SINKOS of Poland exemplifies a prevailing trend in the steel fabrication industry: eastern European companies play growing roles in high-end applications of stainless steel, many of them trend-setters in novel uses of stainless.

SINKOS recently turned to duplex stainless steel in tanks for the chemical industry, one of the company’s core know-how areas. In so doing, SINKOS reaped considerable benefit for their chemical customer.

The customer, a major chemical company with operations in Poland, had commissioned SINKOS to fabricate and install two large tanks at their site in Poland’s Wloclawek region. The tanks are for process waste water treatment and comprise an equalizing and a reactor tank.

Relying on an industry convention, SINKOS turned to the standard materials in this application: austenitic stainless steel of grades EN 1.4301/1.4307 (ASTM 304/304L) and 1.4404 (316L). Next, they turned to Outokumpu for the materials.

After a discussion about stainless grades and their properties with Outokumpu’s Polish team, SINKOS soon changed their choice of stainless to Outokumpu’s lean duplex LDX 2101®. Pawel Chamczyk of the Outokumpu team comments, “SINKOS’s engineers immediately understood the benefits of the duplex grade and how it could produce superior tanks.”

The reactor tank was fabricated by SINKOS at the site by welding strip rolled off from coil without cutting to length. Here the top section is being mounted onto the lower section of the tank. Photo courtesy SINKOS

The main benefit reaped by SINKOS from duplex LDX 2101® was a significant saving in material through the use of thinner gauges, allowed by the high mechanical strength of duplex stainless steel. Cost savings compared to the conventional, austenitic stainless materials were substantial. In addition, duplex LDX 2101® provides an equal service life to that promised by 1.4404 in this application.

On average, duplex stainless steel can allow a 25-percent material reduction in tank wall structures, with close to 50-percent reductions in some sections.

SINKOS reaped further benefit from Outokumpu’s two-meter-wide coil: use of this extra wide coil meant less welding and welding consumables, bringing added cost advantages.

Opportunities for the chemical industry to boost competitiveness

The chemical industry is one of the main end users of stainless steel worldwide and shows steady growth. At the same time, the industry is conservative in its material choices. “The stakes are high, given the risks and consequences of corrosion and accidents,” says Bernd Beckers, explaining why the industry can be slow to look at new, competitive material alternatives. Beckers oversees the industry at Outokumpu.

“Duplex stainless steels offer a wealth of new opportunities to build more durable, safe and sustainable chemical process equipment, ranging from tanks to pressure vessels,” Beckers emphasizes. He points out that duplex stainless steels are competitive alternatives to standard austenitic grades in 90 percent of industrial applications of stainless steel. “Now is the time for the chemical industry to abandon the ‘one grade suits all’ approach and take advantage of the benefits of duplex products,” Beckers asserts.

Outokumpu is the world-leading producer of duplex stainless steel and provides grades for all corrosion environments in flat, tubular and bar products.

Complementing the duplex range, Outokumpu’s palette of stainless steel grades and products ensures optimal matches to all needs of the chemical industry – including austenitic and super-austenitic grades, and both austenitic and ferritic heat-resistant grades. Beckers adds, “Outokumpu offers industry-leading technical support, customized for each project. In addition, Outokumpu helps customers to optimize projects in terms of cost.”