Design And Research On Hydraulic Roofbolter

Roofbolter is one of the key equipments for the construction of bolt support, which influences support quality and support speed. The monomer roofbolter by rotary cutting breaking rock, has become the main trend of the production and development of drilling machines for bolt support Heavy machine body and low reliability is one of the main common factors restricting them further spreading use. It is urgently necessary to develop a kind of roofbolter with high performance. According to the existing problem, hydraulic roofbolter is designed and researched in this dissertation.Firstly, the breaking rock mechanism of roofbolter is studied. This dissertation systematically analyses the breaking rock characteristics, the physical and mechanical property of rock while rotary cutting, and some factors influencing drilling rate and effectiveness of rotary cutting breaking rock.This paper puts forward applying non-circular planetary gear hydraulic motor to roofbolter, and analyzes the structures and performances of different types of non-circular planetary gear motors. On the basis of studying on the non-circular planetary gear mechanism and movement, the design formula and constraint condition of pitch curve is theoretically derived. There are many objective functions and design variables to optimally design a non-circular planetary gear motor, the design variables are discrete, some parameters are interdependent and the influence relation among them can not be seen clearly, so the robust optimization design method based on orthogonal test is adopted to design a non-circular planetary gear motor. The mathematical model of robust optimization design for a non-circular planetary gear motor is established. Quality characteristic datum of various design schemes are obtained by computing. By means of signal-to-noise ratio, combination of motor structure parameters to meet design requirements is gained. All these ensure the motor to have a strong robustness under a more loose process condition. Based on robust optimization design for the motor, product design of the non-circular planetary gear motor and the new hydraulic roofbolter is carried out, trial production is performed by a manufacturer.While rotary cutting rock, the slender drilling tool for roofbolter bears rather complicated working conditions and outside force. It has complicated deformation, kinematics and dynamics status. This paper analyzes and researches the statics and dynamics characteristics of drilling tool using finite element analysis simulation software ANSYS more accurately and reliably, which mainly includes foundation of finite element model for drilling tool, determination of boundary conditions, setting of restrictions and load, analysis of force-bearing and deformation characteristics, modal analysis including torsional vibration, longitudinal vibration and transverse vibration. The research results can provide important reference for scientifically designing drilling tool and roofbolter, reasonably determining drilling parameters and directing practical production.The mathematical model of static and dynamic characteristic of the hydraulic roofbolter is established on the basis of reasonable hypothesis. After studying, the velocity characteristic equation of rated load starting, the load characteristic equation of normal work and the dynamic characteristic equations which are the response of speed output to input of step flow and the response of speed output to input of step load are obtained. By experiment, parameter values in the mathematical model and test curves related to the characteristic of hydraulic roofbolter are gained. The simulation is carried out with MATLAB and the simulation curves are in good consistency with test curves. The results show that physical model, mathematical model and simulation model of roofbolter's characteristic are reasonable. It verifies the accuracy of theoretical analysis research. Underground practical drilling test has indicated that the roofbolter possesses the features of reasonable design, compact structure, light weight, fast drilling rate, easy operation and high reliability, which can completely meet the demands of application.