| In this thesis, working principle of the BTA drilling and characteristic of drilling process are analyzed. With problems of chip breaking and chip removal disorder, the chip separation, chip breaking and guide bar of inner chip removal deep hold drilling are discussed in detail, In order to guarantee chip removal, the fluidity of chip liquid was analyzed and chose. Reasonable selection of location and shape of guide bar are analyzed and designed in detail.Buckling behavior of deep-hole machining arbor is analyzed, with static equilibrium method, buckling differential equations of weightless arbor restricted by machining surface under the action of combined compression and torsion, uniform helix is proved to be the exact solution of the equations. Through energy-variational principle, euler equation and according natural boundary condition are acquired. The acquired euler equation makes judging precision of approximate results possible.The main factor of influencing deep-hole machining precision are analyzed, the mechanism of hole center line deviation is discussed, mechanical model of arbor is established. By theoretical analysis, deviation of deep hole is acquired. Through comparison of deep-hole machining special machine experiment, consistency of measured values and calculated value of hole deviation is found, show that theoretical analysis is correct. With theoretical analysis and experimental verification of effect of supporting misalignment on hole deviation, a series of measures are proposed.By modal analysis of arbor with the finite element analysis software ANSYS, the finite element model is established, finite element grid is produced, and nonlinear of arbor in machining process is analyzed. Through comparison and analysis of finite element simulation results and experimental results, show that the effect of nonlinear contact of liquid, arbor and hole wall on arbor deviation is notable.
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