Of Key Technical Parameters Of The Full Hydraulic Study

In this paper, the history, the current situation and the developing trend of the traveling hydraulic system of the hydrostatic bulldozers are researched both inside and outside our country. The key parameters of bulldozers' traveling hydraulic system, the slip ratio, the efficiency of the hydraulic system, power-to-weight ratio and force-to weight ratio, are studied. The matched formula for computing the efficiency of the pump and the motor and the effect of the efficiency on the controlling objective are of much value in the practice. The means of the force-to-weight ratio is 1.48, the power-to-weight 1.72 KW/T, and the rated slip ratio 12-15%. Through the compare and analysis of the characteristics of the controlling patterns, hydraulic controlling, electronic controlling and hydraulic-electronic compound controlling, a controlling program suit for the whole hydraulic bulldozers has been got from the discussion. Two measures to prolong the working life of the hydraulic system are put forward followed the research on the pressure fluctuation of the machine caused by the varying load on it. As to the sample machine, the rated slip ratio and the power-to-weight ratio are bigger than the standard and the force-to-weight ratio is a little bit lower than the standard. The CAD of the whole hydraulic bulldozer, helpful for the design of the hydraulic system, has been developed, combined with the research on the driving capability. The developed software can output needed curves of the efficiency for a series of pumps and motors, besides the function to calculate the key parameters and draw the curve of the driving characteristic, which is of great practical valuation.