难切削材料和深孔结构都具有重要的功能和较差的工艺性。在难切削材料上加工深孔，刀具容易走偏，其深孔精度是决定产品性能和寿命的关键因素之一。本项目研究深孔刀具液力自定心、自导向、自纠偏原理，为提高深孔加工精度提供理论支持。.项目借鉴滑动轴承动压润滑原理，以楔形油膜定位、引导、纠正深孔刀具；借鉴滑阀顺锥特性，在刀杆上设置顺锥以纠偏；借鉴陀螺原理，在刀杆上加工螺旋槽，使切削液旋转以稳定刀具。通过本研究掌握流场特征和系统的动力学特性，求得流体对刀具系统的作用力及抗干扰能力系数，获得油膜的刚度矩阵、阻尼矩阵及油膜使刀具系统多维颤振衰减的规律。以楔形、顺锥、螺旋槽结构参数、切削液参数与材料的切削力为变量，建立多变量优化设计的约束条件和计算原则。.所提出的原理以切削液实时自动定位、纠正、稳定刀具，与已存在200年且为各国采用的深孔加工原理有本质的差别，可促进深孔加工在线纠偏难题的解决。

Titanium alloys, super alloys and stainless steels are important materials. Besides, deep holes have important functions. But it is Difficult to make a hole in the material listed above because the cutting tool is easy to deform and deviate. As a result, the performance and life of many products are decided by the deep holes made. . A principle is put forward to make cutting tools located in deep hole centers, self guided, self-rectified with cutting fluids. When the cutting tools are used to drill titanium alloys, super alloys and stainless steels, they will still be in right places if this principle is applied..In this research, the deep hole cutting tools will be supported, located and rectified by wedge-shaped oil films during deep hole machining just as shafts are supported, located and rectified by oil films in hydrodynamic lubrication bearings. A positive cone is fixed with the drill. The rod connected with the drill is made with multiple spiral grooves to make the cutting fluids rotate round the the rod and keep the rod steady..After this research, the characteristics of the flow fields will be known, the forces and moments of the oil films acting on the cutting tools will be calculated, stiffness matrices and damping matrices of oil films will be discussed, the attenuation of vibration of the cutting tools will studied. Based on the forces, parameters of the oil films, cones and spiral grooves, constraint conditions and calculation rules of the optimization of the cutting tool system will be decided. .In conclusion, the novel principle is essentially different from the existing principle of deep hole machining, which has been existing for 200 years and has been widely used by countries all over the world. It can locate, guide, and rectify the cutting tools by simple structure along with existing cutting fluids, and will improve the straightness and the positional precision of deep holes.