Design Of Double Helix Cutting Head For XTR260 Hard-rock Boring Machine And Study On Its Cutting Characteristics

With the continuous construction of China's infrastructure.Highway,high-speed rail and other projects continue to increase,and there are large quantities of constructions of tunnels included,which leads to vastly increased demand of tunneling equipment.Boomtype tunnel road header has been widely used in mining,water conservancy,tunnel traffic,urban subway and other major engineering projects,due to its wide universality,wide scope of operation,reducing labor intensity effectively,high efficiency,shortening the project cycle and other advantages.At present,domestic boom-type road headers,mainly used in the coal mine roadway construction,can't be directly used in the tunnel construction,and there are few of boom-type tunnel road headers in our country,which causes the demand for tunnel construction can't be met.In order to meet the growing demand of tunnel constructions and breakthrough the foreign monopoly of market and technology,research and development on boom-type tunnel road headers are extremely urgent.Cutting head,being the core component of boom-type tunnel road header,has important effects on working reliability,efficiency,economy and other whole machine performance,therefore,its performance provides important references on the evaluation of machine performance.The design and research on cutting head is the top priority in the research and development of boom-type tunnel road header.However,it's still lack of scientific and systematic methods and routes on designing cutting head,which leads to high load,large differences of loads,big load fluctuation on picks,short and different lifetime of picks,high energy consumption and low efficiency and other bad results.It must be particularly stressed that there are few research on the cutting head of boom-type tunnel road header,which lack of theoretical foundation and test guidelines.A lot of problems,in cutting head geometry design,cutting parameters of single pick,arrangement of picks and key parameters etc.,are still left to solve.This paper based on the research project,according to the design and research of the cutting head,use the rock which solid coefficient f =10 and non-development as the cutting object,establish different three-dimensional models with Pro/E and submit them to ANSYS/LS_DYNA solver to solve.The purpose of designing and researching XTR260 cantilever hard rock tunnel boring machine cutting head is to find the best performance and design best parameters and reduce the cutting energy consumption and improve cutting head cutting efficiency,The main research contents are as follows:(1)Analyze the demand of domestic market,the development status and the research status of cutting head.Point out the insufficiency of the design and research of the cutting head of the tunnel boring machine.(2)Study the basic theory of cutting head design,to determine the helix number of the cutting head,the arrangement of the cutting arrangement,the kinematics analysis of the two working conditions of the cutting head,analyze the rock breaking process,Research cutting head force.(3)Study the rock cutting numerical simulation theory of cutting head and the mechanical properties of cutting rock and the failure criterion of rock material;introduce the algorithm and general steps of ANSYS/LS_DYNA software;do a detailed study on the double helix cutting head cutting rock simulation process.All work ensure the followup simulation can run smoothly and effectively.(4)Study the evaluation of cutting head cutting performance indicators.The numerical simulation of the four kinds of helical angle trimming cutting heads with the angle of 24 ° helix angle of 10 °,12 °,14 ° and 16 ° is carried out under the two conditions of drilling and crosscutting.The optimal spiral angle of double helix cutting head under the condition.(5)Study the influence of the taper angle of the cutting head on the cutting performance,the cutting head of 24 °,30 ° and 36 ° under the optimal spiral angle parameter developed in Step 4 Cut and drill into two kinds of conditions for numerical simulation study,get the best head cone angle parameters.Combined with the above simulation,the design of the optimal cone angle and the optimal spiral angle of cutting head of XTR260 cantilever boring machine is obtained.