Service HotlineIn all kinds of machines and equipment, the various parts are fixed and assembled by bolts and nuts. However, after the machine and equipment are used for a period of time, the bolts and nuts will become loose, which will bring great safety hazards to the use of the machine and equipment. For this reason, when bolts and nuts are used for connection, a spring washer is installed between the nut and the connected part. The spring washer is in the shape of a circular ring, and the ring is not closed, and is sleeved on the bolt. The addition of the spring washer has a certain anti-loosening effect, but it can only prevent the nut from rotating relative to the bolt. In the case of large vibration of the machine, the bolt will rotate relative to the connected part.
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.
screw can be equipped with only one spring washer or only one flat washer, or it can also only be equipped with a two-piece combination of flower teeth. The national standard number of the combination screw is represented by GB9074. The commonly used cross recessed small pan head three combination screw national standard is GB9074.8.
To sum up, the chip nut provided by Guangdong Yueluo Hardware Industry Co., Ltd. has a circle of serrated teeth 1011 protruding outwardly on the edge of the welding end face 101. During welding, the excess solder overflows and flows to the periphery. In the gap between the serrated teeth 1011, on the one hand, the solder on the welding end face 101 can be made uniform, so as to ensure that the welded chip nut is neat and beautiful; The welding area is increased, and the firmness and reliability of the welding are improved.
Bolt material: 18Cr2Ni4W, 25Cr2MoV steel; bolt specification: M27～M48. Because this kind of steel is easy to form a passivation film on the surface, and this passivation film will make the bolt unable to obtain a good adhesion chemical nickel phosphorus layer, so special pretreatment measures must be taken to remove the film first, and measures should be taken To prevent its regeneration, it is possible to ensure a good bonding force between the plated coating and the substrate. At the same time, due to the large geometric size of the bolt, it increases the difficulty of nickel-phosphorus plating treatment and quality inspection of the process.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: hand-knocked punch rivets, set nuts, wave elastic washers, motherboard copper posts and other products, we can provide you with suitable fastening products piece solution.
