The Royal Ordnance Factory, ROF Patricroft, was an engineering factory was classified as a Medium Machine Shop. It was located in Patricroft, near the town of Eccles, in the City of Salford, Greater Manchester, England, adjacent to both the Liverpool and Manchester Railway and the Bridgewater Canal.
The Ministry of Supply took over an existing engineering works, The Bridgewater Foundry, founded by James Nasmyth and Holbrook Gaskell, owned by the locomotive manufacturer Nasmyth, Gaskell and Company. They had ceased manufacturing locomotives in 1938 but continued, on a smaller scale, making steam hammers and machine tools. The company ceased trading in November 1940.
The Ministry of Supply took over the works, on 1 June 1940, to convert it into a Royal Ordnance Factory. Staff from the Royal Arsenal, Woolwich, acted as agents for the Ministry of Supply. It reopened as an ROF in February 1941.
The site consisted of a square mill-like building, known as The Tower, and various surrounding buildings including a machine shop, a foundry and a blacksmith's shop. It remained in use as an ROF until the late 1980s.