The Analysis Of The Screw Conveyor Of The EPB Shieldand Study Countermeasures

During the construction of urban underground rail construction,the screw conveyor of EPB achieve shield soil compartment packing function and tapping functions,not only conveying the muck that cutter cutting to the ground,but also through the screw conveyor can maintain the pressure balance of tunnel face,and stability the tunnel face.That can effectively control the ground subsidence,prevent the surface collapse caused by construction of EPB,thereby reducing the ground collapse problem caused by the construction of the subway tunnel construction in city.Master the functional principle,fault type and structural design features of screw conveyor,to improve the technical level of large-scale machinery and equipment,has important engineering value and strategic significance.What is more,it also is the future large-scale Shield and micro Shield inevitable trend in China.Shield industry in the rapid development and application stage in our country,therefore,detection and analysis the screw conveyor of EPB in engineering practical application has great significance to master the key technologies of shield.Based on the above practical engineering background,this paper mainly detection and analysis of faults that screw conveyor system for EPB arise in practical engineering application.First of all,based on the key role of screw conveyor in EPB,analysis the principle and function of the screw conveyor in EPB construction.Secondly,according to the screw conveyor in EPB construction in practical application,analysis of the main screw conveyor fault condition occurs in the application process,and statistical analysis of the fault situation,there are major fault occurs that screw conveyor tube wall worn out(including a first cylinder wall and the second cylinder wall),helical blade worn or cracked,the screw shaft breaking,hydraulic oil contamination,lubrication oil pollution and so on.To targeted service the screw conveyor of EPB aimed at the damage occurring in construction,under the premise of ensure the two functions that screw conveyor in earth pressure balance as well as the fault characteristics and function of screw conveyor,to give the screw conveyor a targeted maintenance,and applied to the actual construction,ensure that the main function of the screw conveyor.Analysis of conventional design features of the screw conveyor,and to optimize the design of screw machine for improve the wear resistance of screw conveyor and prolong the life of screw machine.Using segmented design principles,to optimize the design based on packing and tapping features of the shield screw machine.According the wear condition of screw machine,to segment design the pitch of the screw shaft of screw conveyor,control the cylinder pressure of screw machine,thereby controlling the wear,distributing the pressure,and distributing the wear.So that to achieve uniform wear and extend the service life of the screw conveyor.