With the advancement of technology in various industries, the current structural design of screws has evolved from just simple locking to focusing on work efficiency during the locking process and not destroying the integrity of the objects to be locked. The new cases such as No. 556784 screw improvement and No. 289405 screw that integrates locking, stability, labor-saving, fast and multi-function which were previously designed and approved and published in the Central Taiwan Bulletin are the main representatives of screws. It is clear that It is learned that the two cases not only fully improve the shortcomings of the traditional simple locking screws, but also achieve the purpose of substantial improvement of the screws designed in each case in actual use.
High-strength fastener materials mainly include ML35, 35K, ML40Cr, ML35CrMo steel, etc., of which 75ML35CrMo steel is imported. The main problems of the material are box segregation, decarburization, cracks and so on. The material needs to be spheroidized and annealed before cold forming, and the annealing is carried out in an oil furnace. There is no protective atmosphere in the furnace, and there is a decarburization phenomenon. 1.2 The high-strength fasteners, mainly grade 12.9, are quenched and tempered on the chain casting furnace production line. The temperature and atmosphere in the furnace are controlled by computer, and Rx gas is used as a protective atmosphere. Heating and anti-oxidation and decarburization can be effectively controlled, and the quality of the fasteners is intact during the heating process. The high-strength fasteners mainly of grade 8.8 are quenched and tempered on the vibrating hearth furnace. Affected by the structure of the vibrating hearth furnace, the sealing performance of the furnace is poor, the Rx atmosphere is not easy to control, the temperature difference of the furnace is large, and the parts are heated in the furnace. The collision and the length of time are inconsistent, and the quality of the fasteners during the heating process is poor, and there are phenomena such as decarburization, bumps, and uneven heating.
1. Precautions for the quality of high-strength bolts or screws and flat washers assemblies. The surface of the Phillips hexagon combination screw should be checked for burrs or scratches. There is no oil stains, or rust. To test the material of the combination screw, the strength of the grade used in different high strengths should be consistent with it. Second, the combination bolt and nut should be used together with the same grade as the nut, and the same grade should be used together. Third, when installing and using combined bolts, it should be in reasonable weather conditions and should not be operated in the rain. Fourth, when installing, it is forbidden to use excessive force and excessive force. Lead to sliding teeth, or locking phenomenon.
Heat resistance refers to both the oxidation resistance or gas medium corrosion resistance at high temperature, that is, thermal stability, and at the same time, it has sufficient strength at high temperature, that is, thermal strength. As the material requirements of products produced by customers are getting higher and higher, the requirements for screws used in product materials are also getting higher and higher. When product materials face harsh environments and special occasions, more and more high-quality mechanical properties of stainless steel screws are used. Therefore, stainless steel screws were selected. The requirements are getting higher and higher, and the material of stainless steel screws is getting higher and higher. Therefore, many ordinary stainless steel screws SUS201 are replaced by stainless steel SUS304 screws and stainless steel screws SUS316. Of course, if some requirements are not so high, general customers will choose stainless steel screws SUS201, which are relatively cheap in cost.
In the design of electrical products, in order to avoid the problem of electromagnetic radiation interference, it is necessary to isolate the conduction between metal parts (parts). Especially when the metal parts are locked by metal screws, the conduction between the locked pair of metal parts (parts) is often caused, so it is necessary to try to isolate them. For example, when screws are used to lock the structure iron of the liquid crystal display screen and the iron structure of the foot base, the electromagnetic waves generated by the liquid crystal display screen are easily radiated from the foot base, causing electromagnetic radiation interference.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: trimmed hexagonal alloy steel screws, carbon steel grade 4.8 screws, high-strength material 10.9 special accessories, Torx screws and other products, we can provide you with suitable products Your fastener solution.