Service HotlineThe purpose of this utility model is to solve the problems in the prior art, and proposes an installation structure which adopts T-bolt and groove matching, which can make the installation of the bolt more convenient, the degree of tightening is higher, the service life is longer, and the Routine replacement and maintenance.
In the automobile industry, it is often necessary to install bolts at the opening of a closed cavity to fix and connect other parts. However, the diameter of the opening of the closed cavity is often larger than that of the head of the bolt, so it is necessary to set a strip-shaped spacer on the head of the bolt, so that the spacer can penetrate the opening longitudinally, and then block the opening horizontally, so as to be stuck with an upside-down buckle. Bolt head. However, since the bolt body of the bolt has a certain length, the manual vertical and horizontal turning operation after the strip spacer penetrates the opening is very difficult, and it is easy to drop the bolt and the spacer into the airtight cavity together, which greatly increases the assembly time. Increased labor costs.
Screw (pinyin: luógǎn, English: screw): a cylinder with a spiral groove cut on the outer surface or a cone cut with a tapered spiral groove. The screw has a different head, the head is called an external hexagon screw. There are others, such as large flat screws, socket head screws and so on.
In 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.
Material and process requirements The self-tapping locking screw should be made of high-quality carburized steel cold heading, generally no larger than M12. The finished material should be drawn with a high total reduction rate before cold heading, so that the cold heading must be spheroidized. Annealing, in order to enhance the surface hardness and the toughness of the core, most of them are made of medium and low carbon steel. The chemical composition of the material in the standard is only for guidance. The C content is 0.13%~0.37%, the Mn content is 0.64%~1.71%, and the B content can reach 0.005%. The elements of S, P, Mn and Si in the commonly used steel are generally lower than those of the ordinary bolt steel of the same grade. And the surface quality of the material is strictly controlled to reduce deformation resistance and prevent deformation and cracking. Commonly used grades are 20Mn, 15MnB, SWRCH22A, 1022A and medium carbon steel, medium carbon alloy steel SWRCH35K, SCM435, SCR435, etc. Self-tapping locking screws are threads with an arc-shaped triangular cross-section, so the formulation of cold heading and wire rolling processes, as well as the design and manufacture of cold heading dies and special rolling plates are very important. Self-tapping locking screws require a high-hard surface for cutting and extruding capabilities due to the need for self-tapping low carbon steel. At the same time, there must be sufficient core strength and toughness to prevent twisting and breaking during work. The heat treatment process of this type of screw belongs to shallow carburizing. Regardless of whether it is made of low carbon steel or medium carbon or medium carbon alloy steel, its core hardness must be guaranteed to be within the range of 28~38HRC (9.8 grade) 33~39HRC (10.9 grade) and not less than the minimum tensile load of 930MPa (9.8 grade), 1040MPa (grade 10.9), depending on the material, the minimum tempering temperature is 420℃. In order to ensure that the self-tapping locking screw can be smoothly screwed into the prefabricated cylindrical hole, the end of the screw should be hardened by high-frequency quenching to ensure that at least one to three thread teeth are hardened, and the minimum surface hardness is 45HRC.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: black set bolts, fastening fastener bolts, rear-mounted cage nuts, elevator connection nuts and other products, we can provide you with suitable products for you. Fastener Solutions.
