Study On Energy Saving Characteristics Of Hydraulic Control System For Driving Cuting Disc Of Earth Balance Shield

Earth pressure balance shield machines(short for EBM) were used widely in subway building in big city like Beijing, Shanghai, Shenzhen and many other cities. The principle of work is as below: the soil is excavated while EBM’s rotary cutting plate rotating. The excavated soil gathers and fills the mud bin which is under pressure. The screw conveyor continuously regulates the amount of the excavated soil as soon as the pressure over the sensor’s set up, and its removal from the mud bin(control of soil pressure) and removes the soil into the tunnel. The excavated solid material is transferred by aboveground equipment such as muck van or belt-transfer. The push cylinder will spread and push the whole equipment forward.The main of the paper is analysis energy saving of the closed loop circuit hydraulic system for the EBM’s rotary power, according to three kinds of the working condition. This paper uses a lot of real number, charts, and pictures to introduce the performance of this hydraulic power system of cutting disc. The main of the system is consisted of three Hydrokraft transmission piston pump and six variable displacement motors, this closed loop circuit system is saving more energy compare to the open circuit system, and its efficiency is improved 20% by using the load sensitive pump and variable displacement motor. It will provide a proportional displacement to the pressure signal in order to reduce the consumption of the energy.