Extremely highly stressed power plant pressure pipe: Steel processor guarantees a life of more than 100 years. The hydroelectric power company TIWAG-Tiroler Wasserkraft AG is implementing a mega-project.
After the majority of the shaft pipe sections had been welded, the appraisal of Rainer Maldet, the responsible engineer from TIWAG was: “ Kremsmueller (https://www.kremsmueller.com/en/articles/10121/the-real-kremserl-mission-statement)has not just met, but exceeded our specifications. This must be thanks to Kremsmueller“s exemplary investments in machine tools and submerged-arc welding machines as well as the outstandingly qualified employees. Kremsmueller rolls the steel plates, which are up to 120 mm thick, into pipe form at its own works. Next, a submerged-arc welding machine (https://www.kremsmueller.com/en/)makes the sheet joints into a perfect cylindrical pipe section and two cylindrical pipe sections into a pipe (https://www.kremsmueller.com/en/)piece with a round seam. In the lower shaft zone, its dimensions are 4400 mm inner diameter plus 48 mm wall thickness, with a length of 6,600 mm. Kremsmueller evaluated the narrow-gap welding process in a component test for the installation welding in the shaft.
„Faults like spontaneous material fracture occur on such pipes only if the local ductility is too low. Never too close to the required elastic limit just because the strength is a few Megapascals too short“, knows Franz Mayrhofer, materials testing technology expert of voestalpine Stahl GmbH, the manufacturer of the special steel plates. TIWAG demands the best possible steel quality with high strength, so that the wall thickness of the pressure pipes can be as small as permissible, and this despite the long life specification. After preliminary trials by TIWAG,
voestalpine developed a steel that did not so far exist in this specification: alform S580/820 M with at least 580 N/mm2 as the 0.2 % yield point (for the elastic limit) and maximum 820 N/mm2 tensile strength, with very high ductile values being guaranteed at the same time. These values make it possible for the steel processor to achieve the overmatching required by TIWAG when welding. This means that the strength of the weld seam has to exceed that of the base material!
Kremsmueller was the only steel processor to confirm fulfilment of these and other specifications. To that end, the company will have to meet defined, narrow conditions that have not been met in practice so far. They are to be demonstrated for every weld seam of the entire pressure pipe through non-destructive testing, and documented. These checks will be additionally carried out by a independent third-party company by TOFD analysis on behalf of TIWAG.
Kremsmueller would like to use its significant competitive advantage to also offer outstanding solutions to other customers for highly challenging projects. After all, the future lies with metallic materials that can withstand high levels of thermal, chemical or mechanical stress. The technological trend in chemical process technology in machine, apparatus and plant construction, in the energy and transport sectors and in underground civil engineering and building construction is pointing towards extreme dimensions. The dimensions, mass and stress often exceed what has been normal so far.
(PI 12814 ca. 3.650 Zeichen)
Further information is available at www.kremsmüller.com
The family-owned enterprise, founded in 1961 and having its head office in the Upper Austrian town of Steinhaus near Wels is a complete provider for industrial plant construction. The core competences include piping, pipeline and tank construction, installation as well as instrumentation and control technology. The Kremsmueller Group has its own subsidiaries in seven countries, an employee strength of about 2,400 and in the year 2014, achieved a turnover of more than 230 million Euro. In this family-run group, foresight across generations has priority above short-term profit expectations as regards the planning and implementation of investment processes. Social responsibility, preservation of natural resources and the maximum possible independence from the financial markets characterise the management strategy.
Firmenkontakt
Kremsmüller Industrieanlagen KG
Mag. Gregor Kremsmüller
Kremsmüllerstraße 1
A-4641 Steinhaus bei Wels
43(0)7242/630-0
43(0)7242/630-1103
Gregor.Kremsmueller@kremsmueller.com
www.kremsmueller.com
Pressekontakt
redaktionsbüro gerd trommer rgt
Dipl.-Ing. Gerd Trommer
Johannishofweg 7
D-64579 Gernsheim
49 (0) 6258- 932030
49 (0) 6258-932032
presse@rgt-gg.de
http://www.rgt-gg.de
