Characteristic Analysis And Optimum Design Of Shield Cutter

As the fast development of Chinese cities,the faster manner of transportation and less traffic congestion are needed more and more,so shield machines are used more and more in the development of underground transportation.As the important part of shield machines for digging,the structure and rationality of fixing of the shield cutter is the important guarantee of stably and efficiently tunneling.This thesis has consulted lots of documents about the shield cutter,considering the geology of the project,designs the shield cutter of the EPB shield machine.After analyzing of the finite element stress to shield cutter,we have enhanced the structure of the shield cutter for the strength deficiency,and made the cutter arrangement more reasonable.The main point are as follows:(1)According to the geology condition of the working area of shield cutter,we choose the type of shield machine,and design the basic structure of the shield cutter.(2)Through analyzing the structure feature of shield cutter,especially analyzing the structure,the aperture ratio and the stirrer,we check the finite element stress of all conditions to the shield cutter.(3)Through analyzing of the finite element stress,we conclude that the maximum stress of shield cutter not meet the yield strength of material under maximum thrust condition,after optimizing its structure,we analyze and check again about all the situations of the finite element stress to the shield cutter again.(4)According to the geology condition of the working area of shield cutter,we choose slicer,tearing cutter and hob as the main cutter,and make better arrangement to the shield cutter.According to the geology condition of the project,we make characteristic analysis and optimum design of the EPB shield cutter,after force analysis,the maximum stress of the shield cutter is less than the set value of material yield limit315 MPa under the maximum thrust condition,eccentric load condition and extrication condition,and the maximum deformation value of the shield cutter structure is only2.6631 mm,so it meets the strength and stiffness requirements of the shield cutter.The3 D model of shield cutter is designed by using the track table of hob and scraper,the shield cutter is successfully manufactured,this thesis is good for technical staff of shield machine in cutter head designing.