Adjustment of chain drives with a toothed chain and involute sprockets

Abstract

Chain drives with a toothed chain have a wide application both in vehicles and in oil-refining equipment. The proposed method of calculation of chain drives with a toothed chain and involute sprockets takes into account its operation conditions, pollution, load conditions, dynamic loads, operating environment, lubrication method, intrusion of grain materials etc. In order to keep it in good working order, recurring maintenance is conducted with chain drive adjustment being the most important condition. The paper offers recommendations on adjustment of a chain drive with a toothed chain and involute sprockets, based on the absence of the chain slip over the sprocket teeth. Chain drive adjustment levels and strand sag factors are defined. Results of calculations of the minimum angles of sprocket and toothed chain wrap with different numbers of sprocket teeth are obtained. Some dependencies are deduced in order to determine strand sag factors with possible transverse resonance oscillations produced by faceted sprocket and eccentricity. The results of calculation of the initial adjustment level for a chain drive with a toothed chain are presented, which is determined by the minimum driven strand sag factor, as well as the results of calculation of the final adjustment level for a chain drive with a toothed chain, which is determined by the maximum driven strand sag factor. These results exclude the possibility of occurrence of transverse resonance oscillations and slipping. The results obtained showed that in a two-shaft chain drive, adjusted by the proposed method, there will be no transverse resonance oscillations and slipping. The observance of the given recommendations on adjustment of chain drives with a toothed chain equipped with involute sprockets, will provide its operability.