1) Scope This standard specifies the size of the lock nut (referred to as the nut), the locking device, technical requirements, acceptance rules and measurement methods. This standard applies to the design, production, inspection and user acceptance of tapered bushing nuts and locking devices.
2) Terminology The terminology used in this standard conforms to the provisions of GB/T 6930.
This standard specifies the marking system, indexes, test methods and signs for the mechanical and working performance of the effective moment type steel hexagonal locking nut. This standard applies to carbon steel or alloy steel, the width of the opposite side of GB 3104, nominal height ≥ 0.8D, required to ensure that the specified load and effective torque, threaded diameter of 3 ~ 39mm coarse teeth 6H class nuts. In addition to the effective torque portion, its thread size and tolerances are specified in GB 193, GB 196 and GB 197. The working temperature range of the nut should be in accordance with: All-metal nuts without plating: -50°C to +300°C.
All-metal nuts treated by electroplating: -50°C to +230°C; nuts embedded in non-metallic elements: -50°C to +120°C. This standard does not apply to nuts with special performance requirements (such as welding performance and corrosion resistance). Fine tooth locking nut or thin nut made of carbon steel or alloy steel for stainless steel and non-ferrous metals, the agreement and the testing method of the effective torque specified in this standard can be adopted by both parties.