Gun Drilling Systems
High pressure coolant is delivered through a duct inside the drill and forced through the center of the gun drill. The coolant provides lubrication and aids in chip removal. Chips exhaust through a V-shaped chip flute along the outside of the drill. Due to the v-groove, the cross section of the tube occupies 3/4 of its circumference.
Gun drills can be used on a variety of machining and turning centers equipped with sufficient high pressure coolant and filtration systems. These tools and this system allow depth to diameter ratios in excess of 100x's dia. BTA Heller offers several different carbide grades, coating and grind options.
BTA Heller sells gun drills in diameter ranges from 0.055" to 2.0.
Single Tube Drilling System
The STS Single Tube System or sometimes referred to as the BTA system: Coolant is supplied to the tool through a pressure head unit which seals and clamps against the part. The coolant is directed to the cutting face via the space between the drill tube and the hole being drilled. This Positive Coolant flow provides both drill head lubrication and proper flow for chip removal. The combination of chips and coolant returns internally through the I.D. of the tool and drill tube and then back to the coolant.
The STS / BTA system supports tools ranging from .437"- 30.000" diameter. These tools and this system allow depth to diameter ratios in excess of 100x's dia. In most cases the STS / BTA system is setup on dedicated deep hole drilling machines. This system is the best choice for extremely deep bores and for materials with poor chip forming properties such as stainless steel, Titanium, and low carbon steel.
BTA Heller offers a full line of brazed and indexable drill heads and all accessories for this system.
Double Tube Drilling System
The coolant is supplied at the spindle through a special coolant inducer or connector. Pressurized coolant flows through the annular space between the O.D. of the inner and the I.D. of the outer drill tube towards the drill head. Most of the coolant is forced through holes in the drill head providing lubrication and chip evacuation through the inner tube. The remainder of the coolant is diverted directly back through the inner tube via the venture slot. This creates a partial vacuum in the inner drill tube and forces the coolant and the chips through the chip exhaust port.
This system supports tools ranging from .787"-7.240" diameter. These tools and this system allow depth to diameter ratios in excess of 100x's dia. The DTS system can be used on conventional machine tools such as: lathes, horizontal boring mils, and machining centers which have suitable feed mechanisms, rigidity, and our self contained coolant system.
BTA Heller offers a full line of brazed and indexable drill heads and all accessories for this system.