In the maintenance rules formulated for the leaf chain, besides regular cleaning and lubricating oil addition, attention should also be paid to detecting and adjusting the vertical degree of the loose edge of the leaf chain, while ensuring its proper degree. Because of the vertical degree of the loose edge of the leaf chain is too high or too low, it will hinder the normal use of the leaf chain.

The adjustment shall be based on the actual operating conditions of the leaf chain. If the leaf chain is under vibration load and vertical transmission and moves in opposite directions, the verticality of the leaf chain will be smaller when it is under dynamic braking. However, if the leaf chain is tilted and horizontally driven to adjust the centre distance, then its sag should be kept at about 1%~2% of the centre distance.

The detection and adjustment of the vertical degree of the loose edge of the leaf chain is on the one hand, and on the other hand, it is about the handling skills after embrittlement of the leaf chain materials. In order to prevent the chain material from embrittling, a setting device can be added in the leaf chain, or a strip groove can be formed in the leaf chain upright post, and upper and lower chain feeders are respectively arranged at the upper and lower ends of the upright post.

The embrittlement of leaf chain material may be caused by incorrect carburizing and heat treatment process. It is also the result of analysis of stress, fracture, chemical composition, mechanical properties and metallographic structure of leaf chain.

In order to prevent such problems, on the one hand, the materials of the leaf chain should be carburized in the correct way; on the other hand, appropriate heat treatment process should be adopted to eliminate the adverse effects of various unfavourable factors on the leaf chain, thus reducing the probability of embrittlement.