The invention discloses a segmented type boring bar with a guide support part and special for
machining a deep and long hole and an inner groove. The boring bar comprises the guide support part, a
tool bit part, a feeding and retracting mechanism, a rod body part and a hydraulic drive part. The guide support part comprises a guide head and an auxiliary support part. The guide head is divided into a front guide head body and a rear guide head body which are connected through a screw. The rear guide head body is connected with the front end of a sleeve through a pin, a
hydraulic cylinder is connected with the rear end of the sleeve through a pin, and a cutter bar is connected with the bottom of the
hydraulic cylinder through a pin. When the inner groove is bored, the guide support part has a supporting effect, and the local static rigidity of the
tool bit part can be improved. By means of the feeding and retracting mechanism, the axial positioning and the feeding and retracting movement of the tool can be achieved. The segmented type special tool with the guide support part is suitable for
machining the multi-layer inner groove and can also be used for boring the inner wall of the deep and long hole; a blade is symmetrically arranged, so radial force and
tangential force counteract, the rigidity of the cutter bar is greatly improved, and
machining conditions are remarkably improved.