Stud Manufacturer teaches everyone how to inspect screws. "Screw surface inspection can be divided into two types, one is the inspection before the screw is manufactured without plating, and the other is the inspection after the screw is plated, in other words, after the screw is hardened, The inspection after the surface of the screw is resolved. After the screw is manufactured and before being plated, everyone will carry out the inspection of the specifications, dimensional tolerances and other levels of the screw. See if there is any way to meet the national industry standards or customer regulations. After the screw surface is resolved, everyone The electroplated screws are inspected, and the key is to inspect the color of the electroplating and the wood or broken screws. Then when everyone sends the screws to the customers, the customers can successfully pass the customs when they pick them up. Inspection after the screws are resolved:
1. Appearance quality regulations
The appearance inspection of Full Threaded Stud is to carry out inspections at all levels such as appearance and plating.
2. Inspection of the thickness of the screw coating
1. Measuring instrument method
The amount used includes vernier calipers, micrometers, plug gauges, etc.
2. Magnetic method
The precise measurement of the thickness of the coating with the magnetic method is a non-destructive and accurate measurement of the conventional non-magnetic coating with a magnetic coating thickness gauge.
3. Optical microscope method
The optical microscope method is called the metallographic analysis method, which is to place the corroded standard part on a stereo microscope equipped with a micrometer eyepiece to enlarge it, and accurately measure the thickness of the coating on the cross section.
4. Hourly flow method
The time-keeping flow method is to use an aqueous solution that can melt the plating layer to flow on part of the surface of the plating layer, and measure the thickness of the plating layer according to the time necessary for the partial plating layer to end. There are also coating spot method, anodic oxidation melting coulometric method and so on.