Service HotlineSeveral concepts about high-strength bolts 1. According to the specified performance level of bolts above 8.8, they are called high-strength bolts. The current national standard only lists M39. For large-size specifications, especially those with a length greater than 10 to 15 times High-strength bolts, domestic production is still short-term. The difference between high-strength bolts and ordinary bolts: High-strength bolts can withstand larger loads than ordinary bolts of the same specification. High-strength outer hexagon bolts High-strength outer hexagon bolts are made of Q235 (ie A3). The material of high-strength bolts is 35# steel or other high-quality materials, which are heat-treated after being made to improve the strength. The difference between the two is the difference in material strength. From raw materials: High-strength bolts are made of high-strength materials. The screws, nuts and washers of high-strength bolts are all made of high-strength steel, such as No. 45 steel, 40 boron steel, 20 manganese titanium boron steel, 35CrMoA, etc. Ordinary bolts are usually made of Q235 (equivalent to A3 in the past) steel. In terms of strength grades: high-strength bolts are increasingly used. Two strength grades are commonly used, 8.8s and 10.9s, of which 10.9 is the majority. The strength level of ordinary bolts is lower, generally 4.4, 4.8, 5.6 and 8.8. High-strength bolts High-strength bolts are viewed from the force characteristics: high-strength bolts apply pretension and transmit external forces by friction. Ordinary bolt connection relies on the shear resistance of the bolt and the bearing of the hole wall to transmit the shear force. When the nut is tightened, the pre-pressure is very small, and its influence can be ignored. In addition to its high material strength, high-strength bolts also exert a large amount of pressure on the bolts. The pre-pressure generates extrusion force between the connecting components, so that there is a large friction force perpendicular to the direction of the screw, and the pre-pressure, anti-slip coefficient and steel type directly affect the bearing capacity of high-strength bolts. According to the force characteristics, it is divided into pressure type and friction type. The calculation methods of the two are different. The minimum specification of high-strength bolts is M12, and M16~M30 are commonly used. The performance of super-large bolts is unstable and should be used with caution in design.
The structure of Guangdong Yueluo Hardware Industry Co., Ltd. is as follows. Figure 1 is a schematic diagram of the structure of the existing pin shaft stop mode of a general excavator. Figure 2 is a schematic structural diagram of the pin shaft stop used by Guangdong Yueluo Hardware Industry Co., Ltd. for applying the bolt of Guangdong Yueluo Hardware Industry Co., Ltd. Fig. 3 is the left side view according to Fig. 2 of the bolt used for pin stop by Guangdong Yueluo Hardware Industry Co., Ltd. Fig. 4 is the front view of Guangdong Yueluo Hardware Industrial Co., Ltd., which is used for the pin shaft stopper to insert the pin into the pin and form the pin of the pin structure. Fig. 5 is the left side view of Guangdong Yueluo Hardware Industry Co., Ltd., which is used for the pin shaft stopper to insert the pin into the pin and form the pin of the pin structure. Fig. 6 is a front view of the bayonet of the latch used for pin stop by Guangdong Yueluo Hardware Industry Co., Ltd. Fig. 7 is a top view of a bayonet of a latch used for pin stop by Guangdong Yueluo Hardware Industry Co., Ltd. Fig. 8 is the front view of the circlip of the latch used by Guangdong Yueluo Hardware Industry Co., Ltd. for pin stop. [0017] FIG. 9 is a top view of the circlip of the bolt that Guangdong Yueluo Hardware Industrial Co., Ltd. is used for pin-stopping. In Figures 1 to 9, the latch (1), the retaining sleeve (2), the pin shaft (3), the bayonet (4), the circlip (5), the misaligned through hole (6), and the misaligned end head (7).
Since the HDS series is a disc spring that can be folded or overlapped. The combination of the butt joint can increase the deformation of the disc spring group, and the combination of the overlapping method can increase the spring force of the disc spring group. The ideal installation method is to flatten as much as possible. The closer it is to the flattened state, the faster the tension torque increases, and the proper bolt tension can be obtained without a torque wrench.
screw generally includes a screw head, a screw part and a screw tail. In the traditional screw processing, the screw head and the screw part are punched out first, and then the threaded part is processed on the screw shank through the turning process. When the screw head is traditionally punched, the screw head is easily damaged due to the large punching force.
Combination bolts refer to a bolt with a spring washer and a flat washer, which are combined by rubbing teeth. Before the combination bolt is used, the bolt, the spring washer and the flat washer are generally combined by a specific machine. The combined production line mainly includes the processes of feeding, discharging, feeding, charging, screwing and tightening. The existing combined bolt production equipment mainly transmits the bolts to each process through the conveyor belt, and finally completes the combined assembly. The machines in each process are scattered and the space is occupied. The vibrating plate feeding generally puts the bolt head up, and its bolts, spring washers, etc. After the flat pad is assembled, the fixation is poor, and it is easy to fall off during the assembly process.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: through-hole hollow long nuts, sealing washers, DIN137A, circular sealing rings and other products, we can provide you with suitable fastener solutions for you .
