Dietmar A. Wolf: The lords of the rings

Siegthaler_Moll_175-kopierenThe high-quality production and processing of steel in North Rhine-Westphalia has an excellent reputation. As the Wolf Group in the Siegerland exemplifies, increasing requirements demand a high degree of flexibility and specialising from the manufacturing industry.

The 54-metre-high shell construction is already finished: one of the biggest ship canal lifts in Europe is currently being erected in Niederfinow in Brandenburg along the Oder-Havel Canal. In the future, up to 115-metre-long and 11.45-metre-wide ships will enter the trough of the ship canal lift. Four machines with a total output of 1,280 kilowatts will heave about 10,000 tonnes – held by steel ropes which run safely over 112 double pulleys.

The Wolf Group, which comprises the companies Robert Josef Wolf, the Siegerthalerfabrik as well as Landruf Rohrtechnik manufacturers these pulleys in the Sie­­gerland. The steel starts to glow in the company’s halls when it is bent and welded into metre-high rings. 224 of them are joined to create 112 double pulleys, which will in future lift and lower the ships in Niederfinow. “This project is of utmost importance for us. And that not only because of the volume of several million euros,” says Dietmar Wolf, who together with his brother Klaus-Dieter manages the businesses of the family-owned company in the second generation. After all, all three firms of the Group are involved in the project at five production locations in the Siegerland. The Wolf Group is specialised in everything that is big, heavy and made of steel and that requires being manufactured with extreme precision. This includes, among other things, tanks and containers for chemical companies, power plants and the beverage industry as well as flanges for mechanical engineering and wind turbines. For that, the ring forge in Wilnsdorf, located in the “Lehnscheid VI” industrial area, has a com­­prehensive range of equipment such as rod heating, ring bending machines, welding machines, annealing furnaces and cooling plates. Furthermore, at this location exists one of the largest polymer quenching basins for tempering in Germany, with a volume of 400 cubic meters, 40 tonnes and a maximum charging space measuring 7 x 7 x 2 metres. The respective machines for the mechanical processing (vertical turret lathes up to 8,000 mm in diameter, drilling machines and milling machines) also belong to the Group’s portfolio.

The company is ready to take on everything involving mechanical processing. That is why, components from 300 millimetres to eight metres in diameter and 10,000 x 4,500 millimetres respectively can be machined by lathing, drilling and milling them, tube sheets up to 4.5 metres. Our crane capacities are able to move welded constructions weighing up to 50 tonnes. All common materials in the areas of EN and ASME standards, and in fact not as standard components, can be handled in the material processing. Above that, non-ferrous metals and cast irons are processed. The Group in the Siegerland is positioning itself as a system supplier for example for mechanically processed welded constructions and possesses all the necessary approvals from the certifying authorities.

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Robert Josef Wolf GmbH & Co. KG is a family-owned company with more than 60 years of experience in tank and apparatus construction, which is managed with all the benefits a medium-sized company structure offers. The focus of production is on pressure vessels, heat exchangers, columns and special constructions. The com­­pany manufactures components with a diameter up to 5.5 metres, a maximum workpiece length of 50 metres and a workpiece weight of 100 tonnes at two different locations. Construction steel, fine-grained steel, creep resistant as well as low and high-alloy steels are processed. Tremendous importance is put on service and quality.

Landruf Rohrtechnik GmbH was founded with the current corporate name in 1997. Employees with many years of experience in the areas burning, forming and welding quickly turned Landruf Rohrtechnik GmbH into a specialist in the production of cylindrical and thick-walled pipes. The machinery and comprehensive know-how of the operators ensures that the products can be produced with narrow tolerances. In 2013, the company relocated to its new location in Siegen-Weidenau. In the course of the relocation, the four-roll bending machine was completely overhauled and new sub-arc welding machines with 3-wire technology were installed. In the production of shells, cylinders and large-diameter tubes, workpiece weights of approx. 70 tonnes and lengths up to approx. 36 metres are possible in the assembly by circular welding. Also, helical and circular welding for a dimension range of 600 to 4,500 milimetres diameter is possible.

IMG_0418-kopierenDietmar A. Wolf
Mr. Wolf (born in 1960) studied mechanical engineering at the RWTH Aachen. From 1987 to 1993, he worked in different positions at Mauser-Werke GmbH in Brühl and Bammental. At the end of 1993, he joined the family enterprise Wolf Behälter- und Apparatebau. In 1999, he took over the management of Siegthalerfabrik GmbH. Together with his brother, Klaus-Dieter Wolf, he heads the companies in the Wolf Group as managing partner.