UK Steel, the trade association that represents the interests of the UK steel industry, says that Chinese rebar sold in the UK has small amounts of other elements added so that it can be classed as ‘alloy’ and thus qualify for an export tax rebate.
A significant – but unknown – proportion of the Chinese rebar sold in the UK contains boron in excess of 8 parts per million (ppm). Samples have been tested with boron at 30 ppm. The Welding Institute has now issued guidance that rebar containing boron in excess of 5 ppm requires changes from the normal welding techniques used.
The only way of telling which Chinese rebar contains boron is to test every single bar. Otherwise, fabricators cannot tell which welding technique needs to be used, experts advise. As such tests are not generally undertaken, there is thus a real risk that welded structures using Chinese rebar could fail, UK Steel warns.
Director Ian Rodgers said: “Our advice to any fabricator with stocks Chinese rebar is that they should urgently identify any bars containing more than 5 ppm of boron and segregate them. These bars should not be used in structures requiring welding until staff have been trained in the specific welding techniques required.”
He added: “Coming on top of the quality problems affecting some Chinese bars last year, this latest development does raise questions about the cost effectiveness and safety of sourcing outside of Europe.”