Service HotlineIn the process of driving the car, it is inevitable to use the brake frequently, which will cause the gap between the brake drum and the friction pad of the car to become larger. Therefore, it needs to be adjusted in time, otherwise, the hidden danger of unsafe driving will be buried due to the excessive braking distance and the out-of-round brake drum. Therefore, motor vehicles must be equipped with automatic adjustment arms. In the existing automatic adjustment arm, the worm inside the housing is limited by the spring pad, the spring and the spring cover, and the end face of the spring pad is directly in contact with the worm, and the rotation of the worm is inflexible due to frictional resistance during rotation.
When fixing the centrifugal fan, since the gaskets, washers and nuts are separate parts, many parts are used in the whole process, and it is easy to miss the installation of parts; The volume of the parts is relatively small, and it is not easy to remove them when they are transferred into the air conditioner through the gap of the centrifugal fan blades, resulting in foreign bodies in the machine.
through-hole mounting nut, comprising a hexagonal portion 1 and a cylindrical portion 2, a threaded hole 3 is provided between the hexagonal portion 1 and the cylindrical portion 2, and two grooves 4 are opened on the cylindrical portion 2, and each of the two sides of the groove 4 has a The raised side 5, the two sides protruding from the sheet metal part 7, if squeezed or hit by the bolt 8, it will bend to both sides and buckle on the sheet metal part, so that it is not welded directly. Rubber can also be used. Each of the upper surfaces of the side edges 5 is provided with a convex point 6 so that the hammer will not slip when hitting.
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.
Fastening of such functional elements in flat gaskets is usually achieved by additional measures or by a special design of an additional, functional layer adjacent to the carrier layer, or by a special design of the parts to be sealed. Fastening the functional elements in this way is laborious and expensive, and is only possible for special gasket designs.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: round nuts, small hexagon head reaming bolts, GB39 square nuts, 8.8 high-strength hexagon nuts and other products, we can provide you with Provide the right fastener solution for you.
