods and scientific maintenance methods when using hardness meter that I have introduced to you to your friends. Hope it helps everyone!