When steel strip is formed into a profile, the properties of the material are changed. If  advanced high strength steels are bent, the yield strength of the material in the bend will increase.

“This is an effective way of refining our products,”states Bo Erik Pers. “Our best steel grades have been used for a number of years for producing open profiles by roll-forming. Tube manufacturers have now also started putting to use the properties of extra high and ultra high strength steels for improving the performance of their products.”

Two industries have expressly sought suppliers of advanced high strength steel tubing:

• The automotive industry
• The furniture industry

“The interest of car makers in high strength steel tubing is to meet the demands for improved crashworthiness of cars at the same or even lower weight,” explains Bo Erik Pers. “Virtually all cars made in Europe today incorporate tubes and other profiles made of extra high and ultra high strength steels.”

Better steels for more stars

We now know that the amount of advanced high strength steel incorporated into a car is usually reflected by a higher number of stars in the standardised collision safety tests on cars. In addition, increased use of high strength steels yields visible results in the fuel economy of cars. Every kilo of weight saved lowers the consumption of petrol or diesel fuel.

“We already know that even more of our best steels will be used for the next generation of cars,” explains Bo Erik Pers. “For efficient and economical largevolume production, there is actually no alternative to advanced high strength steels.”

The furniture industry is considering the use of closed-section and open profiles of high strength steels for somewhat different reasons. In this application it is mainly the strength of the material that is decisive. The world’s furniture designers gain greater freedom if they can use thinner steel that still has unaltered properties in forming.

Two-fold environmental gain

“But there are many more arguments in favour of increased use of both open and closed-section profiles in this industry,” considers Bo Erik Pers. “In all handling – storage and production as well as packaging and transport – the environmental benefit is twofold. If a manufacturer can use a lighter material, the physical strain on personnel will be greatly reduced, and energy consumption for all haulage work included in the production process will also be lower.”

Environmental benefits of this type are at least equally important to the automotive industry.

Close cooperation

SSAB Tunnplåt has actively participated in the development of new, improved production methods for both open and closed-section profiles. Close cooperation with customers who endeavour to remain at the leading edge of their industry has resulted in a number of entirely new products.

“By combining our knowledge of advanced high strength steels with the competence of customers in profiling and tube production, we have succeeded in developing products that have already gained practical application in the market,” states Bo Erik Pers.

He mentions Fainsa and Grammer, two of the companies nominated for the Swedish Steel Prize 2004 as typical examples. Both of these bus seat manufacturers competing for the Prize used ultra high strength steel tubes for producing seats that conform to all of the safety requirements, without the seat weight being affected.

“In both of these cases, cooperation between SSAB and tube manufacturers has opened new opportunities for the end customer,” considers Bo Erik Pers. “Both parties contribute to the steel product used acquiring a much higher value to the end user of the material.”

Other interesting examples of how tubes of advanced high strength steel can be used can be found at the French tube manufacturer Vallourec. The company produces hydroformed tubes and preassembled components used by the automotive industry. The dashboard console (see photo above) provides an illustration of this.

Tubes and profiles are usually delivered in standardised sizes. Although many customers naturally have special requirements, Bo Erik considers that the products offer major benefits especially as standardised elements.

Opportunities will be put to wider use

“Standard tubes of ultra high strength steels can be used as elements in anything from individual structures to products in large-scale serial production,” he says. “For many years, designers around the world have clamoured for thin-wall tubes of advanced high strength steels. Now that such tubes are available, I am certain that the opportunities offered by the tubes will be put to use much more widely than merely by companies in the automotive and furniture industries”.