Blade flexibility and high productivity

Specialist stockholder serving the oil and gas industry, Howat Group, perhaps better known by its trading names AMS, ESS and Ancon, has installed a 14^th Kasto bandsaw – a KASTOwin pro AC 5.6 – at its new centre in Barnsley, which opened at the end of 2018.

Half of the sum went on acquiring a freehold, 60,000m² property on Cortonwood Drive in the Dearne Valley area of the city. The remainder was spent on infrastructure, materials handling equipment, two further Kasto bandsaws and refurbishment of all the older models, some of which have been in service since the 1990s and still cut accurately.

The German-built KASTOwin pro, supplied ex-stock from the manufacturer's UK subsidiary in Milton Keynes, is a competitively priced machine designed for cutting tough nickel, titanium and stainless steel alloys up to 560mm in diameter using a tungsten carbide-tipped (TCT) blade. However, the machine also allows economical cutting of low alloy steels when the blade is swapped for a high speed steel (HSS) bi-metal type.

Howat's operations director Emma Parkinson comments: "We have four dedicated carbide cutting bandsaws onsite which include KASTOtec AC5s and now the KASTOwin pro, which is even more capable. They are ideal for cutting our Inconel 625, 718, 725, 825, 925 and K500 stock.

"The latest investment was to increase our overall cutting capacity but also to improve efficiencies around nickel alloy cutting specifically. The remainder of our sawing plant with capacities up to 800mm diameter are intended for bi-metal cutting, but can also use TCT blades with offset teeth.

"The advantage of the latest KASTOwin pro saw, apart from its ability to use either type of blade economically, is its high productivity, which is down to fast cutting speeds and quick set-up using the new touchscreen control."

Programming is fast with the Kasto EasyControl, as cutting parameters for any given material, size and cross section are determined automatically by a built-in database, so all that is needed is to enter the cut length and number of pieces required and press start.

The productivity benefit is most pronounced when cutting nickel alloys. Formerly, the company was sawing Inconel 718 with a TCT blade at 3 to 4 cm² per minute, but on the KASTOwin pro that has risen to an average of 12 cm² per minute. So for example a 200mm diameter bar that would previously have taken up to an hour and a half to cut can now be processed in less than half an hour.

Ms Parkinson explained that she was familiar with the benefits of the latest German-built bandsaws compared with the performance of the legacy machines, having worked with this make of saw when previously employed at another stockholding company nearby.

So when Howat Group, one of the largest stockholders in the UK, needed more capacity to cope with an increasing number of high volume orders both for nickel alloy billet and for low alloy steels, the KASTOwin pro was a logical choice. The large batch sizes frequently ordered make it economical to spend time changing from an expensive TCT blade to bi-metal to extend the life of the tungsten carbide tipped teeth.

A feature of the automatic KASTOwin pro is its innovative, electro-mechanical downfeed via by two ballscrews, each with a servo drive for precise, infinitely variable control. The positive motion allows smaller tolerances to be set, typically -0/+ 0.5mm for most stock, minimising material wastage. There is a retraction unit for separating the blade from the material to protect the cut surface when the saw head moves back, which also helps to minimise tool wear.

The band is driven by an 11kW motor, delivering infinitely adjustable cutting speeds from 12 to 150m/minute and providing plenty of capacity for TCT sawing. Helping to dampen vibration and lower noise during operation are ‘Trum’ guides mounted at the return side of the blade, inside the top of the saw head guarding. They suppress vibration on the side opposite from the cutting action, prolonging blade life and promoting high squareness accuracy and good surface finish.

Partly due to the larger orders being received and also because of the high value of nickel-based metals, the monthly turnover of Howat Group trebled within a few months of the stockholder opening its new facility. Key to maintaining growth is providing customers with a high quality service in terms of prompt delivery of material that is within tolerance.

Ms Parkinson concludes: "It is for this reason that we have more or less standardised on Kasto sawing equipment and see the supplier as a partner to our business. We regard the manufacturer as a premium brand whose rigid and technologically advanced bandsaws maximise blade life and cut accurately for decades, despite heavy use."

Kasto www.kasto.com