CARBIDE SEES SAWS BENEFIT benefits multiplied

More and more are exploiting carbide’s cutting capabilities. Martin Atkey casts an eye over some of the latest bandsaw developments and applications

awing is by far the most popular Just like any ,a bandsaw high-strength and heat-resistant alloys. Smethod of cutting up material into depends heavily on the performance of the While tungsten grit bands (where small blanks for subsequent .While cutting tool it uses.So it’s important to particles of tungsten carbide are bonded circular saws offer advantages in certain specify the most suitable band (in terms of to flexible alloy backing) can also be areas (see below),it is the bandsaw which type,pitch,set and geometry),select the effective on hard and metals, tends to dominate the bulk of such cutting- right feeds and speeds for a given tungsten carbide-based bands are initially off tasks.The widespread appeal of the material/section,use suitable cutting fluid still relatively expensive.However,the latest bandsaw (both straight and mitre cutting and ensure good swarf removal.As far as series of bi-metal bands,particularly high- versions) is down to its all-round band technology goes,there are several alloyed steel types,are also capable of performance,lower cost and ability to cut different styles to consider including: cutting at faster production rates. all material types and sizes.Modern standard carbon steel,bi-metal (and high- The combination of advanced CNC bandsaws will provide a quality finish on alloyed versions),TiN coated,tungsten machines and the latest bands can have most materials,precise cut-to-length carbide tipped (TCT),tungsten grit and quite dramatic results.For example,the accuracies and can usually handle bundle even diamond edged ones. launch of the Behringer HBM range of cutting tasks.Combined with various Recent advances in TCT bands have bandsaws,from Kaltenbach,marked a control and material feed options,such greatly improved performance,particularly notable increase in performance, machines offer good productivity when cutting difficult or abrasive metals particularly on hard and difficult metals. combined with low cost-per-cut rates. such as titanium,Inconel 78 and other With these new machines, time reductions

Circular saws – precisely

Suitable for cutting sections up to (HSS or TCT), which provides fast Another newcomer is the Missler around 150 mm diameter and handling operation. A full cutting cycle is 15 sec CS4 automatic high-production circular volume work, circular saws come into for 70 mm diameter bar. Cutting capacity sawing machine. Introduced at the EMO their own where surface finish, close is up to 100 mm diameter. exhibition in Milan, the saw can use HSS tolerances (down to ± 0.1 mm) and fast Latest high-volume machines from or TCT blades and cuts rounds up to 100 cycle times are key requirements. Using Kasto are the KASTOspeed C9 and M9. mm diameter. It has three-axis CNC (for TCT saw blades, modern machines can These high-speed circular saws only blade rotation, saw-head feed and bar rapidly process all types of metal and require a few keystrokes to enter the feed stroke), electronic vibration combine high levels of surface finish and data necessary to fulfill an order and the damping for quality cuts, advanced saw squareness with a low cost-per-cut. control contains knowledge of the blade guidance and a swarf conveyor. Kaltenbach’s new KMR 100AP optimum cutting parameters for common While bandsaws are popular for straight cutting circular saw is designed materials. There are two versions of the bundle cutting tasks, small batch sizes for the high-volume cutting of ferrous saw – the C9 (which uses TCT blades) for and frequent changeovers can degrade and non-ferrous metals. Instead of an cutting high-alloy steels up to 1400 production efficiency. Against this upstroking blade action, the saw uses a N/mm2 tensile strength and the M9 backdrop, RSA has developed its CNC pusher approach, where the (which can use HSS or TCT blades) for Rasacut circular sawing system with material is fed against the rotating blade non-ferrous metals. significant emphasis on reduced tooling

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of 60 per cent and more are being three times more expensive than bi-metal and large gullet tooth geometry are achieved when cutting some of the most types.Nevertheless,there is still an overall combined with precision heat treatment exotic materials.Difficult metals such as reduction in the cost of the consumable,as and finely controlled peening on this M42 tool steel,for example,can typically take 70 carbide bands can cut four to five times bi-metal band in order to provide min and more for a single cut,depending more material.For example,Hytemp has maximum productivity and cost-effective on material size.However,HBM bandsaws typically halved its cost-per-cut. cutting. can reduce this to less than 30 min.Such Not to be outdone,bi-metal bands In one application,the Gladiator performance is down to a combination of have also upped their performance of late. bandsaw band substantially reduced costs improvements in sawing geometry, One example of this is the Gladiator high- for the process plant and equipment machine structure,cutting control systems performance band from L S Starrett which manufacturer Fairport Process Equipment. and advances in band technology,notably has been designed for improved cutting on Following successful trials,the new band TCT. a range of work materials – including high- has improved cutting performance on steel Nickel alloy stockist Hytemp strength steels,stainless steels,tool steels sections,flat plate and bar up to 200 mm Engineering started changing from and tough aerospace alloys.Positive rake diameter at the company’s steel fabrication conventional bi-metal bandsawing to TCT blades in March 2003 when the company installed its third automatic bandsaw,a KASTOtec AC4 from Rivers Machinery. Within eight months,TCT blades were performing half of the sawing at the Sheffield works,routinely cutting at speeds up to two-and-a-half times those attainable with bi-metal bands.Offsetting the speed advantage of carbide cutting is the higher cost of a such bands,which is typically

