Service HotlineGenerally, we have to divide the fine thread nut and the coarse thread nut first, but in fact, no matter what kind of fine thread, coarse thread, their specifications are the same, their specifications are M3, M4, M5, M6, M8, M10, etc. . But there is another kind of hexagonal nut, which is divided into English and American, which is only a different national standard. Made in China, it is called the national standard hexagon nut
In order to meet the needs of different assembled installation components, there are also hand-tightening methods for tightening the screws, but in actual use, ordinary manual screws can easily cause hand pain to the user, and the operation is extremely inconvenient; at the same time, due to tightening The contact area between the screw and the installation component is too small. If the user exerts too much force, the uneven force per unit area of the installation component will cause deformation and depression, which will affect the use. Therefore, a manual screw is proposed to solve the above problems.
The isolating switch in the substation has a large workload for maintenance. The transmission parts such as the isolating switch connecting rod are mostly connected by cylindrical pins. The shaft-pin fit is generally 1mm, which is tight. If the cylindrical pin is disassembled during the maintenance process, it is often due to corrosion and mechanical deformation. It is difficult to proceed smoothly for other reasons, and if the working environment is a small space, it is more difficult to disassemble. In traditional operations, grinding, hard prying, or beating with a hand hammer are often used to disassemble, which will further deform the pins, and when the space is small, it is difficult to use tools such as hand hammers. solve.
Hexagon nuts are usually used in conjunction with bolts and screws to connect and fasten parts. In daily life, ordinary hexagon nuts are sometimes welded to metal plates for use. In the process of welding hexagon nuts to metal plates In order to ensure that the center line of the inner thread of the hexagonal nut is perpendicular to the metal plate, it is necessary to press the end face of the hexagonal nut on the metal plate before welding. Part of the melt is melted. Since the weld is close to the inner thread of the hexagonal nut, the inner thread is often deformed, which affects the fit of the hexagonal nut and the bolt.
In the manufacture of fasteners, the correct selection of fastener materials is an important part, because the performance of fasteners is closely related to its materials. If the material is improperly or incorrectly selected, the performance may not meet the requirements, the service life may be shortened, or even accidents or processing difficulties may occur, and the manufacturing cost will be high. Therefore, the selection of fastener materials is a very important link. Cold heading steel is a steel for fasteners with high interchangeability produced by cold heading forming process. Because it is formed by metal plastic processing at room temperature, each part has a large amount of deformation and a high deformation speed. Therefore, the performance requirements of cold heading steel raw materials are very strict. On the basis of long-term production practice and user research, combined with GB/T6478-2001 Technical Conditions for Cold Heading and Cold Extrusion Steel GB/T699-1999 High-Quality Carbon Structural Steel and target JISG3507-1991 Cold Heading Characteristics of Carbon Steel Wire Rod for Steel, taking the material requirements of grade 8.8 and grade 9.8 bolts and screws as an example, the determination of various chemical elements. If the C content is too high, the cold formability will be reduced; if it is too low, the mechanical properties of the parts cannot be met, so it is set at 0.25% - 0.55%. Mn can improve the permeability of steel, but adding too much will strengthen the matrix structure and affect the cold forming performance; when the part is quenched and tempered, it has the tendency to promote the growth of austenite grains, so it should be appropriately improved on the basis of international standards. 0.45 % - 0.80 %. Si can strengthen the ferrite and reduce the cold formability. SP is an impurity element, and their existence will cause segregation along the grain boundary, resulting in the embrittlement of the grain boundary and damage to the mechanical properties of the steel. It should be reduced as much as possible. B. The maximum value of boron content is 0.005%, because although boron element can significantly improve the permeability of steel, it will also increase the brittleness of steel. Excessive boron content is very unfavorable for workpieces such as bolts, screws and studs that require good comprehensive mechanical properties.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: tooth rod bolts, hexagonal head reinforcing rod bolts, tooth hexagonal fine-tooth nuts, B-type single-pass copper insert nuts and other products, we can provide you with Provide the right fastener solution for you.
