Corus managers suggested this week that a freak explosion deep within the molten core of a blast furnace at its Port Talbot plant could have been to blame for the accident which showered superheated metal over nearby workers.
A spokesman for the company told The Engineer that its first analysis suggests the unprecedented event could be the cause of the disaster that killed three employees and critically injured another five.
Industry experts and the Anglo-Dutch steelmaker agree that an explosion within the molten metal itself is virtually unknown.
Although Corus has not offered an explanation for the cause of the explosion, a spokesman said the resulting force caused an expansion joint around the furnace to fail, allowing several tonnes of molten iron, coke, sinter, ash and gases to escape in all directions.
‘What appears to have happened is that a tremendous explosion occurred within the furnace, lifting the top two-thirds at the expansion joint, which runs round the furnace circumference. This type of incident is believed to be unprecedented in the world’s ironmaking industry.’
Steel manufacture expert Dr Tony Bryant of the University of Sheffield agreed that an explosion within the molten core was extremely rare.
‘The industry’s safety record is very good. These processes are carefully monitored. What we’ve seen happen at Corus is virtually unknown and so there is no data to make any sort of judgment without more evidence.’
Allegations that the breakout of molten metal at Port Talbot was in part due to a lack of maintenance of the furnace have since been strongly denied by Corus.
The spokesman said there was no indication that the furnace refractory lining failed, which could have led to hot metal burning through the furnace wall.
‘We can say categorically there was no degradation of the lining and nothing forced itself through the shell of the furnace. Contrary to reports, furnace number five has not had several breakouts over the past few years. It has had none since 1994.’Last month the company completed a review of the furnace and concluded that it could continue to operate until 2005 before requiring a reline.
‘There was some local pressure at the time for fume arrestment equipment and extra investment, but the upgrade was put on hold because it would have meant a rebuild, stopping production,’ said the spokesman.
Despite the company’s claims, a 30-year veteran of the steel industry and local councillor disagrees. local Labour Caerphilly councillor and former steelworker Ray Davies told The Engineer that this latest explanation offered by Corus shows maintenance was an issue.
‘I have seen situations where expansion joints had moved and the explanation sounds realistic. These things happen if someone fails to check the amount of gas going in. There are many gases involved including carbon monoxide, a by-product.’ The investigation remains in the hands of the Health and Safety Executive and South Wales Police. Their task is not easy because the immediate area around the furnace is still not considered safe.
According to the HSE, the furnace still contains large quantities of material which continues to ‘react’. As well as a cooling down period, the structuralstability of the furnace and the surrounding pipework and buildings have to be assessed and made safe for investigators. This could take two to three weeks.
Teams have been established to secure physical, documentary and computer evidence and the process of interviewing the large numbers of witnesses has begun, said the police.
Dr Mark Carr, managing director of Corus Strip UK has reassured the workforce thatneither the blast furnace nor Port Talbot will be closed down. Planning for the repair of the furnace has already started.
He said that Port Talbot’s furnace number four, increased output at the Llanwern plant and in-house stocks of metal products would ensure orders are met.The funerals of the three victims, Andrew Hutin, 20, Stephen Galsworthy, 25, and Len Radford, 53, took place this week.