Introduction to scratch tester:

   The strength, hardness and adhesion of the film are important physical properties of the film, and their size directly affects the important properties of the film, such as wear resistance, abrasion resistance, scratch resistance, impact resistance, retention and cleanliness of the film, etc. Therefore, the strength and hardness of the film are the necessary indicators to evaluate the performance of the film. Physical properties such as film strength, hardness and adhesion can be easily evaluated by scratch tester. Therefore, the purpose of scratch tester is to characterize the film strength, hardness and adhesion by the penetration resistance of the film template coating during needle engraving.

Working principle of scratch tester:          

Scratch tester is mainly composed of a needle rack and a work table, the needle rack to ensure vertical action on the film template (the template is fixed on the test bench on the workbench, can be moved horizontally or longitudinally; Lateral movement can be motorized or manual after turning off the power, and longitudinal movement is manual). 

    After switching on the power switch, the red indicator light on the power switch indicates that the instrument is powered on. In this case, the return switch is in the "experiment" state. The table moves from right to left, the needle contacts with the sample in the "experiment" trip, and the return trip (the return switch is pulled to the "return" state). The table moves from left to right, the needle is lifted and does not touch the sample, and the weight added on the needle holder is changed to measure whether the film can be scratched under different weights. The minimum weight required to scratch the film is used to determine the scratch resistance value of the film.

Use of scratch tester:

1.Preparation: Prepare 120mm×50mm (0.2~0.3mm thick) as required or prepare paint film according to the bottom plate specified by the product.

2.Check the scratch tester:turn on the scratch tester and use the power supply (220V). press the main switch (power switch) of the scratch tester and then toggle the twister switch to the "experiment" stroke, and the test rig will move laterally (to the left) to stop, and then pull the twister switch to the "return" stroke, and the test rig will move laterally (to the right) to stop. Note: the middle position of the twister switch can be "stopped" urgently.

3.According to the monitoring on the scratch tester, twist (move) the pointer of the meter to move, and at the same time scratch the indicator light is normal.

4.A new needle should be installed in the scratch tester. The needle should first be checked by an accessory 30 times magnifying glass. There should be no scratches, non-round, rust spots and other defects. The height of the needle should be appropriate.　

5.Clamp the template into the template clamp of the test bench of the scratch tester, with the coating facing up, and turn the longitudinal handle to move the test bench to the remote end (the test bench and table are flush) as the initial position.

6.Put the minimum weight (50g) or a slightly smaller load weight to plan to break the film on the weight table of the scratch tester.

Scratch Tester Test:

    Switch THE WORKING button to the "EXPERIMENT" position, DELIMit the needle on the template, with the eye to observe whether to scratch, such as scratch, the meter pointer move, and scratch the indicator light. If not scratched, pull the working switch to "return", so that the test bench returns to stop at the right end, and then slightly move the handle longitudinally (forward rotary) to move the test bench a bit (the second scratch will not overlap on the first scratch), at the same time, it is necessary to replace the scratch needle with a new inspection method as before, And put a heavier weight on the counterweight table and that's all you need to make the second scratch.

  Repeat the above test until the coating is scratched (at this time, the scratch light is on and the pointer of the meter moves, and a 10x magnifying glass can also be used to observe whether the scratch is scratched and the bottom plate is exposed, and the scratch length of the scratched part should be greater than 20mm). At this time, the weight of the weight is the scratch resistance value of the coating (the measured value of this method).

    The minimum load is determined to be the scratch resistance value of the film after the test load is repeated to the original sample and the same new sample

   When the measured load value is different, then take the average of three times of the load value for the anti-scratch value of the film.

Maintenance of scratch tester:

   Scratch tester use strive to rotate flexible, should pay attention to lubrication should be between rotating parts and rotating parts and relative moving parts between the injection of oil.

   Scratch tester in use after a period of time, to fully check the fasteners to prevent looseness.

    When the scratch tester is not in use, pay attention to dust-proof, moisture-proof, corrosion-proof, avoid vibration and collision.

Note: Due to the continuous upgrade of the product, the picture is for reference only, please write to consult the details!

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