Irish manufacturing company Dromone Engineering — established in 1978 and now employing over 140 people — took a decision early on not to focus on providing a sub-contract machining service but instead to develop, manufacture and market its own product lines.

It has since become an industry leader in tractor pick-up hitches for the agricultural sector and excavator quick couplers for the construction sector.

The company also resolved to keep its manufacturing base in Oldcastle, County Meath (just north of Dublin), and not move production to a low-wage country in Asia or elsewhere; and while this is ‘an admirable objective’ that many firms achieve, there was a particular obstacle in Dromone Engineering’s case.

Despite having to provide top-quality products for applications in the industries it serves, price negotiations do not come down to the nearest euro, but to the nearest cent.

From the start, the dilemma of manufacturing in a first-world country and trimming prices to two decimal places has focused the minds of the firm’s directors and shaped their capital investments.

In 1999, for example, they were among the first manufacturers to harness the productive power of laser cutting with the purchase of two 3.5kW CO2 machines built by the Swiss company Bystronic — and supplied by Coventry-based Bystronic UK Ltd (www.bystronic.com) — for profiling mild steel sheet up to 4 x 2m.

In March 2019, these long-serving machines, which had been extremely reliable, were replaced by more up-to-date technology in the form of a Bystronic ByStar Fiber 4020 10kW fibre laser cutting centre.

This was delivered as a turn-key package, automated by the addition of a bespoke material-handling system and a tower store that accommodates up to 96 tonnes of material on 17 levels.

Dromone Engineering’s managing director, William Egenton, said: “We export almost all of our products to 39 countries, either directly to ‘blue chip’ customers like JCB, Volvo, Massey Ferguson, Claas and Kubota, or via a world-wide distribution network servicing other OEMs, dealer networks and rental fleets.

“Customers in the West in particular appreciate the fact that we manufacture safety-critical products tailored to their specific needs in Ireland, and they are impressed when they visit us; but to make the operation financially viable, we have to use a high level of automation.

“That is why over the last five years we have invested 5 million euros in not only the latest laser cutting technology but also three Panasonic robotic welding cells, four Mazak horizontal- and vertical-spindle machining centres and enterprise resource planning software.”

Enhanced quality and output

Ollie Devine, Dromone Engineering’s maintenance and ‘capex’ manager, said: “With some forms of automated production such as welding, component quality is raised compared with manual techniques due to the better repeatability of the process.

“In the case of the Bystronic laser cutting centre — and other CNC machine tools, for that matter — high quality is already built in.

“Automation brings more-efficient delivery of raw material and unloading of finished work, minimising idle times and maximising efficiency.”

The increase in cutting output at Dromone Engineering has been dramatic.

The single fibre machine — fed from the sheet storage and retrieval tower that was purpose-built to be exactly 5.54m high, so that it fitted beneath the factory roof — produces 30% more than both of the previous CO2 machines combined.

This performance is not only down to the speed of fibre laser cutting but also because previous sheet replenishment — though automatic — was relatively slow; it was achieved using swing-arm Byloaders to transfer material from pallets to the respective CO2 machines and to offload the laser-cut sheets.

Overall, utilisation of the machines was only 50-60%.

In contrast, the tower system has two handling carriages.

One transfers a laser-cut sheet to a twin offload table arrangement at the back of the ByStar Fiber, while the other (more or less) simultaneously picks up a new sheet from the store and loads it onto the machine’s shuttle table; from here, it is immediately transported into the cutting area.

Furthermore, little laser cutting time is lost and machine utilisation is around 90%; and labour cost is saved by the operator being required to run the cell for only 2.3 shifts rather than three to achieve the required output (this is currently sufficient for 11,000 tractor line products and 6,000 construction line products a year).

The offload tables themselves are another example of Bystronic’s bespoke approach to supplying customers with systems that exactly suit their requirements.

The tables were purpose-built to be of different widths and heights and to run on rails set in the floor, allowing one to pass beneath the other so that both can sequentially access a ‘shake-out’ area.

Mr Devine said that a single table would have held up fibre laser profiling, as the fast speeds achieved using a 10kW source would often have resulted in the next machined sheet waiting for the shake-out station to become free, wasting valuable production time.

Even with the twin-table set-up, the productivity of the ByStar Fiber is so high that two people rather than one are often needed to remove components (depending on how many there are) quickly enough from each sheet before the next one arrives.

A video showing many of these features in action can be viewed at the Web site (dromone.com new-laser-investment).

Higher speeds

Mr Devine added: “We process mild steel from 3 to 20mm thick on the ByStar Fiber.

“The 10kW fibre laser cuts thinner gauges three- to four-times faster than a 3.5kW CO2 source, although the speed advantage diminishes as the material thickness increases.

“This cutting performance translates into reductions in production cost per part of two thirds on thinner components, and one third on thicker parts.

“This is highly beneficial when chasing cents on the price of one of our finished products.

“Compared with CO2, fibre cutting is a more stable process, less maintenance is required — helping to increase up-time — and running costs are lower, in terms of both consumables and power.

“Another benefit of the new system is better air quality in the factory, as the automation has eliminated a lot of diesel fork-lift movements, while extra space on the shopfloor makes the kitting area more spacious and ergonomic, so there are also health-and-safety advantages.”

A Bystronic solution was chosen for this project, partly because the compact configuration fitted into a corner of the Oldcastle factory that was previously unused; six machine tools will now fit into the area where the CO2 lasers had been, thereby enabling Dromone Engineering to further develop the lean-manufacturing and flow-line practices that it embarked on a decade ago.

Mr Egenton concluded: “The relationship between our engineers and those at Bystronic UK in Coventry has been highly co-operative.

“At the outset, the good communication facilitated the precise design of a laser cutting cell to suit our needs.

“During installation, Bystronic made sure that there was a seamless transfer from the old process to the new one; for a two-week period, they both ran side by side.

“After we swapped over, we were in production straight away.

“It is unusual for such a complex system to be completely problem-free from the outset; and since commissioning, the supplier’s service has been of a high level.

“This is important to us, as we now have only one laser machine — and therefore no production redundancy.”