Simulation Analysis Of Deep-hole Drilling Process With BTA Drill Based On DEFORM-3D

Hole machining accounts for over 30% of the total mechanical processing,in which deep hole of depth to diameter ratio L/D>5?10 is more than 1/3. The proportion of deep hole machining is larger especially in aviation, aerospace, oil, nuclear power and other industry areas,and the requiremnts of deep hole machining quality and efficicncy is higher and higher. Deep hole drill is one of the key factors to realize deep hole machining, whose perormance directly affects the quality and efficiency of deep hole machining. BTA drill is the most widely used in all deep hole drills and there are two main structure forms of single tooth drill and staggered tooth drill now. Among them, the staggered tooth drill is divided into v-type and vi-type. The latter has been popularly used in foreign, but the former is still mainly used in domestic and little research on it is adopted. The drilling process of two types of deep hole drills is analyzed in this study, which is of great practical significance to promote the design optimization and performsance improvement of deep hole drill in our country.Focused on BTA drill, 3D model and finite element analysis model are established respectively by using Pro/lE and DEFORM-3D softwarc in this thesis, basced on the analysis of structural parameters design of two kinds of deep hole drills of v-type and vi-type. The drilling process of two types of deep hole drills is simulated. The entering drilling process of them and chip formation process and deformation law are analyzed. The change rule of cutting force of two kinds of drill bits into drilling process and cutting temperature distribution are revealed.The contact stale between the rake face of each tooth and the bottom of chip is observed, and wear prediction of the rake face of each tooth is given. The entering drilling process, chip morphology and drilling force of two kinds of deep hole drills arc observed and analyed through BTA deep hole drilling experiment.The results show that wear process of each rake face of BTA drill is consistent with the blades into drilling order, and more advanced cutter tooth is easier to be worn. Appropriately giving the relative height of each tooth, can not only shorten entering drilling time of the drill,reduce the blades to be worn too rapidly, but also can improve the effect of axial ladder splitting chip, raise the chip removal ability. With the chip breaker width or circular radius decreasing or its height increasing, chip deformation increases and chip becomes short relatively. With the increasing of strength and hardness or the decreasing of thermal conductivity of workpiece material, the cutting resistance increases, and cutting temperature rises. What's more, the maximum cutting temperature is distributed near the cutting edge and chip bottom of tool-chip contact surface. Besides, The drilling force fluctuation range of v-type drill is large, and the drilling process vibration is obvious. That's good for chip breaking, and the chip morphology is good; While the drilling force fluctuation range of vi-type drill is small, and the drilling process vibration is relatively stable. That's not good for chip breaking, and there are long strip chips.