Faster cutting of aluminum stock

Saw News

Ken Massiah loading bar stock onto the input roller table of the KASTOtec AM4, which uses band speeds of up to 470 m/min.

'We achieve in excess of 430 cm 2/min cutting rate when sawing aluminium, allowing us to cut through a 400 mm diameter bar in under three minutes. That gives us up to double the productivity of our older saw'

Specialist aluminium bar, tube and plate stockholder, Metalfast, offers a 24-hour delivery service on most orders, but steady growth in business over the past few years was stretching its sawing capability, especially for larger diameter stock.

The solution was to install a German-built KASTO programmable bandsaw of 430 mm cutting capacity at the company's Highworth warehouse, near Swindon, to join an earlier model of similar capacity from the same supplier installed in the early 1990s. Called KASTOtec AM4, the latest automatic sawing machine is designed for high-performance cutting of aluminium using band speeds up to 470 m/min – more than two and a half times faster than equivalent general-purpose bandsaws.

Said Ken Massiah, machine operator at the Highworth site, "We achieve in excess of 430 cm 2/min cutting rate when sawing aluminium, allowing us to cut through a 400 mm diameter bar in under three minutes. That gives us up to double the productivity of our older saw. However, in trials KASTO has cut at nearly twice that rate – 800 cm 2/min – so as time progresses we can raise our productivity further.

The AM4 has a one-piece construction, polymer concrete in the saw head to dampen vibrations, twin column guides, and linear slides on the ways to prevent stick-slip. Immediately when entering and exiting a cut, parameters are backed off to protect the teeth of the bimetal blade. When in cut, load sensors on the hydraulics detect when the blade is not engaging the full width of the material and increase the in-feed up to 130 per cent of the programmed speed.

If the grade of aluminium being cut has a silicon content greater than about eight per cent, a carbide-tipped bandsaw blade can be used to increase blade life during unmanned shifts. To avoid damage to the carbide tips during the return stroke, there is the patented facility on the KASTOtec to retract the bar slightly and displace the blade so that it travels back without touching the stock on either side. This has the additional advantage of protecting the surface finish on the sawn faces.

Noteworthy is the high level of sawing ‘knowledge’ built into the control, which together with the intuitive operator interface allows even inexperienced users to extract the best performance from the machine. Up to 98 orders may be entered comprising cut length, number of pieces and cross sectional shape of the material. Size of the material to be cut is detected automatically by laser as soon as it is clamped, and cutting parameters remain constant as only aluminium is processed on the AM4 at Highworth.

Operation is round-the-clock on weekdays plus some weekend working, according to demand. This goes for all sawing machines on site

including the two 430 mm capacity KASTOs, a KASTOfunctional U bandsaw installed at the same time as the AM4, an Italian-built FOM Sika 400 circular saw also supplied through KASTO in Southampton, and four plate saws. Further KASTO saws are in operation at Metalfast's Huntingdon and Oldbury warehouses.