Service HotlineBolts made of high-strength steel, or bolts that require a large pre-tightening force, can be called high-strength bolts. High-strength bolts are mostly used for the connection of bridges, rails, high-voltage and ultra-high-voltage equipment. The fracture of this kind of bolt is mostly brittle fracture. High-strength bolts applied to ultra-high pressure equipment need to be prestressed to ensure the sealing of the container.
According to the force of the connection, it is divided into ordinary and hinged holes. According to the shape of the head: there are hexagonal head, round head, square head, countersunk head and so on. Among them, the hexagonal head is the most commonly used. Generally, countersunk heads are used where connections are required. The English name of the riding bolt is U-bolt. It is a non-standard part. The shape is U-shaped, so it is also called a U-bolt. There are threads on both ends that can be combined with nuts. It is mainly used to fix tubular objects such as water pipes or sheets such as automobile plates. Springs are called riding bolts because of the way they fix things like a person rides a horse. According to the length of the thread, it is divided into two categories: full thread and non-full thread. According to the thread type, it is divided into two types: coarse thread and fine thread. The coarse thread type is not displayed in the bolt mark. The bolts are divided into eight grades: 3.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, and 12.9 according to their performance grades. Among them, the bolts above grade 8.8 (including grade 8.8) are made of low-carbon alloy steel or medium-carbon steel and are heat-treated (quenched). + Tempering), commonly known as high-strength bolts, and below grade 8.8 (excluding 8.8) are commonly known as ordinary bolts. Ordinary bolts can be divided into three grades: A, B, and C according to the production accuracy. Grades A and B are refined bolts, and grade C is rough bolts. For connecting bolts for steel structures, unless otherwise specified, they are generally ordinary rough grade C bolts. There are differences in the processing methods of different grades. Usually the corresponding processing methods are as follows: ① The bolts of grade A and B bolts are processed by lathes, with smooth surfaces and accurate dimensions. High, rarely used; ②C-grade bolts are made of unmachined round steel, the size is not accurate enough, and its material property grade is 4.6 or 4.8. The deformation is large during shear connection, but the installation is convenient and the production cost is low. It is mostly used for tensile connection or temporary fixation during installation.
pressure riveting nut pressure riveting tool Yueluo relates to a tool, specifically a pressure riveting nut pressure riveting tool. [Background Art] In order to quickly press riveting nuts, and to quickly switch press rivet nuts of different specifications and properties, and to ensure the press riveting strength between the press riveting nut and the piece during the press riveting process, a kind of Press riveting tooling. In order to overcome the deficiencies of the prior art, Yueluo provides a pressure riveting tool that can improve the strength of the pressure riveting and can switch the pressure riveting nut of different specifications and properties.
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.
T-slot convenient bolt that can be used for the middle port of the T-slot and directly realizes the assembly and tightening of the bolt and the nut. Technical Background At present, the bolts for T-slots are assembled from two side ports of the T-slots. When the length of the T-slot is long, it is time-consuming and laborious to install from the side port to the center port at the designated position. In addition, the two side ports of the T-slot are often blocked by other components, and the bolts for the T-slot cannot be installed or removed without disassembling other components. The utility model makes some improvements to the prior art. SUMMARY OF THE INVENTION The purpose of the present invention is to provide a T-slot convenient bolt with simple structure and convenient mounting and dismounting for the current situation that the existing T-slot bolts are inconvenient to install and disassemble.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: furniture and furniture screws, thick washer washers, two combination hexagon head bolts, GB873 hollow core nylon rivets and other products, we can provide you with The right fastener solution for you.
