What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
Yueluo's thin plate rivet method, the thickness of the metal thin plate is less than 0.8mm. The convex rib extrudes the metal sheet adjacent to the rivet hole. The protruding rib is annular, and the protruding rib surrounds the rivet. The rivet head is provided with a positioning structure, the rivet head is provided with a positioning structure for docking the positioning structure, and the positioning structure and the positioning structure are mutually butted through the rivet to align the convex rib with the rivet
Fasteners such as bolts and rivets are called the rice of industry, and they are used in infrastructure construction, equipment machinery, automobile manufacturing, electronic information, aerospace and other industries. According to the mechanical properties of fasteners, fasteners are divided into high-strength fasteners and ordinary fasteners. At the end of the 20th century and the beginning of the 21st century, with the rapid development of the economy, the demand for anti-seismic and anti-loose fasteners surged. Although the fasteners are small, their quality and reliability play an important role in the performance and structural safety of the main engine. Incredible.
1. Fixed anchor bolts, also known as short anchor bolts, are poured together with the foundation and used to fix equipment without strong vibration and impact. 2. The movable anchor bolt, also known as the long anchor bolt, is a detachable anchor bolt used for fixing heavy machinery and equipment with strong vibration and impact. 3. Expansion anchor bolts are often used to fix stationary simple equipment or auxiliary equipment. The installation of expansion anchor bolts should meet the following requirements: the distance from the center of the bolt to the edge of the foundation shall not be less than 7 times the diameter of the expansion anchor bolt; the foundation strength of the expansion anchor bolt shall not be less than 10MPa; there shall be no cracks in the drilling holes. The drill bit collides with the steel bars and buried pipes in the foundation; the diameter and depth of the drill hole should match the expansion anchor bolts. 4. The bonding anchor bolt is a kind of anchor bolt commonly used in recent years, and its method and requirements are the same as the expansion anchor anchor bolt. However, when bonding, pay attention to blowing out the debris in the hole, and do not get wet. [1]
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.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
