“Steel is made by melting scrap with molten pig iron from the blast furnaces together with fluxes and oxidising materials. At Ravenscraig, steel can be made either in the open hearth melting shop or in the basic steelmaking plant” – Leaflet produced by Colvilles Ltd, 1967
The Open Hearth process of making steel is so-called because the molten iron, scrap and limestone are charged into shallow steel making areas (hearths) and then exposed (open) to the flames. This was an extremely slow method of conversion, taking up to 10 hours to complete. It was withdrawn from service in the UK by 1980.
The Basic Oxygen Steelmaking (BOS) process was first introduced into Ravenscraig in 1964. This was a more efficient way of making steel:
“On arrival at the steelplant liquid iron is poured from the torpedo cars into ladles. The first process is for the iron to be treated in a de-sulphurising unit. The steelmaking vessel is then tilted to receive scrap followed by the iron… Pure oxygen is top blown into the vessel and argon/nitrogen bottom blown. Lime, added as a flux, helps to form a slag to collect the impurities. When the correct analysis has been achieved the liquid steel is tapped into a ladle. The production cycle time is 31 minutes.” – Ravenscraig Works, a British Steel produced leaflet.
Basic Oxygen Steelmaking
Ravenscraig
© Owens Ind & Comm Photographs
Comments & Quotes
“I can tell you a good story – A group of steelmen went down to Wales to show the workers down there the strip process [from Ravenscraig].
After they got back a group of Welsh steelmen came up to the site claiming that they hadn’t been given the correct process, that they must have missed something out, or deliberately told them the wrong thing, as the steel they had made was not right. They tried to say that we must have used different fuel or different chemicals and kept asking what it was we did that made our steel so strong.
There was this wee guy over in the corner and he pipes up “We dinnae gie ye the wrang process. The formula is right. I’ll tell ye whit the difference is. The difference that makes the good steel in Scotland is the water. The Soft Water!
…And he was right you know!”
Peter Dougan, The Craig, the Industry and You project