One-fifth productivity increase when laser cutting thinner materials

Inishowen Engineering

Irish subcontractor Inishowen Engineering, which specialises in sheet metal fabrication and CNC machining, reports an increase in laser cutting speed of 20 per cent when processing mild steel sheet up to 4 mm thick. It follows the replacement in mid-2015 of the company’s Bystronic 6 kW CO2 laser profiler with a similarly powered fibre laser cutting machine from the same supplier.

Michael McKinney, Inishowen Engineering’s managing director commented, “We have a policy of regularly replacing our production machines and when our 2007 CO2 laser machine came up for renewal last year, fibre technology was the obvious choice.

“It not only cuts thinner material significantly faster but also costs less to run and service, so we will enjoy financial savings for years to come.

“The latest, high power fibre sources also allow heavier gauge materials to be processed nearly as efficiently as on a CO2 machine. We regularly cut mild steel up to 12 mm on the Bystronic BySprint Fiber 4020.

“On even thicker materials, up to 25 mm, we use the BySprint CO2 machine and a plasma cutter, so we have all requirements covered.”

Inishowen Engineering specialises in supplying complete assemblies. In addition to the profiling division, the firm runs a welding department and a precision machining facility populated with numerous large machining centres and lathes. Mr McKinney explained that only 30 per cent of the profiling division’s output is delivered either untouched or after a visit to a Bystronic press brake. The remainder undergoes fabrication and often the inclusion of machined components.

Customers are to be found across the construction industry taking delivery of structural steelwork, staircases, railings, excavator attachments and much else. Marine equipment includes stainless steel conveyors and sorting tables, while crushers for the quarrying industry are an important product line. The agriculture sector has continued to be a mainstay, as it was in 1994 when Mr McKinney started the company to service farming equipment.

Five years later he bought his first plasma cutting machine and began subcontract supply of parts to agricultural equipment manufacturers. Business grew steadily and so did the expectations of Inishowen Engineering’s customers, which by then included forklift truck manufacturers that were demanding ever more accurate components to minimise the need for fit-up during assembly.

This demand was the trigger for the subcontractor to install its first laser profiler, a 4 metre by 2 metre sheet capacity BySprint 4020 CO2 model equipped with ByTrans automated sheet loading and unloading. Its purchase in 2007 followed a six-month appraisal of alternative fibre laser cutters on the market, culminating in a visit to Bystronic’s factory in Switzerland and cost-per-part production trials at the machine builder’s Coventry subsidiary.

Laser cutting resulted in a quantum step forward not only in component accuracy but also in edge quality, evidenced by favourable feedback from the subcontractor’s customers. About that time the last recession took hold and demand halved. Mr McKinney had a simple and highly effective solution; he doubled the customer base. At the same time he instigated lean manufacturing procedures and by 2011, turnover had returned to pre-recession levels.

Even by 2008 it was clear that the strategy was working. What was also evident was the high standard of service back-up that Bystronic UK was providing. As Inishowen Engineering was being asked to supply more and more folded parts, the subcontractor needed to buy a press brake and decided on a Bystronic 3-metre / 150-tonne Xpert model. It has since standardised on this supplier for all its bending requirements.

Two years later, two Bystronic Xpert 400-tonne / 4-metre press brakes were installed in tandem on the shop floor of the Drumfries factory, on the Inishowen peninsular in County Donegal, Republic of Ireland. It allowed the subcontractor to fold components up to twice as long as the previous 4-metre maximum, greatly increasing supply of fabrications to crushing and screening equipment manufacturers that were asking for larger components to minimise welding.

2010 also saw the installation of a second laser cutting machine, another BySprint CO2 4 metre by 2-metre capacity model but this time equipped with a powered ByLoader arm to assist manual handling of sheet and plate onto and off the shuttle table.

The rationale for this configuration was twofold. First, it was practical for production of component types in batch sizes that do not lend themselves to automated production. Secondly, it allowed efficient use of an operator’s time, as one person is able to look after the manually-loaded laser cutter as well as the automated cell.

Last year, in addition to installing the fibre laser cutting machine and equipping it with the existing ByTrans to automate sheet handling, Inishowen Engineering took delivery of Bystronic’s smallest press brake, the recently-launched Xpert 40-tonne / 1-metre capacity model.

Sixty per cent of Inishowen Engineering’s parts are less than one metre long, so Bystronic’s introduction of the machine had been eagerly awaited. There had been reluctance to source a machine from elsewhere due to the subcontractor’s policy of remaining with a single supplier for each machine category.

Mr McKinney advised, “The Xpert 40 is at least one-third faster than larger press brake models and the tooling is interchangeable. The added speed translates into higher productivity when folding our smaller parts.

“In addition, the machine does not draw much power, just 7.5 kW instead of typically 30 kW for a big press brake, so we benefit from lower electricity bills as well.”

The family-run subcontractor is looking forward to a bright future, with a 250,000 ft2 purpose-built factory due to open on the existing site by 2020 that will dwarf the current 75,000 ft2 premises.