The drill’s patented point thinning, special gashing and a 143° point angle provide excellent self-centering capabilities and reduce thrust, keeping the drill running straight, even at the highest feed rates. In addition, four margin lands deliver maximum stability when drilling cross holes and inclined exits.
A patented corner radius improves tool life significantly and provides excellent hole quality, meeting a hole tolerance range of IT9 to IT10, while effectively eliminating the workpiece chipping when exiting the hole.
“The drill’s low-thrust point design gives users the option to apply the drill under less-than-ideal clamping conditions, or on thin walled applications, or simply when spindle power is the limiting factor,“ says Frank Martin, product manager, Kennametal.
Extensive testing has shown that this new drill is a solution provider for those types of challenges, as well as for high volume cast iron production.
The drill’s proprietary AlTiN/AlTiSiN multilayer coating withstands the extreme abrasion and high thermal loads encountered when drilling grey cast iron, ductile iron, CGI, ADI, and GGG. The new coating is also resistant against the inclusions and pores commonly encountered in these challenging materials.
Ultra-high polished flutes and wide flute cross section promote efficient chip evacuation and further reduce heat and resulting thermal shock.
The new HPR drill comes with through-coolant as standard and with a DIN 6535 and 69090-03 MQL (minimum quantity lubrication) interface. With these features the drill excels in either wet or dry machining conditions.
“Whether drilling large quantities of holes or overcoming typical challenges in any type of cast iron workpiece, the HPR drill is clearly the solution,” says Martin.