WNT’s range of WTX solid carbide drills has been developed further with the introduction of drills up to 50 x diameter for drilling steel and cast iron, and 30 x diameter for aluminium components. With the correct setup it is possible to drill to these depths without the need for a pecking cycle, making the WTX drills even more productive.
For steel and cast iron components the choice is the WTX Deep Hole Drill Type UNI, while the WTX Deep Hole Drill Type ALU is the choice for aluminium components. Both drills share common features, such as the 135 degree point angle and straight cutting edge that helps to reduce cutting forces. A key feature is the use of four guide lands (six on the ALU drills) that help the drill to maintain alignment and accuracy to h7. For improved swarf clearance and performance the drills also feature polished flutes and through tool coolant. Differentiating the two types of drill are the coatings used. For Type UNI drills a TiAlN multi-layer coating is applied, while for the Type ALU a special DLC (Diamond Like Carbon) coating is used.
These new drills will provide a real alternative to gundrilling as customer test reports are proving. For example in the drilling of a crankshaft in 42CrMoS4 chrome molybdenum steel the customer was drilling 12 holes per shaft using a 5.00mm diameter gundrill. The cutting data was 78m/min at 0.03mm/rev feedrate (144mm/min). By switching to the WNT WTX Type UNI drill the surface speed was increased to 81 m/min, feed upped to 0.1 mm/rev (500mm/min). This gave a cycle time saving of 26 seconds per hole or 5.25 minutes per crankshaft. Not only that, but tool life virtually doubled from 50 crankshafts/drill to 97.
The WNT WTX Deep Hole Drill range covers diameters from 2.00 mm through to 12.00mm in a variety of increments for diameter to length ratios of 16x, 20x, 25x, and 30x and between 3.00mm and 9.00mm for 40x diameter, with 50 x diameter restricted to sizes between 3.00mm and 6.80mm. Use of the drills is straightforward, with the only requirements for efficient use being the drilling of a pilot hole to 3x drill diameter and an initial reduction in speed and feed when entering the pilot hole and a reduction in speed just as the drill is retracted from the finish drilled hole.
“These new extensions to the WTX solid carbide drill range are delivering significant cycle time reductions for those companies making use of them. They bring the world of deep hole drilling within reach of any machine shop, and without the need for any specialist equipment or skills,” says Tony Pennington, Managing Director, WNT (UK).