The national standard for the size of the screws in the round head three-combination screw is GB818. The main technical requirements of various types are: iron and stainless steel for material requirements, low, medium and high carbon steel for iron, and stainless steel combination screws The materials are stainless steel 201, stainless steel 304 and stainless steel 316. The thread tolerance is 6G, and the mechanical properties of the iron combination screws are 4.8 and 8.8. The 4.8-level combination screws are ordinary steel, and the maximum allowable hardness is 255HV. The 8.8-level combination screws are generally made of wire rod 10B21. , and then undergo hardening treatment, and then dehydrogenation after hardening treatment. Hydrogen removal is to prevent hydrogen embrittlement of the spring washer in the combination screw. Prevent the spring pad from breaking. The tolerance class of the combination screws is A. The cross groove is H-shaped. The surface treatment of the combination screw has environmental protection and non-environmental protection. Such as, environmental protection blue zinc, environmental protection color zinc, black zinc, color zinc, white nickel and so on. The technical requirement of the combination screw for the spring washer is that the washer should be able to rotate automatically without falling off.
An asphalt pavement screw, the asphalt pavement screw includes a main rod, an outer jacket, a pressing piece and a nut, the main rod is a columnar rod, the lower end of the main rod is provided with a table for supporting the outer jacket, and the middle part of the main rod passes through the outer jacket The upper part of the main rod is provided with a threaded section, the pressing piece and the nut are set on the threaded section, and at least two deformation holes are provided on the outer sleeve, and the middle part of the deformation hole is larger than the upper and lower sides of the deformation hole, The part between the adjacent deformation holes is the deformation part, and the width of the middle part of the deformation part is smaller than the width of the upper and lower sides of the deformation part. After the asphalt pavement screw of Guangdong Yueluo Hardware Industry Co., Ltd. is assembled, it has strong bonding force with the asphalt road. Even if it is hit, it will not be separated from the asphalt road. Using this asphalt pavement screw to fix the road railing can strengthen the road railing. The firmness of the assembly.
The traditional dismantling of automobile girder rivets is mostly carried out manually, which has many defects such as long disassembly time, low disassembly efficiency, labor-intensive, time-consuming, labor-intensive, low operation safety, difficult protection, and easy injury.
Hexagon socket head cap screws are indispensable industrial necessities in daily life and have important tasks in industry. But ordinary hexagon socket head cap screws must be installed and disassembled with special tools. For ordinary users, some simple disassembly and maintenance work are often unable to be handled due to lack of tools.
Stainless steel usually refers to steel that has the ability to resist corrosion by air, water, acid, alkali salt or other medium. Depending on the alloy composition, the focus is on rust resistance and acid resistance. Although some steels are rust-resistant, they are not necessarily acid-resistant, and acid-resistant steels are usually rust-resistant. Austenitic stainless steel is mainly used in the production of fasteners. In people's daily life, the stainless steel often referred to is also austenitic stainless steel. The stainless steel fasteners we use are mainly made of austenitic 302, 304, 316 and low nickel 201 as raw materials.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: Torx countersunk head screws and bolts, DIN6799 open retaining rings, carbon steel four-jaw nuts, flat nuts and other products, we can provide you with suitable tightening screws for you. Firmware Solutions.