“Handling was like a minor revolution”
Introduced to the market five years ago, a small welding-gas cylinder for mobile usage now trades under the name MegaTop. The French shipyard Chantiers Piriou is a major procurer of this cylinder. Ronan Morvan and Jean-René Le Torrec explain why they chose MegaTop.
on air: Tell us briefly about your shipyard.
Ronan Morvan: We build and repair fishing boats such as trawlers and longliners, as well as work boats such as barges, ferries and tug boats up to 100 metres long. We offer comprehensive solutions ranging from design and construction to maintenance and overhauling of boats. Piriou has acquired an international reputation after having built more than 300 new ships in 40 years. To remain competitive, we operate shipyards not only in Brittany, but also Nigeria, Vietnam and Mauritius. We also have a planning office in Poland. In Concarneau, 200 of our staff are engaged in shipbuilding on a total area of 25,000 square metres, 15,000 of which comprise industrial buildings. 50 welders under the supervision of Jean-René Le Torrec help construct our steel and aluminium boats.
on air: What kind of boats are you building at present?
Jean-René Le Torrec: We won three important contracts in 2009: A longliner for the South Pacific, a tuna-fishing boat for the Indian Ocean, and a ferry for use on the Gironde in southwest France. This promises a growing demand for welding gases.
on air: What do you need the MegaTop cylinders for?
Jean-René Le Torrec: The workshops are supplied with gases via the pipeline network from stationary tanks filled centrally or by means of cylinder bundles. Because this is not possible on the boats, we need to use mobile cylinders there.
on air: Why did you choose MegaTop?
Jean-René Le Torrec: This cylinder’s primary advantage is its low weight, which gives the welders greater mobility and flexibility on location. Furthermore, the cylinder can be used easily on stairs too, which is important when working on board.
Ronan Morvan: Flexibility saves time and money.
on air: What else speaks in favour of MegaTop besides its easy handling?
Jean-René Le Torrec: The integrated pressure reducer is really useful. The displays allow us to monitor gas content in real time and avoid losses. Furthermore, the integrated pressure reducer is better protected than usual against damage in case the cylinder drops; this provides good insurance against costs given our frequent use of gas cylinders.
on air: What do you think of the MegaTop’s three predefined flow rates?
Jean-René Le Torrec: The concept appeals to us. If the flow rate is continuously adjustable, the welder tends to set it to the maximum value, which usually just increases consumption without improving welding quality. The flow rate of 15 litres per minute is suitable for most welding tasks. An excessive flow of gas can also reduce the welded seam’s resistance to oxidation.
on air: Did MegaTop’s 300-bar technology play a role?
Jean-René Le Torrec: Most certainly. Though the MegaTop cylinder weighs just 40 kilograms, it has nearly the same capacity as a B50 cylinder which weighs a full 85 kilograms. The new cylinder’s easy handling is like a minor revolution, eliminating the need for the hoisting gear we had to use on board earlier in order to move heavy cylinders.
on air: Is the quality of the argon gas important?
Jean-René Le Torrec: Of course. We know that argon in MegaTop cylinders has a quality of 4.5, i.e. a gas purity of 99.995 percent by volume. Furthermore, the cylinders are equipped with pressure-relief valves preventing impurities due to humidity.
