P.P. Profiles has installed a colossal 39m long Kerf plasma and flame cutting machine to process almost 40% of its steel.

Like many small start-ups, P.P. Profiles Ltd. was a business conceived in a remarkably small building. In this case, the basement of a cotton mill in Walkden, Greater Manchester (UK).

Forty-three years later, the profile and processing company has just bought a plasma and flame cutting machine from Kerf Developments that, at 39m in length, wouldn’t fit into most factories, let alone the basement of a cotton mill...

The business generated immediate success that led to the formation of P.P. Profiles (West Yorkshire) Ltd. in 1978. The company moved twice over the years before settling into its current 70,000 square foot site in Batley (UK).

Over the last four decades, the subcontract manufacturer has built a reputation for providing cutting solutions for carbon steel, stainless steel and a range of additional materials in the nuclear; oil and gas; construction; rail; bulk handling; food; water & waste; storage tank and yellow goods industries.

The 40-employee business produces anything from one-offs to small and large batch runs that range from small components to extremely large ones. For a scale of the workload at the heavy engineering business,

it is processing an average of 400 to 500 tonnes of steel every month – almost 40% of this material is run through its new Kerf RUR4500 plasma and flame cutting machine.

It is this reliance on the machine that justified its acquisition. The level of investment at P.P. Profiles (West Yorkshire) Ltd now stands at more than £2m in the last two years.

An eye on efficiency

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The reason driving the investment in the colossal Kerf RUR4500 was the fact that two older 12m x 2.5m flame cutting machines and a 6m plasma machine, which were creating inefficient workflows.

Commenting upon the acquisition of the Kerf RUR4500 machine, P.P. Profiles (West Yorkshire) Ltd. commercial director, Daniel Morley, explained: “We specified the Kerf RUR4500 with a single high-definition 400-amp plasma cutting head on a 12m x 4m bed and a two-machine 24m x 4m bed that consists of both a six-head and a four-head flame cutting gantry – all in a single 39m x 4m cell. This allows us to load much larger jobs and has opened up new markets, as parts of over 12m in length are not uncommon.”

The arrival of the Kerf RUR4500 machine made the previous two flame and one plasma machine surplus to requirements, reducing the required floor area and drastically improving efficiency and workflow.

Referring to the savings, Daniel Morley added: “Anybody wishing to not only survive, but thrive, in the UK manufacturing sector must have efficiency at the forefront of their minds. Before the arrival of the Kerf RUR4500, we had to run a late shift and a night shift.

The Kerf machine cell instantly eradicated the need for extra shifts and we now only work a day shift. This is because each of the three previous machines required loading, material processing, unloading of steel sheets (which could be up to 12m long) and then cutting the sheet remnants into smaller-sized quantities for scrap disposal. This could be very labourintensive and took place while the machine was not cutting…. Our crane operator would be feeding three machines with material, instead of just one.

“Now, we have four people running the three machines within the Kerf RUR4500 cell. There are operators running each of the two flame cutting gantries and another operator on the plasma machine. A crane operator feeds the Kerf machine – he organises and sorts material flow, as well as ensuring that the three machines are always loaded with material, and he also removes the plate remnants," he continued.

“This workflow configuration has reduced our processing times by at least 50%. This 50% time saving is because we can now pendulum load and process our workflow. This means that we can cut steel plates on the extremely large bed and, in the meantime, the crane operator can load the next plate. So, as soon as the machine has cut one plate, it can move onto the next one. This eliminates noncutting times and slashes set-up times. During cutting times, the crane operator is constantly loading and unloading plates to ensure that all three stations are constantly running.

As the new Kerf plasma head is running on a 12m bed, compared to the previous 6m bed, the benefits of pendulum loading and unloading are particularly pertinent on this station.”

The typical lead times at P.P. Profiles (West Yorkshire) Ltd. are three to five days. However, the Kerf installation has eliminated bottlenecks, improved workflow and scheduling and given the company the ability to react much more quickly to customer requirements.

On top of this, the ability to service sectors where rush jobs and breakdowns are frequent is crucial to PP Profiles.

Uptime and service

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“Machine uptime and service are critical to our business. We bought a Kerf waterjet machine over ten years ago and the support has been outstanding. If we ever have an issue, Kerf will get an engineer out straight away and the problem is always resolved in less than 24 hours. What is equally impressive is its customer care; Kerf will regularly call us or popin to check that everything is running smoothly,” added Daniel Morley.

“Our previous machines were frequently breaking down and regularly disrupting production. This was a key reason for the new acquisition. The core reason for selecting Kerf was not only down to the machine capability, but also our positive experiences of reliability consumable supply and, of course, our confidence in its service support.” Another reason for investing in the new machine was quality and consistency.