Gladiator M42 bi-metal bands can handle tough aerospace alloys

times (changeovers take about 5 min) and the automatic separation from the tube bundle. With a cutting accuracy of ± 0.2 mm, the saw’s output can be several times higher than a bundle-cut, bandsaw-type system. Finally, the new Adige TS72 circular saw, from BLM-Adige (UK), combines the benefits of greater productivity and accuracy with ease of use. With this saw, virtually all the operator has to do is to program the tube diameter, wall thickness and cut length after which the CNC will then set itself for optimum cutting. The saw will handle round tube from 8 to 102 mm diameter and solid bar up to 40 mm diameter.

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shop in Stockport.As production manager Dave Thomson explained:“The introduction of the Gladiator band has given us greater cutting performance on both steel and and it lasts longer and provides faster,straighter cuts.” Motor power is also important on bandsaws (especially to drive TCT bands) and one solution is to drive both bandwheels instead of just the one,as this ‘pushes’and ‘pulls’the band from both ends of the machine.The latest series of Missler bandsaws,from Saws (UK),uses such a system and this can double the power to be transmitted to drive the bandsaw blade. In addition,Amada’s brand new automatic horizontal bandsaw, the HFA700 CII,has also been designed for use with TCT bands and features a powerful 15 hp motor and a swarf conveyor.This machine is due to be launched in the UK by Birkett Cutmaster later on this year. Meanwhile,the new KASTOtec AC7 bandsaw has been designed for cutting rounds up to 730 mm diameter or sections up to 800 by 730 mm.This 18 kW machine uses TCT bands although a version (the The KASTOtec AC4 carbide bandsaw in action at Hytemp Nickel Alloys A7) is also available which uses bi-metal ones.The saw head contains polymer strength and corrosion-resistant bearing Centre in Bolton,along with various other concrete to dampen vibrations and reduce properties are essential. straight cutting and automatic Behringer noise,and has twin column guides with “Beryllium copper alloy is a relatively bandsaws supplied by Kaltenbach. linear slides on the ways to prevent stick- high-value material,”says Stewart Emslie, Stocking an extensive mix of aerospace slip.A novel feature is incorporated where, NGK Berylco’s general manager.“The metals,comprising alloy steels (including at the end of a cut,the bar retracts slightly Amada 400W bandsaw’s ability to reduce stainless) and aluminium alloys,Corus and the band displaces in the opposite waste material to minimal levels,while provides a total cut-to-length material direction to avoid damaging the carbide providing fast accurate cutting to fine service. tips during band return (or the surface tolerances was a prime consideration in its The Behringer HBP430PCM sawing finish of sawn faces).Material feed is selection for our Salford stock-holding cell has a cutting capacity up to 430 mm managed by NC to ensure accuracy of cut centre.The saw is operator-friendly and, diameter and features an integrated input and up to 98 orders may be entered in the being fully automatic,it is easily pre-set to magazine and automated material traverse control. produce batch quantities of cut-to-length and feed.Stock is automatically fed into Another virtue of the bandsaw in products at the push of a button.The the saw’s jaws by motorised rollers,while general is its narrow kerf – important if you machine stops automatically when the hydraulic output gripper and are cutting expensive alloys.One example reaching the required output,leaving our component sorting system enable of this is illustrated by an Amada HA400W operator completely free to attend to other automatic pick-and-place of finished or horizontal bandsaw which has allowed duties.” recyclable/scrap material.Multiple NGK Berylco UK to cut costly precipitation- While only accounting for a small programs can be loaded to allow for hardened beryllium copper alloy with high percentage of installations,unmanned overnight,unmanned operation and the precision (down to 0.1 mm) and low sawing cells are a growing attraction for machine’s CNC system is a user-friendly, material waste.The company supplies some manufacturers with particularly high- Windows-based touch screen system.The batch-cut beryllium alloy bar,plate and volume cutting-off demands.One such cell complete Behringer cell is supplied with hollow sections primarily to the oil-related has been installed at the Corus safety light barriers and fences to conform and aircraft industries,where high-fatigue Engineering Steels Aerospace Service to EU regulations. M

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