Service HotlineInspection method There are two types of screw surface inspection, one is the inspection before the screw is produced and not plated, and the other is the inspection after the screw is plated, that is to say, after the screw is hardened and the surface of the screw is treated. . After the screws are produced and before electroplating, we inspect the screws in various aspects such as size and tolerance. See if there are national standards or customer requirements. After the surface treatment of the screws, we will inspect the plated screws, mainly to check the color of the plating and whether there are any broken screws. In this way, when we deliver screw goods to customers, customers can successfully pass the customs when they receive the goods. Inspection of screws after treatment: 1. Appearance quality requirements The inspection of the appearance of screws is carried out from the aspects of appearance, electroplating layer and so on. Second, the inspection of the thickness of the screw coating 1. The measuring tool method uses a micrometer, a vernier caliper, a plug gauge, etc. 2. Magnetic method The magnetic method is used to measure the thickness of the coating layer, which is a non-destructive measurement of the non-magnetic coating layer on the magnetic substrate with a magnetic thickness gauge. 3. Microscopy Microscopy is called metallographic method, which is to magnify the etched fasteners on a metallographic microscope with a micrometer eyepiece to measure the thickness of the coating on the section. 4. Timing flow method The timing flow method uses a solution that can dissolve the coating to flow on the local surface of the coating, and calculates the thickness of the coating according to the time required for the local coating to dissolve. There are also coating drop method, anodic dissolution Coulomb method, etc. 3. Inspection of the adhesion strength of the screw coating There are many methods for evaluating the adhesion between the coating and the base metal, usually the following. 1. Friction polishing test; 2. File method test; 3. Scratch method; 4. Bending test; 5. Thermal shock test; 6. Extrusion method. 4. Inspection of corrosion resistance of screw coatings The corrosion resistance inspection methods of coatings include: atmospheric exposure test; neutral salt spray test (NSS test); acetate salt spray test (ASS test), copper accelerated acetate salt spray test (CASS) test); and corrosion paste corrosion test (CORR test) and solution spot corrosion test; immersion test, inter-dipping corrosion test, etc.
The existing spring pads are generally composed of longitudinal support springs, transverse connection springs, support springs, frames and frame clips. (Commonly known as string spring) is a slender and constant warp spring, used to connect the longitudinal support spring. The support spring is located at the edge of the spring pad to increase the shear resistance of the spring pad and the support strength of the frame. The surrounding frame connects the spring to the spring. up, fixed. The existing treatment method is to first heat-process the longitudinal support spring and the support spring made of 70# steel wire through the winding spring in a chemical solution, arrange them, and fix and connect them with a string spring, a frame and a clamping piece. Because the string spring and the frame have not been chemically heat treated, there is a large internal stress. Therefore, this treatment method has two disadvantages. One is that the processing efficiency of the heat treatment support spring is low. Larger, the spring is easily deformed and the service life is affected. In addition, the chemical solution after heat treatment is easy to cause environmental pollution
The circuit board is often the circuit board that plays a major role in electrical equipment, and the main electrical components of the circuit are often integrated on the motherboard. For single-layer circuit motherboards, rivets are used on the circuit motherboard in order to make the components more firmly fixed on the pcb board. In the prior art, the rivets are all set on the circuit board by an automatic riveting machine, which is controlled by an internal program to automatically complete the rivet-setting operation. This internal program is pre-set. If you need to rivet different motherboards, you must change the internal program. If you need to temporarily rivet a circuit board, it will be cumbersome to change the program again. Moreover, this kind of automation equipment is produced on a large scale and is not suitable for temporary operations.
The main operation method of the embedded knurled copper nut of the lock nut is injection molding. After heating, it is embedded into the plastic part or directly injection molded. If injection molding is used, the melting point of P/NYLOY/PET is above 200°C. , After the embedded nut is hot melted into the plastic part, the temperature rises rapidly. After injection molding, the plastic body rapidly cools and crystallizes and hardens. If the embedded nut temperature is still at a high temperature, it may fall to the place where the copper nut contacts the plastic part. Start to loosen or crack. Therefore, copper nuts are used instead of carbon steel nuts in the injection molding of embedded nuts.
Commonly used national standard GB41Ⅰ type hexagon nut——C grade GB6170Ⅰ type hexagonal nut——, B grade GB6171Ⅰ type hexagonal nut-fine thread-, B grade GB6172 hexagonal thin nut——, B grade - chamfering GB6173 hexagonal thin nut—— Fine thread—, B grade GB6174 hexagonal thin nut—B grade—without chamfering
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: bolt and nut sets, Torx thumbscrews, thin flat washers, stainless steel DIN912 screws and other products, we can provide you with suitable fastener solutions for you Program.