“We found, with our old flame cutting machines, that dimensions were susceptible to drifting during cutting and this could lead to re-working and scrap parts. Whilst the Kerf flame machines can cut beyond 300mm thick material, we are generally cutting up to 150mm plate and, at these dimensions, drift was possible in all axes. The Kerf RUR4500 has eliminated this issue.

Precision is guaranteed, the cut quality is far superior and this is all driven by the Burny 10LCD control, which is very easy to use and program. The 7.5bar pressure through the cutting nozzles also makes the machine 20% faster than its predecessors,” Morley outlined.

The Burny 10LCD Plus CNC control unit is on each of the three cutting stations to provide flexibility and familiarity for operators. With a Windows embedded operating system, ease of use and familiarity with precise and repeatable motion control are important.

A streamlined process

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The Kerf plasma unit is powered by the Lincoln Electric Spirit II 400amp machine with UltraSharp cutting technology.

“The entire machine has an ingenious ‘plate alignment’ feature that identifies the corners of the steel plate as datum points and then uses these points to automatically adjust the cutting path via the Burny CNC platform to eliminate the need for perfect alignment.

This means that our crane and machine operators no longer have to perfectly align plates and sheets on the machine bed before cutting. This offers a considerable saving with regard to set-up times and the reduction of non-cutting time. We are cutting 12m long plates up to 40mm thick on this machine, so continuous re-alignment can be a very timeconsuming process,” added Daniel Morley.

“The Kerf RUR4500 has delivered everything we wanted and more. It has streamlined our workflow, reduced labour requirements, improved machine utilisation and uptime by 50% and increased productivity by over 20%.

Additionally, we have a reliable, well supported machine that is very accurate with the UltraSharp cutting technology and that gives us confidence to take on any future challenges,” he concluded.

A PES report By Ed Hill - reprinted from Production Engineering Solutions

Although a well-established technology for cutting sheet metal, plasma cutting can seem overshadowed by lasers. However, the latest advances from Kerf Developments demonstrate that this process can compete, not only in cutting speed and quality but importantly on cost as well. Ed Hill reports.

The systems for cutting sheet metal have evolved into a diverse range of processes over the years, but in recent times the power of lasers seems to have become the most widespread technology amongst many operators in this sector of manufacturing.

A key factor in the adoption of the laser process is the speed and quality of cut it can provide; however, lasers are an expensive capital investment, running costs can be high (particularly with the CO2 variants) and they can struggle with thicker materials.

So are there more cost-effective solutions available? One company leading the way in advancing plasma cutting technology is Rochdale-based Kerf Developments.

Founded in 2002 by Dan Taylor the company began as a service and support company repairing oxy-fuel, plasma and waterjet cutting machines.

After a few years of growing the business and establishing a reputation for excellent support, Kerf was asked if it could build a new plasma cutting machine for a customer in Northern Ireland.

Sales director Craig Walsh begins: “The nature of our work gave Kerf a really good understanding of the products that were out in the field: which ones were reliable and which ones were not.

Kerf was asked to quote for a replacement plasma cutting machine so a specification was drawn up using what we considered to be the best in class components. The machine was built onsite which led to the subsequent sale of hundreds of similar machines across the UK and Ireland.

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“Kerf is completely independent and free to choose products and services from leading global suppliers,” he adds. “Our expertise is in bringing these products together and supplying

them as a turnkey solution for customers, with packages including CNC cutting, CAD/CAM software, installation and training. We then look after the customer with effective postsale support and service.”

Kerf sells oxy-fuel, plasma and waterjet cutting machines but plasma is by far its biggest market making up around 70% of sales.

Mr Walsh continues: “Our users’ applications can be varied from small one man operations, right through to large high-volume subcontractors.

The majority of our customers tend to be involved in processing heavier materials that range from 6 - 30mm although we do have one customer with a specially designed machine that can cut 1,000mm thick material!

Our expertise is in bringing these products together and supplying them as a turnkey solution for customers, with packages including CNC cutting, CAD/CAM software, installation and training. We then look after the customer with effective post-sales support and service

"A disadvantage of early plasma cutters was that although they were fast, hole quality wasn’t great and the edge finish had a large bevel angle,” Mr Walsh explains.

“Furthermore, edge dross meant components often required a considerable amount of manual reworking after being cut, a process that was time consuming and labour intensive.

Step forward the modern high-speed CO2 laser, developed during the 1980s. The laser is a precise process that produces a high-quality edge finish and excellent hole quality.

