Fatigue strength improvement of roller chain by press fitting between pin and plate

To improve the fatigue strength of the roller chain, the fatigue test is conducted by varying the press-fitting ratio between the pin and the holed plate. To model what occurs in a chain under load, a single plate specimen is prepared by press-fitting two pins into two holes at the ends of the plate. The FEM analysis is performed to obtain the stress amplitude and the average stress. The results, in both cases demonstrate that the fatigue strength is improved by the press-fit between the pin and the hole. The fatigue improvement mechanism is discussed based on the stress analysis.

Efficiency Estimation of Roller Chain Power Transmission System

In the present study, a novel approach to estimating the efficiency of roller chain power transmission systems is proposed based on sliding friction losses and damping force. The dynamics model is taken into account between chain links with lateral offset owing to the derailleur system. Frictional losses were calculated according to Coulomb’s law of friction, and the damping force was dependent on the damping coefficient. The effects of rotational speed, load, derailleur system, and damping coefficient on transmission efficiency were analyzed. The test stand of the roller chain power transmission system was set up to verify the estimated efficiency, and the results showed a good correlation, demonstrating the validity of the chain power transmission efficiency estimation.

Measurement of roller chain wear lubricated with palm oil-based hexagonal boron nitride nanoparticles

Purpose This study aims to introduce a novel technique which helped in quantifying the wear performance of a roller chain which was lubricated by using the palm oil-based hexagonal boron nitride (hBN) nanoparticles (nano-biolubricant). Design/methodology/approach The efficiency of the nano-biolubricant was evaluated by using a custom-made roller chain tribometer, at different resistance torque values at a constant speed and running time. Prior to the test, 2 different lubrication conditions were applied. The mass loss and elongation behaviour of a roller chain was selected as a degradation metric for monitoring the amount of the chain wear. The predominant wear mechanism of a roller chain was identified by surface morphological analysis. Findings Regardless of the lubrication conditions, the wear performance of the roller chain was significantly increased, at increasing resistance torque values. Higher wear was noted when the roller chain was lubricated using a nano-biolubricant, however, the wear curve showed a promising high chain life. The predominant wear mechanism involved is abrasive wear. Originality/value Although an increase in the elongation during running is based on the wear between the pins and roller, none of the earlier studies quantified the wear performance of a roller chain under differing lubrication conditions. Hence, for bridging the gap, this study described a new method for measuring the wear performance of the roller chain which was lubricated using the palm oil-based hBN nanoparticles or a nano-biolubricant. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2020-0061/