‘P2’ cylinders united
THE construction of new-build ‘P2’ No. 2007 Prince of Wales has reached a key milestone after the three cylinders were placed together for the first time to check alignment, clearances and to ensure preparations are complete for welding to create the monobloc.
The cylinder block has been fabricated in three sections – the centre cylinder and the two outside cylinders. The mating faces have been machined to create a good fit and dowels added to control vertical and front to back movement. The assembly was strapped together so the dimensions could be measured with a Faro arm.
The three cylinders have now been tack welded together, creating the first monobloc since the 1940s. It will weigh around 5 tons when complete. As the dimensions measure up as required, the next step is a two-week long welding process, followed by up to two weeks of being stress relieved.
While proving this method is clearly vital for the ‘P2’, the A1 Steam Locomotive Trust’s next new-build project – ‘V4’ No. 3403 – will also require a fabricated monobloc cylinder. This method could also be applied to heritage locomotives, such as the National Collection’s ‘V2’ o. 4771 Green Arrow, which has a crack in its monobloc cylinder casting. Currently on display at Danum Gallery, Doncaster, the 2-6-0 is on the National Railway Museum’s list of locomotives which might be considered for a return to steam should a credible plan be forthcoming.
Fundraising for No. 2007 is ongoing. Visit www.a1steam.com or call 01325 460163 for details.