However, this process scheme has high cost, low efficiency, and has certain difficulties in quality assurance. In order to ensure product production efficiency, reduce manufacturing costs and improve product quality, it must be considered that the blank forming is completed on a multi-station cold heading machine at one time.
Gaskets are primarily used to protect the bearing surfaces of the coupled pieces. Bolts, nuts, etc. are mostly made of medium carbon steel, and alloy steel is also used. When there are requirements for anti-corrosion or electrical conductivity, copper, copper alloy and other non-ferrous metals can also be used. The standards of China and many countries stipulate that threaded joints are graded according to their mechanical properties, and the grade code is marked on the fastener. The rivet is made of steel, aluminum alloy or copper alloy, etc., and the head has various shapes to meet the needs of different rivet seams.
Pre-embedded channels are often used in rail transit. There are usually U-shaped channels and C-shaped channels. There are also various widths of openings on one side. The T-bolts used in their connection are generally non-standard parts, which need to be The actual project needs to be customized, mostly for the overall stamping production, the mold cycle is long, the number of mold openings is large, and the production cost is high. Moreover, when assembling and connecting, it is sometimes found that the size of the originally designed t-bolts does not match, and it is necessary to replace t-bolts of different sizes, then it is necessary to redesign and produce non-standard t-bolts, which slows down the entire equipment. processing cycle. Customized T-bolts are often not wide enough in size range, and only a few can be selected for specific assembly and connection, which is difficult to meet the diverse requirements of the production site for bolts.
T-bolts for channel steel usually include a head and a shank. The shank is provided with threads. Traditional T-bolts for channel steel are used for channel steel, and both channel steel and bolts are made of steel. , the two are prone to thermal expansion and contraction due to changes in the external ambient temperature, and are prone to loosening, resulting in unstable connections.
1. The expansion phenomenon of the spring washer is generally not the problem of the spring washer itself. 2. The spring washer with the expansion ring must be subjected to a radial external tension. The external tension is derived from the tightening axial force generated by the tightening torque. The chamfer creates a radial component of the axial clamping force, which expands the opening of the spring washer. The smaller the chamfer diameter, the greater the possibility of ring expansion. 4. Adding a flat washer between the nut and the spring washer helps to slow down or prevent the expansion of the ring, but the flat washer is too thin or too soft. Prevent ring expansion 5. The reason for the hydrogen embrittlement fracture of spring washers is generally due to unreasonable heat treatment process and the failure of hydrogen removal treatment after electro-galvanizing. A large number of tests and long-term practical experience have confirmed the above analysis.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: high-strength socket head cap screws and nuts, blue and white round head bolts with washers, patterned circular step knurled nuts, cross recessed countersunk head flat head screws, etc. products, we can provide you with the right fastener solution for you.