American Heller's BTA Oil Pressure Head is a Deep Hole Drilling Accessory whose 3 main purposes are to 1) introduce coolant to the tools cutting zone, 2) provide a sealing mechanism and 3) act as a tool guide.
Coolant Induction and Chip Removal
The BTA Oil Pressure Head directs the cutting oil under high pressure between the cutting tool and the workpiece bore. It forces the chips away from the machined surface and out through the hollow tool and boring bar or drill tube. This prevents the chips from scoring the machined bore. Since the coolant is finely filtered only clean coolant contacts the bored surface thus enhancing the bore quality.
A Sealing Mechanism
In order for pressurized coolant to be introduced to the cutting tool, there must be a containment seal between the Pressure Head and workpiece as well as the Pressure Head and the O.D. of the boring bar. The stuffing box creates a seal with the boring bar or drill tube O.D. The workpiece seal varies with style of BTA Oil Pressure Head in question.
A Tool Guide
As the drilling operation begins, the tool is guided by the boring bushing in the BTA Oil Pressure Head. This assures that the hole start is accurate in size and alignment. As soon as the tool leaves the bushing and enters the workpiece, it is kept aligned centrally by the outer cutter and carbide guide pads.