The Flying Scotsman locomotive has been undergoing major refurbishment in preparation for its 75th birthday in May 1998 when it is hoped the engine will be steamed and pulling trains again. The boiler had serious wear problems and TWI was asked for advice in remedying them.
The Flying Scotsman was designed by Sir Nigel Gresley in 1923. It was one of the fastest locomotives of its time and made the first non-stop run from London to Edinburgh. Two areas of the boiler needed immediate attention. These were the backhead and the copper firebox. Due to the nature of the boiler, hot water circulates very rapidly around the components inside. The water often contains grit which, over time, caused erosion in the corners. Also, pressure changes within the boiler caused flexing, leading to small cracks and thinning of the wall material.
To repair the steel back-head, a traditional arc process was used. The worn material was ground away and restored to its original dimensions by manual metal arc welding. However, to attach a new flange to the copper firebox, it was decided to employ the much newer electron beam (EB) process. This meant the repairs could be completed much more rapidly compared to conventional welding techniques. This steam locomotive now contains the first EB-welded component anywhere in the world.
To find out more about either traditional or innovative methods of welding, contact Derek Patten in the Arc Welding section or Chris Punshon in the Electron Beam Department.