Steel locos?

[Trackbedjolly]

Apparently the early steam locos and bridges were made of steel-I always thought locos were iron with wooden or iron bridges
'Darlington MP Peter Gibson said:
'"Locomotion No.1 is an essential part of our town’s identity, cast in steel on the pillars that hold our railway bridges up...."'

Future plans agreed for Locomotion No. 1

Darlington Borough Council (DBC) and the Science Museum Group (SMG) have reached an agreement that will see the historic engine Locomotion No.1 return to Head of Steam in the first half of 2025 – the bicentenary year for the iconic Stockton & Darlington Railway.

www.darlington.gov.uk

Anyone else agree with me?

 

[ac6000cw]

(I'm not a expert on this) The Bessemer process, which allowed large quantities of steel to be produced at low cost, wasn't developed until the late 1850's (well after the 1840's 'railway mania' in the UK) - steel was a costly material up to that point, so generally bridges would not have been constructed from steel before then (too costly). If not built from stone/brick then wood/cast iron/wrought iron (in order of increasing cost) would have been used instead. Once steel became cheap enough it generally became the preferred material over iron for railway bridge building as it has generally more suitable properties for that application.

 

[Bevan Price]

(I'm not a expert on this) The Bessemer process, which allowed large quantities of steel to be produced at low cost, wasn't developed until the late 1850's (well after the 1840's 'railway mania' in the UK) - steel was a costly material up to that point, so generally bridges would not have been constructed from steel before then (too costly). If not built from stone/brick then wood/cast iron/wrought iron (in order of increasing cost) would have been used instead. Once steel became cheap enough it generally became the preferred material over iron for railway bridge building as it has generally more suitable properties for that application.

Yes, a lot of early bridges used wood. which was sometimes prone to rotting, or sometimes unable to accept heavier loads as trains got bigger, and the bridges had to be rebuilt / replaced.

 

[DerekC]

I think Peter Gibson MP needs a lesson on iron and steel and the differences between them. Cast iron and wrought iron were the materials used by the first successful locomotive railways until mass produced steel became available in the late 1850s.

I think it's true that railway development took off when it did, very largely because the materials became good enough to build wrought iron rails that didn't break under the weight of a locomotive and boilers rivetted together from wrought iron plates that didn't (often) burst under the pressure of steam. Early railways used cast iron rails for cheapness, but they broke too frequently - and the rails could only be cast in short sections. Cast iron was used for bridges and as long as it was kept in compression (as in the arched bridge at Ironbridge) it was fine. But there were some spectacular failures when cast iron beams were used.

It's worth remembering that steel has been around since it was first made in India in about 400BC - but only in small quantities and at very high cost. There's an interesting article about it here:

https://www.popularmechanics.com/technology/infrastructure/a20722505/history-of-steel/

Here's a few extracts:

To know steel, we must first understand iron, for the metals are nearly one and the same. Steel contains an iron concentration of 98 to 99 percent or more. The remainder is carbon—a small additive that makes a major difference in the metal’s properties. In the centuries and millennia before the breakthroughs that built skyscrapers, civilizations tweaked and tinkered with smelting techniques to make iron, creeping ever closer to steel...........Around 1,800 BC, a people along the Black Sea called the Chalybes wanted to fabricate a metal stronger than bronze—something that could be used to make unrivaled weapons. They put iron ores into hearths, hammered them, and fired them for softening. After repeating the process several times, the Chalybes pulled sturdy iron weapons from the forge...
What the Chalybes made is called wrought iron, one of a couple major precursors to modern steel. They soon joined the warlike Hittites, creating one of the most powerful armies in ancient history. No nation’s weaponry matched a Hittite sword or chariot.

Steel’s other younger sibling, so to speak, is cast iron, which was first made in ancient China. Beginning around 500 BC, Chinese metalworkers built seven-foot-tall furnaces to burn larger quantities of iron and wood. The material was smelted into a liquid and poured into carved molds, taking the shape of cooking tools and statues.
.... Around 400 BC, Indian metalworkers invented a smelting method that happened to bond the perfect amount of carbon to iron. The key was a clay receptacle for the molten metal: a crucible. The workers put small wrought iron bars and charcoal bits into the crucibles, then sealed the containers and inserted them into a furnace. When they raised the furnace temperature via air blasts from bellows, the wrought iron melted and absorbed the carbon in the charcoal. When the crucibles cooled, ingots of pure steel lay inside.

 

[DelW]

I think Peter Gibson MP needs a lesson on iron and steel and the differences between them. Cast iron and wrought iron were the materials used by the first successful locomotive railways until mass produced steel became available in the late 1850s.

To be fair, in the linked report, Peter Gibson doesn't seem to be implying that either Locomotion itself, or the bridges it used, were built of steel. He just says that images of Locomotion are cast into steel bridges, which might have been built in much more recent time, along with other local buildings:

Darlington MP Peter Gibson said: "Locomotion No.1 is an essential part of our town’s identity, cast in steel on the pillars that hold our railway bridges up, carved in stone on memorials to our fallen, cast in bronze on the weathervane atop our market hall clock tower, and embroidered onto the strips of our footballers.