Service HotlineThe difference between high-strength bolt friction type and pressure-bearing type connection: High-strength bolt high-strength bolt connection is to clamp the plate of the connecting plate through a large tightening pre-pressure in the bolt rod, which is enough to generate a large friction force, thereby improving the connection. The integrity and stiffness of the bolt can be divided into two types: high-strength bolt friction type connection and high-strength bolt pressure type connection according to different design and force requirements when subjected to shear force. The essential difference between the two is that the limit state is different, although It is the same kind of bolt, but it is very different in terms of calculation method, requirements, and scope of application. In the shear design, the friction type connection of high-strength bolts is the limit state when the external shear force reaches the possible maximum friction force provided by the bolt tightening force between the contact surfaces of the plates, that is, the internal and external shear force of the connection is guaranteed not to exceed maximum friction. The plate will not undergo relative slip deformation (the original gap between the screw and the hole wall is always maintained), and the connected plate will be elastically stressed as a whole. In the design of shear resistance, the external shear force is allowed to exceed the maximum friction force in the high-strength bolt-bearing connection. At this time, relative slip deformation occurs between the connected plates until the bolt rod contacts the hole wall, and then the connection depends on the bolt rod. The shearing of the body and the bearing of the hole wall and the friction between the contact surfaces of the plates jointly transmit the force, and finally the shearing of the shaft or the bearing of the hole wall is regarded as the limit state of the connection shearing. In a word, friction type high-strength bolts and pressure-bearing high-strength bolts are actually the same type of bolts, but whether the design considers slippage. Friction type high-strength bolts can never slide, and the bolts do not bear shear force. Once slipped, the design is considered to reach a state of failure, which is technically mature; pressure-bearing high-strength bolts can slide, and the bolts also bear shear force, and the final damage is equivalent to ordinary Bolt failure (bolt shearing or steel plate crushing).
kind of screw provided by Yueluo, the rod body of the screw rod has a thread segment, one end of the thread segment is provided with an annular convex ring on the outer peripheral surface of the rod body, and the distance between the convex ring at the front end of the screw threading direction and the rod core Smaller than the nominal size of the threaded section or the distance from the rear end of the bead to the rod core in the screwing direction is greater than the nominal size of the threaded section.
The existing automobile fastener nut is a common nut. After the nut is matched with the bolt, during the tightening or disassembly process, there will be a phenomenon of sliding wire, and the safety factor is relatively low; It is difficult to guarantee, easy to rust, requires frequent inspection and replacement, and increases the cost of using the car, which can no longer meet the needs of the market.
rivet assembly device is provided with a base, the middle of the base is provided with a vertical groove, the bottom wall of the vertical groove extends forward and a horizontal convex block is suspended; the top surface of the convex block is fixed with a vertical rivet Needle and a guide column, the column body of the guide column is covered with a return spring; a downwardly open sliding block is mounted on the convex block, and the upper ends of the rivet needle and the guide column respectively protrude into the sliding block on the top wall of the sliding block. In the riveting pin hole and the guide hole, the inner wall of the riveting pin hole is provided with a large upper and a lower small horizontal step; the upper part of the bottom wall of the vertical groove is provided with a guiding limit rib. Guangdong Yueluo Hardware Industrial Co., Ltd. sets the rivet needle under the workpiece, and uses the upper die punch to press down the workpiece, and the rivet needle completes the operation of the rivet, omitting the operator to turn over and carry the rivet terminal board, thus effectively avoiding the rivet from The phenomenon that the rivet hole comes out. In addition, during operation, the workpiece is placed on the top surface of the slider, and the workpiece guide limit ribs and guide columns are used as shafts and radial limiters respectively. The riveting quality is good, and the purpose of saving time and labor and high efficiency is achieved.
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 churchill cityT-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 churchill cityT-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.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: skeleton oil seal gaskets, extended cup head cylinder head screws, external hexagon concave head churchill cityflange bolts with teeth, Q194 screws and other products, we can provide you with products such as Provide the right fastener solution for you.
