Service HotlineScrew model Drive Code: groove on the head, characteristic model Length Code: screw length (mm) A-1: Thread Code: screw model Metric screws directly indicate the screw model with the outer diameter of the screw, such as M3, the outer diameter of the screw is 3.00mm. ; M4 means the outer diameter of the screw is 4.00mm. Metric Thread Size x Pitch: Note: The metric screw is behind the screw model, and sometimes the screw pitch is indicated. Such as M3x0.5, M4x0.70, M5x0.8, M6x1. Standard specification, usually not mentioned. A-2: Length Code: Screw length: For metric screws, the screw length is directly marked in mm. The total length of the screw is marked, only the length below the head is calculated, excluding the head height. But With the exception of flat head screws, the total length of the screw is marked with the head height. A-3: Drive Code/ Head Groove, Features.
4. Manufacturing and assembly Due to the limitations of manufacturing technology and accuracy, there are sharp corners on the edge of the thread or the dimensional coordination between parts is not coordinated. During the initial assembly, the screw-in and screw-out torque may fluctuate or fluctuate to a certain extent. After a certain number of running-in, more accurate reusability characteristics of the lock nut can be obtained.
The product structure in the known technology includes a T-shaped bolt with a longitudinal section, and a polygonal nut matched with the bolt. The bolt is divided into two parts: the screw and the screw head. The screw head is placed at one end of the screw to form an integral part. The radial length of the tightening surface of the screw head is greater than the radial length of the screw, and its axial length is less than the axial length of the screw; The solid surface is a polygon, and now a hexagon is commonly used. The periphery of the base of the nut and the screw head has a number of elastic surfaces corresponding to the polygon; the periphery of the axial screw is provided with an external thread matching the internal thread of the nut. In actual use, the fastener of this structure can be tightened by using a conventional screw, such as a wrench. Therefore, its anti-theft performance is poor and it is not suitable for occasions with special requirements.
The gasket refers to the part between the connected part and the nut, which is generally a flat metal ring, which is used to protect the surface of the connected part from scratches by the nut and disperse the pressure of the nut on the connected part.
There are many types of T-bolts used with pre-embedded chutes, which are used for the connection of external components of pre-embedded chutes embedded in segments, U-beams, building concrete, etc. The fixing of the chute on the forming die. When producing segments and U-shaped beams, the embedded chute is fixed on the forming mold by T-bolts. During the concrete pouring process, the tightening nut is easily covered by concrete. In this way, the concrete on the fastening nut should be removed, but it is difficult to remove the concrete, which will cause inconvenience to the disassembly of the forming mold after the production of the segment and the U-shaped beam.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: high-strength galvanized, flat head machine screw, super-thick small edge flat washer, cross-recessed bolt and other products, we can provide you with suitable products for you. Fastener Solutions.
