The coking plant Zentralkokerei Saar is a subsidiary of Dillinger Hütte GTS and with 5.000 employees, is one of the leading manufacturers of heavy plate whose steel plates are used for the construction of skyscrapers, bridges, wind energy plants, oil and gas pipelines. Furthermore, this company which was founded in 1685 is Germany’s oldest stock corporation. The subsidiary Zentralkokerei Saar has been operating three Two-Stage VRO Process Gas Compressors for the compression and conveyance of coke oven gas since 1982. The first stage is a VRO 736 L and the second stage is a VRO 536 S. The first stage has a conveying volume of 498 cubic metres per minute at 1,06 bar (a) intake pressure. The second stage compresses the coke oven gas to a final pressure of 12,7 bar (ü). The installed motor which is speed-controlled and provided with two shaft ends drives both compressor stages and has a power output of 4.300 kilowatts.

The inspection that has now become necessary after 40.000 operating hours was executed by two Aerzen Service Engineers in February and March 2009. The plant was successfully restarted still in March.