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The screw customization non-standard screw industry will conduct testing on the products produced

The non-standard screw industry conducts testing on products produced, such as irregular screws, non-standard screws, and so on. After testing, we will identify areas where the product is not qualified, in order to better improve our own product. Only in this way can we provide customers with higher quality products and win the favor of users.

Non-standard screw

Testing, appearance, and quality requirements for non-standard screws in fasteners; Visual inspection of non-standard screws and inspection of electroplating layer. The thickness inspection of screw coating can be carried out using micrometers, vernier calipers, plug gauges, etc. The magnetic method for measuring the thickness of a coating layer is a non-destructive measurement of a non magnetic coating layer on a magnetic substrate using a magnetic thickness gauge; Microscopic method, also known as metallographic method, involves magnifying corroded fasteners on a metallographic microscope with a micrometer eyepiece to measure the thickness of the coating on the cross-section; Timing liquid flow method.

The timed liquid flow method uses a solution that can dissolve the coating to flow onto a local surface of the coating, and calculates the thickness of the coating based on the time required for the local coating to dissolve. There are also coating droplet method, anodic dissolution Coulomb method, and so on. Inspection of adhesion strength of screw coating: There are many methods to evaluate the adhesion between coating and substrate metal, usually including the following: friction polishing test; File method test; Scratch method; Bending test; Thermal shock test; Squeeze method. Corrosion resistance inspection of stainless steel screw coating: the corrosion resistance inspection methods of the coating include: atmospheric exposure test; Neutral salt spray test (NSS test); Acetate spray test (ASS test), copper accelerated acetate spray test (CASS test); And corrosion paste corrosion test (CORR test) and solution droplet corrosion test; Immersion test, inter immersion corrosion test, etc.