Steel Mill Robots: From Spoon Samples to ABB Arms

Few workplaces are as hard on people as a melt shop, and that gives the steel mill robot a clear job: stand at the furnace or the ladle so a worker does not have to. In September 2026 the refractory maker RHI Magnesita described a robotic system it put into service at the caster of an Indian steel plant in 2025. It changes ladle shrouds, feeds casting powder, measures temperature and takes samples around 350 tonne ladles. This post looks at how those jobs were done by hand, how probes and the first robots took over, where ABB robots fit today, and what changes as Europe replaces blast furnaces with electric ones.

The electric arc furnace at Georgsmarienhütte steelworks in Germany in operation, 2005. Photo: GMH official / Wikimedia Commons (CC BY-SA 3.0)

How steelworkers sampled the melt by hand

For most of the twentieth century, checking the steel meant using a spoon. A worker dipped a deep steel ladle on a long handle into the molten metal and poured it into a small test mould, which gave the lab a bar four to eight inches long. Photos from the Fagersta ironworks in Sweden in 1967 show the job at an open hearth furnace: one man reaching toward the glare with a long tool while a second watches, then a worker crouched over the hot sample in a shower of sparks. An open hearth heat took 10 to 12 hours, so there was time for several tests, and each one put a person in front of an open furnace door.

Taking specimens at an open hearth furnace at the Fagersta ironworks in Sweden, 1967. Photo: Pål-Nils Nilsson / Wikimedia Commons (public domain)

Faster steelmaking forced faster measurement. The first LD converters, which blow pure oxygen onto molten iron, started up at VÖEST in Linz in November 1952 and in Donawitz in May 1953. A blow lasts about 20 minutes, and the temperature is measured and samples are taken near the end. Disposable immersion probes became the standard tool: a sensor or a small sample chamber on the tip of a long lance, held in the bath for a few seconds and then thrown away. A 1977 US patent for a new sampler called the old spoon method wasteful in time and material, and noted that it let air reach the metal and change the sample's chemistry. The probe replaced the spoon, but a person still held the lance.

Taking specimens at the Fagersta ironworks open hearth shop in 1967, with sparks flying from the hot metal. Photo: Pål-Nils Nilsson / Wikimedia Commons (public domain)

Two kinds of automation followed. Converters got sublances, a second lance that dips a probe into the bath without tilting the vessel or stopping the blow. Danieli Corus, active in converter steelmaking since 1977, counts more than 130 sublances installed worldwide. Robots arrived later, and first at the cooler end of the mill. In the summer of 2003, Corus installed two ABB IRB 6400 FoundryPlus robots at its Teesside Beam Mill to spray identification codes onto hot steel sections in the cooling banks, with paint that works at up to 800 degrees Celsius and a six second cycle. The mill had tried chalk, hand stamping, labels and paint stencils before.

One of two ABB IRB 6400 FoundryPlus robots that spray identification codes on hot beams at the Teesside Beam Mill. Photo: ABB

Steel mill robots at the furnace today

The hottest jobs are now going to robots too. Danieli sells Q-Robot Melt, an articulated robot with a water-cooled lance that takes temperature readings and chemical samples from electric arc and ladle furnaces, so operators spend less time in the heat, noise and fumes. The RHI Magnesita system in India works around the caster and uses sensors and vision to watch the process in real time. In Korea, POSCO's chief digital officer Lim Chi-hyun said on September 29 that the company runs 11 model "intelligent factories" at its Pohang and Gwangyang works and has already run fully automated steelmaking operations from start to finish with no human involvement.

The new direct current electric arc furnace at Arbed's Differdange mill in Luxembourg during commissioning, November 1995. Photo: European Coal and Steel Community / Wikimedia Commons (CC BY-SA 4.0)

ABB robots have a documented record in this work. Corus reported that the Teesside marking robots ran at more than 99.9 percent availability, and it planned two ABB IRB 6600 robots in 2005 to label sections further down the line. At the Acciaierie d'Italia steel plant, the EU-funded ROBOHARSH project mounted an ABB robot with foundry protection and a 245 kg handling capacity on a movable platform to maintain the ladle's sliding gate during continuous casting. Done by hand, that job took about 30 minutes in heat around 70 degrees Celsius and meant lifting plates of about 20 kg. Programs for cells like these are usually built and checked first in RobotStudio.

The second Teesside marking robot at work in the cooling bank after the hot saw. Photo: ABB

For new projects, ABB's candidates are its large arms with Foundry Plus 2 protection, which is rated IP67 and withstands high pressure steam washing, useful in a shop full of dust and spatter. The IRB 6700 family, renewed in 2023 as the IRB 6710, 6720, 6730 and 6740, covers payloads from 150 to 310 kg and reaches from 2.5 to 3.2 metres. One of these could hold a probe lance the way Danieli's robot does, but ABB has not announced a sampling cell of its own, so that remains a possibility. ABB also sells drives and motors to steel mills. In September 2026 its partner iconsys won a multi-million-pound order for ABB ACS880 drives and motors for a new coil box and crop shear at a UK steel mill.

A white ABB foundry robot works in steam at a Bühler die casting cell. Photo: ABB

What the next steel mill robot will have to handle

The next wave of work comes from the move to electric steelmaking. On September 20, Hüttenwerke Krupp Mannesmann shut down blast furnace A in Duisburg after 53 years; an electric arc furnace of 2.5 million tonnes a year is due to replace it in 2029. Tata Steel's electric arc furnace at Port Talbot, backed by a £500 million UK government grant, has slipped to late 2028 or early 2029 because of delays in its grid connection. Every new furnace needs temperature readings and samples for each heat, and the builders can plan robot positions into the shop from the start instead of squeezing them onto old platforms.

Clydesdale tube works in Scotland, where two 70 tonne electric arc furnaces replaced open hearth furnaces, around 1975. Photo: European Coal and Steel Community / Wikimedia Commons (CC BY-SA 4.0)

Heat and variety make the job hard. A robot near a furnace needs cooling, shielding and protected cables. Probe cartridges are consumables, so a sampling cell needs an automatic magazine or a person to reload it. Each shop has its own furnace door, ladle height and crane traffic, so cells tend to be engineered for one site, which keeps costs high for smaller mills. Our post on ABB foundry robots and gigacasting looks at the same kind of robot next to hot aluminium. For people at home the link is indirect: the steel in a car body or a washing machine drum started as a heat that someone, or something, sampled and measured.

A machine working at the open door of an electric arc furnace, 1976, from a Deutsche Fotothek series on steel metallurgists. Photo: Eugen Nosko / Deutsche Fotothek via Wikimedia Commons (CC BY-SA 3.0 DE)

Skills and safety set the pace. At Teesside, five mill engineers took ABB's programming course so they could move the robots by hand in an emergency, and POSCO says it is turning the tacit knowledge of its most skilled operators into data for AI. Robots in a melt shop also need safe zones that keep people out while the arm moves and let maintenance crews in when it stops, which ABB controllers handle with SafeMove. The Corus mantra at Teesside, quoted in ABB's case study, was "keeping people away from the process".

An ABB robot beside a melting furnace in the aluminium casting shop of Hermeta in Asperen, the Netherlands. Photo: ABB

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