Service HotlineThe traditional single-sided riveting process mainly adopts two methods: rivet nut connection and blind rivet connection. The efficiency of the rivet nut is low. If the hollow nut is used, the rigidity is insufficient, resulting in low connection strength. In addition, the torsion resistance of the rivet nut is low. If the rivet nut is used to obtain better torsion resistance, it is made into a hexagonal shape. Embedding, because the shape of the sheet metal opening also needs to be made into a corresponding hexagon, it is inconvenient to process.
1. When the main body is large-scale equipment, accessories need to be installed, such as sight glass, mechanical seal seat, deceleration frame, etc. The stud bolts used at this time, one end is screwed into the main body, and the other end is equipped with nuts after the accessories are installed. , Since the accessories are often disassembled, when the main body and the accessories are directly connected by bolts, the main body threads will be worn or damaged over time, and it is very convenient to use studs to replace them. 2. When the thickness of the connecting body is very large and the bolt length is very long, stud bolts will be used. The purpose of anti-loosening of stud connection In actual work, the external load has vibration, change, high temperature creep of the material, etc., which will reduce the friction force, the positive pressure in the thread pair disappears at a certain moment, and the friction force is zero, thus making the threaded connection loose. , if repeated action, the threaded connection will loosen and fail. Therefore, it is necessary to prevent loosening, otherwise it will affect the normal work and cause accidents.
During assembly, the washer and the screw are two separate parts, and the washer needs to be put on the connection part of the screw, which increases the workload of people during assembly, and the washer is easy to slip off; and some screws are fixed with Although the washer can reduce the workload of people during assembly, the washer is fixed on the screw, and the original function of the washer is limited.
As shown in Figures 1 and 2, Yueluo is an automatic locking screw. From bottom to top, there are screw head 1 with external thread, screw rod and nut 3. The screw rod is a hollow screw rod 2, and the hollow screw There are long holes 7 on both sides of the rod 2, the width of the long hole 7 is smaller than the inner diameter of the hollow screw rod 2, and a spring 4 is arranged in the inner cavity of the hollow screw rod 2, and the spring 4 is not smaller than the hollow screw rod 2 in the free extension state. The upper end of the spring 4 is provided with a plug 5, the distance between the two wings 6 of the plug 5 is greater than the diameter of the nut 3, and the two wings 6 of the plug 5 protrude out of the hollow screw rod 2 through the long hole 7. When using the Yueluo, you only need to compress the spring through the two wings, insert the U-shaped clip after the neutral position is exposed, and then release the two wings, the spring will automatically return and compress the U-shaped clip, which is easy to use, safe and reliable. Claim 6. An automatic locking screw, from bottom to top, is a screw head, a screw rod and a nut provided with an external thread, characterized in that the screw rod is a hollow screw rod, and both sides of the hollow screw rod are respectively provided with Long hole, the width of the long hole is smaller than the inner diameter of the hollow screw rod, the inner cavity of the hollow screw rod is provided with a spring, the upper end of the spring is provided with a plug, and the two wings of the plug protrude out of the hollow screw rod through the long hole.
Several 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.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: Dongguan non-standard nuts, rivets, step bolts, flat head flat cup bolts and other products, we can provide you with suitable fasteners for you solution.