For years lasers have been improving in speed and capability, however, they do appear to have reached their limit in terms of the thickness of material that can be cut.

While new more powerful laser sources have been developed, there is a grey area of cutting mild steel plate from 12-15mm upwards. Some laser machines can cut these thicknesses but the edge finish is not as neat as on thinner materials.”

In the thick of it Kerf has developed its UltraSharp flatbed machines which provide a quality of cut that can match and even better lasers when it comes to cutting these types and thicknesses of materials; mounted on the company’s own rigid bridge assembly and stable, downdraft cutting tables.

“UltraSharp plasma can pierce and cut mild steel up to 60mm thick, howeverit is material in the 10mmto 30mm thickness rangewhere it offers the major benefits,” Mr Walsh says.

“This thickness range posesan issue for laser cutters as they start to run out of power and cutting speeds have to be significantly reduced. This is not the case with the Kerf UltraSharp technology. As a direct comparison, the Kerf UltraSharp process will cut 25mm mild steel typically two to three times faster than a CO2 laser.”

He adds: “UltraSharp takes the well proven high definition plasma process to the next level. It enables an improvement in edge quality and offers a solution for cutting 1:1 holes in thicker materials. That is to say a good quality 12mm diameter hole in 12mm thick material.

Additionally, the process is driven by CAD/CAM software and a technology database that matches geometry to proven cut data. By using this we have deskilled the highquality plasma cutting process for the machine operator and as a result are able to offer more consistent cut quality.” Creating cost downs

So what are the sorts of cutting applications where UltraSharp really offers users benefits compared to lasercutting technology?

“There is no doubt that a high-speed laser travelling and cutting at full speed is impressive but this does come at a high price, both for the initial purchase price and the ongoing operational costs,” Mr Walsh notes.

“On thin materials, 1mm through to 6mm, you could consider laser if you had a sufficient volume of work for the machine to justify the investment levels. For a laser to be cost-effective it really needs to be fitted with a load/unload system and operate around the clock six days a week. Plus, depending on the size and power of the laser, the investment level for that might be in the region of £700,000. Additionally, the laser process may require premium grade material.

“The cost of an UltraSharp plasma machine for 3mm - 35mm applications would cost less than £100,000 for a complete turnkey installation, with operational costs of around £15 per hour. The process doesn’t require premium grade material and in some cases it provides better cut quality. Kerf can supply a machine that can cut from 1mm through to 60mm on the same machine with different models which match customers’ requirements and budgets.”

The Power Of Plasma 5

are ideal for cutting mild steel, stainless, aluminium, wear plate metals and checker plate. Kerf opts for the US made, Lincoln Electric, Burny systems for the CNC, which can work in tandem with various CAD/CAM packages, although Lantek Expert is the preferred option for new machines.

Mr Walsh says: “The UltraSharp cutting database can import geometry from multiple sources. For those using a 3D structural steel design system they can transfer files directly into the database. Similarly, DXF or DWG files can be imported into the databases. Once in the UltraSharp database the geometry is analysed and the most appropriate cut technology applied to the geometry irrespective of where it originated.

“The software can automatically nest the parts together, apply the lead-in and lead-out technology and then generate the machine efficient CNC code required. Multiple jobs for different customers can be nested together on the same plate to maximise material utilisation.”

Head control

Kerf also opts for Lincoln Electric plasma systems along with its Inova torch height control, which sets the initial piercing height of the cutting head and then constantly adjusts it as it moves over the plate to optimise the cutting process. The company also has a remote monitoring system for its machines which greatly enhances customer support.

“We are able to log into any machine around the world with Internet access and with the owner’s permission check if there are any issues. This has been very popular with our customers where we have been able to diagnose problems without having to send an engineer, saving them and ourselves time and money.”

Kerf mainly sells its plasma machines to the UK and Ireland although it will supply customers further afield if there is a local support for its machine’s control systems and plasma units.

The company prides itself on putting together bespoke turnkey packages for its customers, from small compact machines through to the large multi-bridge types installed at companies like the P.P. Group, which featured in the September 18 issue of Production Engineering Solutions.

And although the company has evolved to be a manufacturer and supplier of the latest plasma technology, its ethos is still rooted in its reputation for service and support.

Mr Walsh states: “Wherever possible we try to look at the type of products that the customer is looking to manufacture. Not all products are suitable for UltraSharp and it is essential that we and our customers understand this from the outset.

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“Effective post-sales support is what Kerf is known for. It’s where the company started and it’s still at the heart of our business. We have resisted adding additional product ranges, preferring to focus and concentrate on our core products.” he concludes.

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