Study On The Grinding Technology Of Helical-cone Drill

With the development and demand of mechanical manufacturing industry, there are higher and higher demands on hole processing. So drilling technology(drill, drill grinding and drilling process) has been taken as an important subject in the research field of machining.Conical twist drill is commonly used, while it has disadvantages that poor centering, large axial force and torque and the phenomenon of the tail’s raising of the conical drill will appear with improper parameters. So structure and materials of dill have been improved to meet the needs of production. Some new mathematical models of drill flanks are put forward. One of these is helical drill without the phenomenon of the tail’s raising. But the drill point grinded by this method is relative weak and has not enough strength. As far as the present situation, this paper proposed the research of grinding technical of helical-cone drill based on the grinding methods of conical twist drill and helical drill.This paper focused on the following aspects of exposition and research:(1) Development overview of dill was introduced and improvements on structure and material of current dill were made a summary. The research history about mathematical model of dill flank was reviewed. Also the current method on grinding helical drill, And put forward to the necessity and feasibility of researching on helical-cone dill grinding technology.(2) This paper gives the helical-cone drill grinding theory on the basis of the features of the grinding methods of conical twist drill and helical drill and set up flank, s mathematical models, then the simulation graphics of models using MATLAB was drew.(3) According to mathematical model, relationship between drill point geometry parameters and grinding parameters was analyzed. Solving equation of geometry parameters was established, and reference for study on the trend of geometry parameters with grinding parameters changed was provided.(4) The affect of grinding parameters on the structural parameters using numerical analytical method was got, and the curve diagram using MAPLE was drew. Sensitivity of grinding parameters under the curve was analyzed. According to the sensitivity, the reasonable and controllable parameters were selected which provided scientific guidance for grinding tests.(5) In Metal Cutting, cutting process is of great significance. Cutting force, cutting temperature and tool wear are the major indicators reflecting the cutting process, especially the cutting force. Drill is the most common tooling in drilling machining in this paper,the3D models of conical twist drill and helical drill are inputted into the finite element software DEFORM to set up drills drilling a simulation model.FEM simulation of twist drilling is carried out to identify the characteristics and to analyze the drilling quality of these two classes of drilling, including temperature distribution, drilling torque, drilling force, stress and elastic deformation of drilling tools. At last the paper makes comparisons about the simulation result between helical-cone drill and conical drill.From that,we can draw a conclusion that the cutting properties of the helical-cone drill is better than conical drill.It is clear that:the mathematical model proved correct accord tothe simulation graphics of models using MATLAB. Helical-cone drill point has an "S" contour and reasonable drill point geometry parameters. Under the same conditions, the result proce the machinability of helical-cone drill is better than cone drill.