Lubrication mechanism in gearbox of high-speed railway trains

Abstract

Lubrication of gearbox has been studied by many investigators using experimental, analytical, and numerical methods. Changenet and Velex (2006) derived a series of formulae that can accurately predict the churning losses for one pinion characteristic of automotive transmission geometry based on experimental analysis over a wide range of speeds, gear geometries, lubrications, and immersion depths. Laruelle et al. (2017) provided a wide variety of experimental tests on churning losses to find out the impact of speed, lubricant, temperature, and gear geometry on splash lubrication power losses. An extended equation was then developed from the experimental results to estimate churning losses of bevel gears. Leprince et al. (2012) set up a test rig to measure the quantity of lubricant splashed at different locations on the casing walls and deduced a set of formulae based on the experimental results to predict the lubricant flow rate generated by one spur gear at various places on the casing. Chen and Matsumoto (2016) performed oil churning loss experiments to clarify the influence of the relative position of gears and casing wall shape of gearbox under splash lubrication condition. They concluded that in addition to the well-known factors, relative position, casing wall shape, and the steady-state oil surface also had significant effects on the churning loss. Liu et al. (2012) suggested a new lubricant and measured the transmission efficiency, bulk temperature, and gear tooth scuffing at four different immersion depths. A range of reasonable immersion depths was obtained from that research. Neurouth et al. (2017) also followed an experimental approach to decide if splash lubrication technique is worth considering for high-speed gears (i.e. for tangential gear speed up to 60 m/s). The researchers used a specific test rig to operate a single spur or helical gear in various operation

Comparison of performance between tapered and cylindrical roller bearings for pinion of gear unit subjected to rotation test

“…Liu et al 10 proposed and verified a prediction model of bearing temperature of gear unit anomalies based on bi-directional long short-term memory. Deng et al 11 modeled the behavior of the lubricating oil inside the railway gear unit and obtained the churning losses as a source of heat generation by calculation. While these studies are useful for estimating the temperature of the entire gear unit, the bearings are simplified as a single element in their models and are insufficient to verify the thermal properties of the bearings.…”

Research on Splash Lubrication Characteristics of a Spiral Bevel Gearbox Based on the MPS Method

“…Based on these findings, combined with the experimental results provided in references [6,20], it can be pointed out that both the MPS and SPH methods can be used to predict the oil distribution, but the churning loss obtained by the MPS method is more accurate than that determined by SPH. Deng et al [24] and Xie et al [25] established highfidelity numerical simulation models for gearboxes used in different types of rail vehicles and carried out simulation calculations with different speeds and lubricating-oil volume levels and viscosities, providing a precedent for the engineering application of the MPS method. The simulation model they established retained the complex gearbox structure, and the modeling process was very simple.…”

Dynamic simulation analysis and experimental study of an industrial robot with novel joint reducers

“…This new reducer coverts sliding friction to rolling friction during the gear engagement with the replacement of gear teeth with rollers, thereby reducing the tooth wear and increasing transmission efficiency and accuracy. This type of reducer has a wide array of potential applications including joint reducers for industrial robots, turning centers of CNC machines, and gearboxes of high-speed railway trains [25]. While manufacturing methods and lubrication mechanism of ZHPRER have been thoroughly investigated by Deng and coworkers [26][27][28][29][30][31], the applicability of such reducers in the industrial robots remains unstudied.…”