A new twist on set-up time

The KM system from Kennametal has been a top performer in this area for over three decades, and is known throughout the industry for its high clamping strength and consistent accuracy in both spindle mounted and static tooling applications. The bending moment of KM4X is claimed to be substantially higher than any tooling interface available on the market today, superior even to Kennametal´s own KM design.

So when aerospace giant Boeing came to Kennametal with a request for a heavy-duty spindle connection capable of outperforming traditional CAT and BT-style adapters, tooling engineers turned to this robust and well-established platform as a starting point. The result was a 100mm spindle connection with four ball tracks instead of two and up to 40% greater clamping force than comparably-sized KM tooling.

That was 15 years ago. KM continues to thrive, and was adopted in 2008 by the International Organisation for Standardisation (ISO) as ISO standard 26622. The original Boeing inspired design has been renamed as well, and marketed for the past several years as KM4X100, a spindle platform popular with machine builders such as Fives Group, Mitsui Seiki, Stama, and others, as well as those machine shops looking for high rigidity in demanding machining conditions.

According to Kennametal, that popularity is about to grow. The company has announced the KM4X tooling family has gained a 63mm sibling, one aimed at a broader machine tool platform and therefore greater availability to the machining community.

“Just as we did with Boeing, we challenged ourselves to make a great solution even better,” says Bill Redman, Kennametal global product manager, tooling systems. “The clamping strength, bending stiffness, and RPM capabilities of the KM4X63 are dramatically higher than virtually any other connection out there.”

Mr Redman and others on the product management and engineering team recently approached a number of machine builders to ask for opinions on the initial KM4X product offering. Based on that feedback, Kennametal continues to expand the portfolio. The KM4X line-up now includes shrink fit toolholders, HydroForce hydraulic chucks, TG and ER collet chucks, and a variety of other spindle tooling, clamping units, and modular adapters, with more on the way.

By the end of 2016, we're going to add roughly 30 new line items, most of which will be extensions in the 80 to 200mm range, and centre line turning tools to support mill-turn applications,” says Mr Redman.

“We´ve found that, because of KM4X´s extreme rigidity, we can greatly increase gage lengths. This means our customers can reach much farther without having to buy a special tool, something that´s especially important with 5-axis machining; they can basically add on whatever extension length is needed and off they go, in both static or rotating applications. We're pretty excited about that.”

One example of this is a 674mm gage length KM4X boring bar displayed on an Integrex i-400 on the Mazak booth at this year´s IMTS. “KM4X63 has a maximum bending moment of 2,100Nm and, depending on the machine, clamping force of 36 to 58kN,” he says. “It´s the strongest connection available in this size range.”

It´s also faster. Mr Redman says KM4X63 comes ‘out of the box’ capable to 38,000rpm, which is higher than HSK-A and claimed to be dramatically faster than competing brands of spindle tooling.

For those workshops on the fence about spindle tooling and quick change, Mr Redman offers the following advice.

“There´s nothing worse than going into a shop that just bought a $500,000 machining centre or lathe and then discovers they should have opted for a different tooling platform,” he affirms.

“We as tooling providers have an obligation to educate customers and get them thinking about what they´re trying to accomplish; whether they need high spindle speeds for an aluminium or die-mould application, or greater low-end torque for titanium and HRSA machining.

“The majority of tooling systems out there can accommodate one of these things, but not both. We feel KM4X provides a competitive advantage no matter what you´re cutting.”

KM and KM4X work on stationary applications as well, as in this centreline turning tool holder for multi-tasking machines and mill-turn lathes. Due to its inherently balanced design, KM4X63 achieves spindle speeds 30% greater than HSK, and nearly twice that of comparably sized polygon-style toolholders.

The anatomy of the KM4X clamping mechanism features four ball tracks instead of two. On the system size 63, this provides 50% greater clamping force over PSC, and 150% higher clamping force than HSK63.

KENNAMETAL www.kennametal.com