Shield Machine Disc Cutter Vertical Vibration Characteristics

Presently, China has already become the world's biggest shield machine market. And the demand of the shield machine still very exuberant. With the development of Urban Mass Transit, the potential market value of the shield machine will reach 20 billion yuan, experts predict. As one of the main cutters of shield machine in the cutter head, disc cutter has the advantages of larger and faster rock-fragmentation during operating process. Its performance directly affects the excavation efficiency of shield machine, while the cutter's vertical vibration impacts the rock breaking efficiency as well as the cutter life. The research on the vibration characteristics analysis for disc cutter acts an important role in the cutter's structure design and the cutter head axially propulsion systems dynamics model. The paper comes from the topic "cutting mechanism of rock and theory of cutterhead design", which is the sub-project of the National Key Basic Research and Development Program of China (973 Program).The paper complete contents as below:1) Based on the former two degree of freedom vertical vibration model research, the mechanical model of disc cutter has been analysis. The cutter is divided into three parts, which is more reasonable for node splitting, qualitative investigation and calculation of rigidity and damping. The three degree of freedom vertical vibration model has been built. It can reflect the actual condition of cutter vertical vibration.2) The cutter vertical vibration has been simulated using mathematics software MATLAB. Herrenknecht disc cutter and self-made experiment cutter are studied as examples. Take the step force and sine-wave force as input conditions, the vibration model is simulated. The vibration characteristic has been analysis.3) On the basis of available mechanical vibration system natural frequency measurement experiment, the new testing table disc cutter natural frequency measurement experiment is been researched. According to the frequency characteristic curves, the cutter's natural frequency is obtained. And the related theory was verified.4) Using the circle cutting test table, the cutter vertical vibration measurement system has been designed. The measurement issue has been solved successfully. Throughout the experiment, the vibration curves during the cutter cutting process were obtained.