The FS designation denotes the tool’s ‘full solid’ carbide tip, which looks like the tip of a solid carbide drill. That means the carbide tip fully covers and protects the steel holder from ‘washing out’, but it not only looks like a solid carbide drill, it also works like one, Kennametal says.
KenTIP FS has a radically new design, one that incorporates a number of important features that separate it from the ‘me too’ modular drilling crowd, they are:
Critically, KenTIP FS has a patented taper interface that provides maximum rigidity and accuracy. Its retention lock eliminates pullout and its large bearing surface is able to withstand extreme torsional loads, without pocket deformation. And since the full solid carbide insert has no mounting screw, there’s no risk of damage to the clamping mechanism from chip or workpiece contact.
Highly polished flutes that improve chip evacuation and reduces wash out near the tip.
Instead of the two coolant holes found in most modular drill designs, KenTIP FS has four -two at the tip and two in the chip gullet directly behind the head. This ‘multicoolant’ approach provides greater coolant volume to prevent chip packing while simultaneously drawing heat away from the cutting zone, prolonging tool life and improving hole quality. It also allows the company to tailor the cutting fluid needs to the application.
For example, adhesion and flank wear are a big concern in stainless steels and cast irons. Inserts with HPL and HPC point styles have through-the-tool coolant channels to provide better lubrication in this area to overcome the issue. In steel, though, it’s better to concentrate coolant to the rake and take the heat from the contact zone between chip and rake surface. So front coolant holes are eliminated in the HPG geometry inserts, so as to raise insert tool life and improve chip breakage. In addition, this avoids built-up edge and makes the insert more rigid, which allows higher penetration rates in steel applications.”
The HPG geometry is also available in a new, highly wear-resistant carbide grade, KCP15A, designed especially for steel. Its newly-designed point angle and self-piloting chisel edge offer better positioning accuracy and hole straightness than other drills in this class, even under high feed rates, it is claimed. The insert corners are protected with small chamfers to reduce chipping, and the margins are similarly reinforced, making the HPG geometry suitable for the cross-holes and inclined exits encountered in hydraulics manifolds, for example, or the stacked plates used in heat exchanger production.
HPL geometry sees a split point designed to reduce cutting forces and break up long-chipping aerospace and medical alloys. It too is available in a new grade, in this case KCMS15, a wear-resistant, fine-grain carbide with an anti-adhesive AlTiN coating that extends tool life.
And for cast, ductile, and compacted graphite irons, the HPC geometry offers four margin lands and a radiused point that eliminates the exit chipping and cracking common with these materials, with a specially-designed chip gash that clears chips quickly in combination with the front coolant exits.
All three insert styles have 143°points and specially prepared, polished or honed edges for maximum tool life.
Says Alexander Schmitt, senior global product manager for modular drilling at Kennametal: “Between the HPG, HPC, and HPL geometries, the KenTIP FS can handle most anything a solid carbide drill can, but with far lower cost per part and equal or greater performance,” says Schmitt.
“The rigidity and stability of the KenTIP FS interface is crazy, and since the drill has a full solid carbide front, the interface can withstand more heat and abuse than competing modular drill technologies. In addition to that the carbide tip fully covers and protects the steel holder from washing out. We simply put carbide where it matters," says Schmitt. “Granted, there will always be extremes where nothing but a solid carbide drill will do, but for perhaps 90 percent of the applications we see, the new design works exceptionally well in a variety of materials. Kennametal put a lot of time and effort into optimizing KenTIP FS, and we look forward to offering it to our customers.”