Service HotlineIt can be seen from the extrusion process that the screw works under high temperature, certain corrosion, strong wear and high torque. Therefore, the screw must: 1) High temperature resistance, no deformation under high temperature; 2) Wear resistance, long life; 3 ) Corrosion resistance, the material is corrosive; 4) High strength, can withstand large torque, high speed; 5) Good cutting performance; 6) After heat treatment, the residual stress is small, and the thermal deformation is small. [1]
The main purpose of the screw is to make the industrial product form a fixed one. In use, it often happens that the teeth cannot be closely attached, the screw head will be broken if the screw is locked too hard, or the tooth pattern is not properly locked, etc., and the use conditions are not met, all of which are quality. the problem of accuracy. Screws are mass products, not handmade works of art. In mass production, the purpose is to achieve high-precision and stable quality and popular prices to supply consumers. The accuracy of screws is usually 6g, and the rough screws used in construction projects are 10g. The value of screws is very important. In the world, there are examples of automobile factories going bankrupt because of poor screw quality; there are also examples of planes falling and vehicles being overturned because of poor screw quality.
High-strength bolt connection has the advantages of simple construction, good mechanical performance, disassembly and replacement, fatigue resistance, and no loosening under dynamic load. It is a promising connection method. High-strength bolts use a special wrench to tighten the nut, so that the bolt generates a huge and controlled pre-tension. Under the action of pre-pressure, a large frictional force will be generated along the surface of the connected parts. Obviously, as long as the axial force is less than this frictional force, the components will not slip and the connection will not be damaged. This is the high-strength bolt connection. principle. High-strength bolted connections rely on the friction between the contact surfaces of the connectors to prevent them from sliding each other. In order to make the contact surfaces have sufficient friction, it is necessary to increase the clamping force of the components and increase the friction coefficient of the contact surfaces of the components. The clamping force between the components is achieved by applying pretension to the bolts, so the bolts must be made of high-strength steel, which is why it is called high-strength bolted connections. In high-strength bolted connections, the friction coefficient has a great influence on the bearing capacity. Tests show that the coefficient of friction is mainly affected by the form of the contact surface and the material of the components. In order to increase the friction coefficient of the contact surface, methods such as sandblasting and wire brush cleaning are often used to treat the contact surface of the components within the connection range during construction.
Fasteners are a type of mechanical parts that are used for fastening connections and are widely used. All kinds of fasteners can be seen on all kinds of machinery, equipment, vehicles, ships, railways, bridges, buildings, structures, tools, instruments, meters and supplies. It is characterized by a wide variety of specifications, different performance uses, and a very high degree of standardization, serialization and generalization. Therefore, some people also refer to a type of fasteners with existing national standards as standard fasteners, or simply as standard parts. Fasteners are the most widely used mechanical foundations. With my country's entry into the WTO in 2001, it has entered the ranks of major international trade countries. my country's fastener products are exported to many countries in the world, and fastener products from all over the world are also pouring into the Chinese market. Fasteners, as one of the products with the largest import and export volume in my country, are in line with international standards, which have important practical significance and practical significance for promoting Chinese fastener enterprises to go to the world and promoting fastener enterprises to fully participate in international cooperation and competition. strategic significance. Due to the specifications, dimensions, tolerances, weights, properties, surface conditions, marking methods, and specific requirements of items such as acceptance inspection, marking and packaging for each specific fastener product.
1. Correctly select the product a. Before use, confirm whether the mechanical properties of the product can meet the needs of use, such as the tensile strength of the screw and the guaranteed load of the nut. The length of the screw should be selected appropriately, and the 1-2 pitch of the nut will be exposed after tightening. b. Before use, check whether the threads are rough, and whether there is iron filings or dirt between the threads, which often lead to locking. c. The fasteners can be lubricated before use. It is recommended to use butter, molybdenum disulfide, mica, graphite or talc for lubrication. Generally, dipping wax is used for lubrication and anti-locking. [1] 2. Pay attention to the use method when using it. a. The speed and force of screwing in should be appropriate, not too fast or too large. Use a torque wrench or socket wrench as much as possible, and avoid using an adjustable wrench or an electric wrench. Excessive speed will cause the temperature to rise rapidly and cause lock-up. b. In the direction of force, the nut must be screwed in perpendicular to the axis of the screw. c. The use of washers can effectively prevent the problem of over-tightening.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: ultra-thin nuts, insulating plastic screws, hollow hexagon bolts, set extension bolts and other products, we can provide you with suitable fastener solutions for you Program.
