Iron has been made in Britain for almost 3000 years. Dating back to 800 BC, the beginning of the Iron Age, many relics and remains from this period can still be found within some parts of North Lanarkshire.
Iron was made at Ravenscraig but not as an end product. Instead it was produced to provide the necessary ‘hot metal’ needed to make steel. The iron was made in blast furnaces, huge hollow structures where raw ingredients were heated to 1,300 degrees Celsius. Ravenscraig ultimately had three blast furnaces, two of which were in use at any given time, the third being either on stand-by or being ‘re-lined’, ie having its internal brick work renewed.
Furnaces number 1 and 3 were the first bell-less top charging systems of their kind to be installed in a UK steelworks.
Iron-making is a continuous process, and the blast furnaces would be kept fired for up to two years before being refurbished. The raw materials of coke, sinter and iron ore were fed into the top of the furnace, and blasts of hot air were pumped from the bottom, heating the coke sufficiently to melt the iron content.
When making sinter, a by-product of red dust would float into the atmosphere with the ability to cover everything it came into contact with, including drying laundry!
At earlier pig iron works such as Summerlee in Coatbridge the iron was cast as ingots called ‘pigs’. The pigs would then be re-heated to make castings or to be converted into malleable iron or steel. However, this was inefficient because it took a lot of energy to re-heat the iron. By the time Ravenscraig was built in the 1950s it was standard practice to move the iron from the blast furnace to the steel plant while it was still molten, usually in railway ‘torpedo cars’, so-called because of their shape.
Comments & Quotes
“Each section in a vast steel works was its own little world, its own odd rules, customs and habits. One I recall at a meeting was ” My faither done it that way and his faither as weel so that’s how we dae it”. In response to one of many management bids to improve efficiency! It concerned adding additives to the furnaces. Rather than shovel additives in they were to be weighed after the lab had sent down the precise quantities and added with a mechanical ladle/charger! But no, the guys had always done it “that way” and always got it right.”
Moonbeam – The Hidden Glasgow Forums