The spring screw is a tool that uses the physical and mathematical principles of the oblique circular rotation of the object and the frictional force to fasten the machine parts step by step; the screw is a common invention in people's production and life for thousands of years. According to the application field, Screws have a wide range of applications.
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.
Anchor bolts can be divided into fixed anchor bolts, movable anchor bolts, expansion anchor anchor bolts and adhesive anchor bolts. According to the different shapes, it is divided into: L-shaped embedded bolts, 9-shaped embedded bolts, U-shaped embedded bolts, welded embedded bolts, and bottom plate embedded bolts.
Screw (English a screw) refers to the parts used in construction machinery. It is a kind of threaded parts with sharp ends such as nails, small cylindrical or conical metal rods, with grooved or dimpled heads, and used alone. . The detection of the screw should start from the wire of the screw. The quality of the precision screw is directly related to the wire that produces the screw. A good screw wire will open the screws more beautifully. What screw head burst, what thread is bad. Good screw wires generally do not find this situation.
Rivet nuts are mostly used in some chassis cabinets, square tubes and round tubes, fan production, equipment production, and zinc steel guardrails. Next, let’s talk about rivet nuts. The rivet nuts are also used on the top of the chassis cabinet sheet to provide threads. Its mode of operation is to use a riveting machine for riveting. In this case, the requirements will be higher, and a riveting machine is required. After the pressure riveting nut is riveted to the upper side of the sheet, it is very flat and will not have protrusions. Pressure riveting nuts are mainly used in the production of some chassis and cabinets, as well as some equipment production, water pumps, automobiles, and other production enterprises.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: solid wood connections for accessories, 4.8 grade spring washers, DIN546 slotted round nuts, black hardened hexagon countersunk head screws and other products, we can provide you with The right fastener solution for you.