When Kettering-based Prosaw Ltd (
www.prosaw.co.uk) was asked to provide a system that could saw through 3m-diameter bundles of heat-exchanger tubes, its in-house technical design team went to work.
It emerged that the tube bundles come from shell-and-tube heat exchangers — most frequently used in oil refineries and chemical plants — that are packed with tubes, with one fluid passing through the tubes and another passing over them. When the tubes need to be replaced due to corrosion, the first thing to be done is to saw through the entire bundle.
In response to this challenge, Prosaw designed a special heavy-duty machine — featuring a horizontally mounted bandsaw fitted with a 67mm-wide blade — that can saw through a 3,000mm-diameter tube bundle in less than a third of the time taken using conventional sawing machines.
The bandsaw is pre-programmed, but its feed rate varies to take account of the constantly changing profile of the tube bundle as sawing takes place (with no operator involvement at this stage).
Prosaw sales director Robert O’Brien says: “We are very proud of our achievement in carefully designing and producing this remarkable system, which delivers a massive reduction in process time compared with traditional methods, while
simultaneously achieving a significantly extended blade life.”