How to check the quality of screws? The screw factory summarized the following: Check the appearance of the screw: First, check whether the electroplating layer of the screw is qualified, and secondly, check whether the appearance of the screw has serious defects. If there is a corresponding wrench, you should stop the machine or car in time, tighten it, and then use it again.

In fact, the best solution is to find out in advance, as long as these problems are found in advance, then there will be no accidents in the use process. At the same time, we must deal with the loose screws accordingly. For some anti-theft screws, the best way is to bring them to the manufacturer to make them again.

Testing the corrosion resistance of screws: The corrosion resistance of the coating is tested by: atmospheric exposure test; neutral salt spray test (NSS test); acetic acid salt spray test (ASS test), copper accelerated acetic acid salt spray test ( CASS test); and corrosive paste corrosion test (CORR test) and solution spot corrosion test; immersion test, inter-immersion corrosion test and so on.

Second, check whether the thickness of the screw is qualified: If you want to check the thickness of the screw, then you need to use the measuring tool method, the magnetic method, the microscope method, and the timing flow method to meet this detection method. This kind of screw is special, and other wrenches cannot be tightened. Test China Wafer Head Cement Board Screw Company strength: If you want to test the strength of the screw, you must learn the friction polishing test; the file method test; the scratch method; the bending test; the thermal shock test.

Therefore, in order to ensure everyone's safety, we must always check whether the screws are in good condition.Once the screws are loose, it will cause a lot of adverse effects. Then, how to solve the loose screws? For machines that cannot be stopped at present, the best way is to reduce the speed of mechanical movement and observe the dynamics of the screws at any time