At the Newcastle-under-Lyme facility of special-metals stockholder Langley Alloys, two German-built bandsaws specified for cutting with tungsten carbide-tipped (TCT) blades have replaced four out of six machines from a different supplier that are effective only when bi-metal blades are used.

As the down-feed on both KastoTec saws from Milton Keynes-based Kasto Ltd (www.kasto.com) is three-times faster,
the overall cutting capacity has increased by one third, while the floor area occupied has decreased by a similar amount.

This is precisely what Langley Alloys needed; orders have increased sharply since the start of 2017, but there is no room on the site for more bandsaws to handle the higher throughput. As an added bonus, the space that has been freed up has allowed the stockholder to increase the range of materials and sizes that it holds to well over 1,000 ‘line items’.

For example: Alloy 254SMO stainless steel is now stocked in larger quantities; Alloy 2205 duplex stainless steel has been added; and the variety of nickel alloys has been expanded from Alloys 625 and 718 to include Alloys 725, 825 and K-500.

The investment — approaching £2 million in stock alone — means that Langley Alloys has extended both the range and depth of material available.

Business development director Rodney Rice said: “Our success is despite the fact that half of our business has historically been in the oil and gas sector, which has been depressed in recent years.

Offsetting that, we have seen significant growth from many of the other industries we supply, including defence, marine, pulp and paper, chemical processing and general engineering.

“A quick response to customer demand is crucial, and installation of the Kasto bandsaws means that we can stock a broader range of materials and cut them quickly for supply in short lead times.”

Benefits of TCTOperations director Richard Bulmer added: “Cutting with TCT blades was key to making this a reality. We tried using them on our older bandsaws, but they were not rigid enough to cope.

The band would squeal through the guides, and excessive vibration wore the teeth out quickly. We were only able to cut 2m² of nickel alloy with a carbide blade, which was about the same as with a bi-metal blade — but at three-times the consumable cost.

“We are not quite there yet, but we will soon be getting 5-6m² cutting area per TCT blade on the KastoTecs, so cost per cut will be equivalent to bi-metal in terms of the consumable cost alone.

Taking into account lower labour costs due to operating four rather than six bandsaws five days a week, and sometimes on Saturdays — plus more capacity for ‘lights out’ running — the new machines will pay for themselves quickly.”

He added that when it came to purchasing the ‘carbide-enabled’ bandsaws, there was a preconception within Langley Alloys that Kasto was the way to go, as this make of saw is used widely in the stockholding sector.

As the machines were needed quickly, a decision was taken to purchase the two 430mm-capacity KastoTec AC4 models on display in the supplier’s Milton Keynes showroom.

One was fitted with Kasto’s carbide pack, including uprated motors to allow steplessly variable band speeds up to 50m/min, which compares favourably with typical bi-metal blade speeds of a little above 20m/min.

The other saw was a Kasto Performance Cutting (KPC) model; designed and built specifically for cutting using TCT blades, this features Kasto’s patented Trum guides that minimise band vibration on the side opposite the point of cutting.

Initially, Mr Bulmer took some Ferralium super-duplex stainless-steel bar to Milton Keynes for cutting trials, as this material forms a large percentage of Langley Alloys’ throughput.

Following successful tests, Kasto received an order for a four-week trial installation of the first bandsaw in Newcastle-under-Lyme, so that further side-by-side cutting comparisons could be made with the ‘conventional’ saws on site.

These proved that the KastoTecs were ideal for processing ‘difficult alloys’, including high-strength nickel types that are slow to cut using a bi-metal blade. Both machines were duly installed on a permanent basis.

Since their installation, further cost savings have accrued from reduced material wastage; and whereas the older saws are set to cut to -0, +2mm to ensure that material length is not undersize, the Kasto machines can be set to -0, +0.5 mm with confidence — although in practice they cut to within 0.1mm.

Over a large batch, and especially when processing costly alloys, the saving is significant.

Another feature of the bandsaws highlighted by Langley Alloys is a function within the Kasto control that allows a new TCT blade to be programmed to run in automatically at different reduced speeds to suit the tooth pitch.