BAOJI PETROLEUM STEEL PIPE, China

Friedrich Kocks GmbH & Co KG in Hilden / Germany received an order to supply a Stretch Reducing Block [SRB] and a Rotating Hot Saw [RHS], which are the core of the new continuous production plant. The order was placed by China National Petroleum Corporation [CNPC] within the frame of the new construction of a welding tube plant at its subsidiary Baoji Petroleum Steel Pipe Co., Ltd. [BSG] in Baoji / China.

CNPC is an internationally operating energy company with works in 29 countries of the world and China's largest oil and gas producer.

Baoji Petroleum Steel Pipe was originally founded in 1958 and today it is one of the most important companies of CNPC. At that time, BSG was the first Chinese manufacturer of tubes using the submerged arc welding method and nowadays produces 1.25 million tons of steel tubes per year in several works. With this new welding tube plant, BSG leads the way for tube production in China and will be the first manufacturer of welded and stretch reduced tubes, the so-called ERW-HSR procedure in the Middle Kingdom. The particularity of the plant layout is the possibility to continuously weld and stretch reduce at one time in one step, i.e. the tube is in the welding line and in the Stretch Reducing Block at the same time. Hereby, the yield of the production plant will be considerably improved.

After completion, the new plant will produce up to 300.000 t/a high-quality welded tubes with excellent tolerances and perfect material properties. The range of products includes tubes within a diameter range of 60.3 to 177.8 mm with wall thicknesses of 4.83 to 13.72 mm according to international standards for applications in the oil and gas industry.

The 3-roll Stretch Reducing Block in "Star Drive" design, which will be used for the first time in a tube welding plant, will roll all finished sizes out of only one mother size of 193,7 mm diameter. The SRB will be designed for the use of up to 24 non-adjustable and adjustable stands with a nominal roll diameter of 360 mm. The last three stands used in the block are adjustable finishing stands, the other stands are non-adjustable reducing stands. The quick changing system for the stands and the roll shop with quick roll changing considerably reduce the required quantity of changing stands for an optimum production.

The Rotating Hot Saw type RHS 1000, which will be installed between SRB and cooling bed, allows the production of different tube lengths with tightest length tolerances. Thus, complicated batch conveyors and saws behind the cooling bed can be omitted and this reduces the investment and maintenance costs.

Furthermore, the following units belong to the scope of supply: roll shop equipment, electrical equipment, automation systems as well as Basic Engineering for local production which is obligatory in China, as, for example, gratings, roller conveyors, ejector and cooling bed. Supervision of assembly and commissioning, training of operators as well as the transmission of process know-how are also KOCKS' responsibility.

Commissioning of the new tube mill is planned for the second half of 2011.