Service HotlinePin riveting is an important procedure in the production process. At first, people used manual work, which has low production efficiency, high production cost, and high defect rate of products produced. Later, a pin riveting machine appeared. The pin riveting machine is a For riveting and pinning of hardware products, the pin riveting machine can complete the operation of pin loading and riveting pins, and the pin riveting machine reduces the process of pin loading and riveting pins in the hardware production process. However, its structural design is unreasonable and the operation is very inconvenient
When the countersunk head screws and hexagon socket head bolts are produced by the cold heading process, the original structure of the steel will directly affect the forming ability of the cold heading process. In the process of cold heading, the plastic deformation of the local area can reach 60%-80%, so the steel must have good plasticity. When the chemical composition of the steel is constant, the metallographic structure is the key factor to determine the plasticity. It is generally believed that the coarse flaky pearlite is not conducive to cold heading forming, while the fine spherical pearlite can significantly improve the plastic deformation ability of the steel. For medium carbon steel and medium carbon alloy steel with a large amount of high-strength bolts, spheroidizing (softening) annealing is performed before cold heading, so as to obtain uniform and fine spheroidized pearlite to better meet the actual production needs. For the softening annealing of medium carbon steel wire rods, the heating temperature should be kept above and below the critical point of the steel, and the heating temperature should not be too high, otherwise tertiary cementite will precipitate along the grain boundary, resulting in cold heading cracking. The wire rod of medium carbon alloy steel is annealed by isothermal spheroidization. After heating at AC1+ (20-30%), the furnace is cooled to slightly lower than Ar1, the temperature is about 700 degrees Celsius for an isothermal period, and then the furnace is cooled to about 500 degrees Celsius and air-cooled. The metallographic structure of the steel changes from coarse to fine, from flake to spherical, and the cracking rate of cold heading will be greatly reduced. The general area of softening annealing temperature for 35\45\ML35\SWRCH35K steel is 715-735 degrees Celsius; while the general heating temperature for spheroidizing annealing of SCM435\40Cr\SCR435 steel is 740-770 degrees Celsius, and the isothermal temperature is 680-700 degrees Celsius.
1) Scope This standard specifies the lock nut (referred to as nut), the size of the locking device, technical requirements, acceptance rules and measurement methods. This standard applies to the design, production, inspection and user acceptance of nuts and locking devices for tapered bushings. 2) Terminology The terms used in this standard conform to the provisions of GB/T 6930. This standard specifies the marking system, index, test method and marking of the mechanical and working performance of the effective torque section steel hexagonal lock nut. This standard is applicable to coarse thread 6H class nuts made of carbon steel or alloy steel, the width across the sides conforming to the provisions of GB 3104, the nominal height is ≥ 0.8D, and the guaranteed load and effective torque need to be specified, and the thread diameter is 3 ~ 39mm. Except for the effective torque part, the thread size and tolerance are specified in GB 193, GB 196 and GB 197. The working temperature range of the nut should be in accordance with: All-metal nut without electroplating treatment: -50℃～+300℃. All-metal nuts with electroplating treatment: -50℃～+230℃; nuts embedded with non-metallic elements: -50℃～+120℃. This standard does not apply to nuts with special performance requirements (such as weldability and corrosion resistance). For stainless steel and non-ferrous metals with Portlandfine pitch lock nuts or thin nuts made of carbon steel or alloy steel, the performance indicators and test methods of effective torque specified in this standard may be adopted by mutual agreement.
The PortlandPortlandspring washer usually includes a washer body and a raised claw head punched and formed on the washer body. The PortlandPortlandspring washer is often placed between the bolt head of the bolt and the connected parts, wherein the raised claw head is connected to the part to be connected. The surfaces of the connecting parts are in contact, and the plane on the gasket body, opposite to the lifting direction of the raised claw head, is in contact with the bolt head. After the bolt head is tightened, the elastic reaction force generated by the raised claw head after flattening makes the The screwed threads are pressed tightly, and at the same time, the raised claw head is pressed against the bolt head and the supporting surface of the connected parts, which has the effect of preventing loosening. However, the traditional PortlandPortlandspring washer is a single-claw type. When tightening, the raised claw head will cause great damage to the surface of the connected parts, so it is not suitable for the anti-loosening treatment of parts with small surface hardness.
leak-proof combined gasket relates to a gasket and solves the problem of short service life of the existing gasket. The combined gasket comprises: an O-shaped sealing ring, which is an annular sealing ring with an outer diameter of D and an inner diameter of E. The section diameter is A; the steel outer ring is a steel flat annular outer ring, which is sleeved on the outer surface of the O-ring, the inner diameter is F, and F=D, the thickness is B, B=0.785A ;The steel inner ring is a steel flat annular inner ring, embedded in the inner surface of the O-ring, the outer diameter is G, and G=E; the thickness is C, and C=B. When the O-ring in the combined washer is pressed by the bolt for sealing, it is positioned between the steel outer ring and the steel inner ring, and is protected by both of them, so that the tightening torque of the bolt can be reduced at least Double the sealing performance without reducing the sealing performance, extending the service life of the thread and reducing the production cost.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: half crescent Portlandround washer nuts, extended flat head bolts, extended hexagon nuts, large head shrink rods and other products, we can provide you with suitable fasteners for you solution.
