Joe’s original question, of when were steel castings first viable, an interesting one.
I believe that the original question was directed at the production of steel castings, to be finished by machining or hand work, as distinct from the casting of ingots which would be used to make forged, rolled and drawn products.
The key word is ‘viable’. It was certainly viable for high-value items in the 1850s, but the expense of steel (prior to the satisfactory development of the Bessemer and other processes) and the considerable difficulties in making successful castings proved a barrier for many decades.
I’m not clear whether Krupp exhibited actual cast steel items at the 1851 Great Exhibition, or just ingots and products forged from cast steel ingots.
After a bit of searching, the earliest UK examples I found of products produced as steel castings were in the later 1850s. Admittedly it’s a waste of time using ‘cast steel’ as a search term. One example was a 2-ton cylinder for a hydraulic press, cast by Shortridge, Howell and Jessop of Sheffield.
The aforementioned book Sheffield Steel by K C Barraclough has an illustration of a 5-ton bell cast in 1860 by Naylor, Vickers & Co of Sheffield for a San Francisco fire station. (Peter S's post identifies Naylor, Vickers as the first UK maker of steeel castings)
The book also includes information about the high quality Swedish bar iron imported by Sheffield steelmakers. In 1869 the price could be up to £34/ton, compared with the best English wrought iron bar at £18/ton. There are c.1900 photos of the Swedish iron stocks at Firth & Sons and Jessop’s. The best stuff was stored indoors in very neat stacks, all the pieces having been cut to exact legth, corresponding to the standard crucible size. Crucible production is also covered. In 1900 William Jessop & Co were producing 3500 tons of crucibles a year. The clay was mixed and kneaded by men using their bare feet, so as to detect the presence of any sharp bits of foreign material.
In post #3 rrrgcy mentioned the introduction of centrifugal casting in England in 1809. Shortly after reading that I happened to visit a secondhand bookshop, and the ‘technical’ section contained just one engineering book, an American book on the history of foundrywork. I didn’t buy it, as it looked too broad and shallow, but I looked up centrifugal casting and it confirmed that it was invented in England, by Anthony George Eckhardt, and stated that a US firm was centrifugally casting steel railway wheels c.1900. It gave the actual date and the name of the foundry, but I can’t remember them, or the title of the book. I think the firm was in Cleveland.
Railway work probably gave a big impetus to steel foundry development. Later, development would be spurred on by the demand for big steel castings for turbines and for generator armatures.
Steel foundrywork has always been fraught with difficulties not met in iron foundries. Digger Doug has mentioned some of the problems in post #20. I’m looking at a 1930s photo of a thin-walled pump casing, as removed from the mould, and there’s probably as much metal in the various runners and risers as in the casing itself.
