套铣铣鞋结构设计优化方法

Optimization Method of Structure Design for Milling Shoes

现有套铣技术中套铣鞋结构设计对如何影响套铣作业,提高套铣效率考虑较少。文章根据流体力学和套铣鞋结构特点,在考虑固液界面拖曳力的基础上,建立了套铣管柱所受水力以及套铣鞋切削效率的计算数学模型,研究了切削齿数量和导流槽圆心角对套铣管柱所受水力及套铣鞋切削效率的影响,并给出了实例计算。研究表明:随切削齿数量和导流槽圆心角的增加,长城齿和波浪齿套铣管柱所受水力变化不同;导流槽圆心角一定,当切削齿数量小于等于6时,长城齿套铣管柱所受水力较小,受托压影响亦小,但此时长城齿套铣鞋切削效率小于波浪齿,当切削齿数量大于6时反之。建议在套铣作业时,合理选择套铣鞋结构设计,缓解管柱托压现象的同时提高作业效率。

It is rarely considered that how dose the structure design of washover shoes affect the washover operation in the existing milling technology.According to the fluid dynamics and the structural characteristics of the washover shoes,a mathematical model for calculating the hydraulic force of the washover string and the cutting efficiency of the wash-over shoes were established by considering the drag force of the solid-liquid interface.The influence of the number of cutting teeth of the wash-over shoes and the central angle of the diversion trench on the hydraulic force and the cutting efficiency of the wash-over shoes were studied,and an example calculation was given.The results show that the hydraulic force changes of the washover string of Great Wall cutters and wave cutters are different with the increase of the number of cutters and the central angle of the diversion trench.With a constant central angle of the diversion trench,when the number of cutters is less than or equal to 6,the hydraulic force of the washover string of Great Wall cutters is small,the influence of the torque and drag forces is small,but at this time,the cutting efficiency of the Great Wall cutters washover shoe is less than the wave cutters,and vice versa when the number of cutters is greater than 6.It is recommended to choose the structure design of the shoe reasonably in washover operation,so as to alleviate the torque and drag forces problems and improve the operation efficiency.