With exploration moving into deeper waters, deserts and plateaus, operators and contractors will continue to face complex technical and financial challenges. After various advantages of slim-hole drilling, especially great reduce of cost, are well known, slim-hole drilling has become an important technology and been applied extensively. However, existing three-cone bits and PDC bits can not satisfy the requirements of slim-hole drilling owing to limited structure and short life. So, Southwest Petroleum University (SWPU) has developed a new slim-hole bit, named disc one-cone bit, which combines one-cone bit with disc bit. This new bit will have expansive application prospect in deep drilling, ultradeep drilling and slim-hole drilling because of its less torsion, higher bottom-hole coverage coefficient and longer bearing life. During the development of new disc one-cone bit, it is very important to ascertain the arrangement and the structural size of disc tooth reasonably according to its rock-breaking mechanism. Ilowever, the factors to affect hit rock-breaking efficiency are more and restrict each other. If laboratory evneriment is named mil in rrcrareh n kind of new hit it will berlong period, much cost and only under very simplified conditions. Therefore, computer simulation has important technical and economic value during studying the new bit. This paper discusses rock-breaking mechanism and kinematics simulation researches of disc one-cone bit emphatically.

盘式钻头是一种新型齿形三牙轮钻头，其齿面制成与牙轮母线垂直的圆环形连续齿圈，改变了牙齿与岩石的作用特点及其破岩机理。利用牙轮钻头几何模型及计算机仿真技术，建立了盘式钻头与井底岩石互作用仿真模型、盘式钻头齿形几何模型及盘式齿形离散模型等，编制了盘式钻头与岩石互作用仿真分析软件。由仿真计算得到了给定结构参数的盘式钻头与给定岩石互作用后的井底模式。通过单齿圈复合破岩实验，得到了盘式钻头实际钻井时的井底模式，它与采用计算机仿真软件的仿真结果很相近，验证了仿真模型的正确性，为盘式钻头设计提供了新方法。

在牙轮钻头与井底岩石互作用模型的基础之上，将钻头在井底作纵向往复运动的位移作为钻柱纵向振动的下端边界条件，在适当简化的条件下，利用弹性杆理论和单元法建立了钻柱在钻井过程中由于钻头与岩石互作用及钻柱的弹性变形而导致钻柱产生纵向振动的动力学模型在给定初始条件和边界条件的情况下，采用数值计算方法求解了钻柱纵振模型。为进一步弄清钻头、钻柱在钻井过程中的实际运动规律和动力学性能，改进钻头、钻柱的设计方法，预防钻头、钻柱早期失效奠定了基础。