SEVERSKY TRUBOPROKATNY ZAVOD [STZ], Russia

The Russian TMK-Group, one of the world’s three largest oil and gas pipe producers and at the same time market leader of the domestic pipe industry placed an order with the Italian Danieli-Group for the modernization of the seamless tube mill at their subsidiary SEVERSKY TRUBOPROKATNY ZAVOD [STZ]. STZ has already been established in 1739 and is located in Polevskoi, Sverdlovsk Region, approximately 50 km south west of Yekaterinburg.

With Danieli Centro Tube [DCT] being the main contractor, the Pilger mill will be converted into a continuous 14" seamless tube mill with an annual capacity of 600,000 tons and it will simultaneously be radically modernized. A 5-stand retained mandrel mill FQM™, a 3-stand Extracting Mill as well as a new 14-stand Sizing Mill will replace the previously operated two Pilger mills and the two subsequent sizing mills. Furthermore, nearly all of the downstream machinery will be replaced as well.

According to the cooperation agreement between DCT and FRIEDRICH KOCKS, the Hilden / Germany based company will again be responsible for the process, the design, the supply and the commissioning of the 3-stand Extractor and the 14-stand Sizing Mill. Both mills are equipped with the innovative "Star Drive" featuring individual drives for every roll.

The 3-roll stands are designed for a nominal roll diameter of 650 mm. The extractor operates with non-adjustable stands only, whereas the sizing mill with both stand types non-adjustable and adjustable ones. Important characteristics are the quick stand changing system, the in-line remote controlled pass adjustment for the adjustable stands as well as the quick roll changing system in the roll shop.

After the conversion the new mill will produce top quality seamless tubes with diameters ranging from 168 to 365 mm O.D. and wall thickness of 6.28 to 37.3 mm with excellent tolerances and proper material characteristics in accordance with the international standards to be used in the gas and oil industry.

The new mill is scheduled for start-up in 2010.