Process analysis of heat treatment of chain plates using high-frequency induction heating equipment

The transmission of oil drilling rigs widely uses chain transmission, which has the characteristics of fast transmission speed (8-20m/s), high power, strong carrying capacity (more than tens of tons), frequent load changes, and large inertial impact force. Therefore, its working conditions The harsh conditions put forward high requirements for material selection and heat treatment. Sleeve roller chains are composed of sleeves, chain plates, rollers, pins, etc.

The chain plate mainly bears the effects of alternating normal tensile stress and bending stress, as well as multiple impact loads. The maximum stress area at the empty plate is located at the edge of the hole inclined 70°-75° from the longitudinal axis of the link plate, which is easy to Fatigue cracks occur here, so it is required to have high fatigue strength and multi-impact resistance. In order to meet the needs of its work, we often use high-frequency induction annealing equipment for heat treatment, and the effect is very good. Next, let’s take a look at the high-frequency heat treatment process of the chain plate.

The technical indicators of the chain plate after heat treatment with high-frequency induction heating equipment are: 35CrMo steel is 42-47HRC, 42CrMo steel is 38-48HRC, and the surface has no oxidation and decarburization. According to the technical requirements of the chain plate, using medium-carbon low-alloy steel for medium-temperature tempering can fully meet its specifications. The heat treatment process is shown in the table below.

The chain plate after medium temperature tempering has good elasticity and high fatigue strength. In order to improve its service life, it is necessary to use steel balls or conical punches to extrusion and harden the inner hole. The greater the interference of the extruded hole, the greater the interference. The higher the fatigue strength of the chain plate, when the relative interference is 0.02mm, the fatigue strength is the highest, and the surface roughness, microhardness, reinforcement layer depth, etc. are all in a good state.

This article briefly introduces the high-frequency heat treatment process of the link plate in the sleeve roller chain. If you want to know the heat treatment process of other components, you can read books on heat treatment. I believe you will gain a lot.