PROBLEM TO BE SOLVED: To provide a BTA deep hole processor which can realize a sufficient sealing effect of a sealing part even when the fastening force with a fastener is small.SOLUTION: A BTA deep hole processor comprises a tool, a tool rotation mechanism that rotates the tool around the axial line, a spindle stock that supports the tool rotation mechanism, a spindle stock movement mechanism that moves the spindle stock in the axial direction of the tool, a cutting liquid supply device that supplies a cutting liquid between a cutting face of a workpiece and the tool, a sealing part brought in contact with the other side of the workpiece, a sealing part movement mechanism that moves the sealing part in the axial direction of the tool, a pressing force evaluation means that evaluates pressing force given to the workpiece from one side to the other side during workpiece processing, and a control means that controls the sealing part movement mechanism on the basis of evaluation results of the pressing force evaluation means. The control means is configured to control to press the workpiece from the other side to one side under such a force as to maintain a static state of the workpiece.SELECTED DRAWING: Figure 1
展开▼
