Product Details Supplier Info More products

MAG Industrial Automation is to exhibit cryogenic machining at IMTS, demonstrating a development that utilises a through-spindle, through-tool cooling system for aggressive metal removal applications.

The US Navy-sponsored development efficiently cools the cutting edge, enabling higher cutting speeds for increased metal removal, longer tool life or a blend of the two advantages.

The liquid-nitrogen (-321F) cooling system can also be combined with MQL (minimum quantity lubrication) to reduce tool friction and adhesion, enabling even higher metal removal rates or longer tool life.

Ideal applications involve aggressive metal removal in hard workpiece materials such as titanium, nickel-based alloys, and modular or compacted-graphite iron (CGI).

Doug Watts, vice-president of engineering at MAG, said: ‘We are still in development, but have achieved 60 per cent speed increases in milling CGI carbide, and up to four times using polycrystalline diamond (PCD) tooling.

‘With the addition of MQL, we tripled speeds with carbide but showed no further benefit to the fourfold increase with PCD.

‘These facts focused on metal removal increases, while keeping tool life equal to what would be achieved with conventional coolants.

‘Early results indicate this technology could improve the lifecycle cost model for machining in a “hard-metal” environment by reducing the required number of machines and associated plant infrastructure, or possibly increasing tool life beyond anything thought possible today.

‘Cost-wise, cryogenic machining becomes even more competitive when you consider it is a non-issue environmentally.

‘There is no mist collection, filtration, wet chips, contaminated workpieces or disposal cost, and certainly less energy consumption without all the pumps, fans and drives that go into handling coolant,’ he added.

According to Watts, the key to the system’s efficiency is its ability to concentrate the cooling effect in the body of the cutting insert.

Watt claimed: ‘Cryogenic machining has never been done this efficiently before, with liquid nitrogen passed through the spindle and into the insert.

‘Through-tool cooling provides the most efficient heat transfer model, and consumes the least amount of liquid nitrogen.

‘Our development work to date has focused on milling and boring, where consumption has been about 0.04litre/min per cutting edge.

‘We believe drilling and tapping should be even less,’ he added.

Watts said that tests by MAG have shown the range of capabilities for diamond tooling can be expanded with cryogenic cooling, for example, extending the heat limit in CGI by three to four times.

Carbide cooling, which is more affected by abrasive wear, responds best when MQL is combined with cryo cooling.

The through-spindle cryogenic cooling system is suitable for motorised, belt-driven or geared spindles.

At IMTS, a through-spindle cryogenic delivery system will be demonstrated on a MAG vertical machining centre.

MAG Industrial Automation Systems

View full profile