This paper describes the FT8-2 Dry Low NOx (DLN) combustor development process and reviews the development history and initial field experience at a natural gas pipeline station in Germany. The development process is primarily focused on defining a fuel nozzle or injector, investigating emissions, fuel-air mixing, flame stability, acoustics, flashback resistance, and flame disgorgement. Empirical development tools including single nozzle and sector combustion rigs, as well as flame imaging techniques, are discussed. A summary of in-house engine development testing is provided. The control methodology used to meet emissions, while maintaining combustor pressure pulsations at an acceptable level, is provided. The natural gas compressor station design and operational experience with a GHH BORSIG compressor driven by the FT8 engine in Werne, Germany is summarized. Also presented are details of the very short conversion period from Standard to DLN combustor with the first successful ignition of the engine 26 days after work had begun.

In cooperation between Siemens and MAN GHH an industrial gas turbine with an ISO rating of 9.2 5 MW was equipped with a dry low NOx combustion system. Using the hybrid burners of Siemens gas turbines, a new combustion chamber was developed for the gas turbine THM 1304 of MAN GHH. This gas turbine has two V-like arranged combustion chambers, which allow a redesign of the combustion chamber, without changing the remaining parts of the gas turbine and its casing. So it is possible as well, to fit present machines with new combustion chambers. The combustion chambers contain flame tubes of Siemens technology with ceramic tiles and the well proved hybrid burners. After calculation and design the air flow was examined in an isothermal flow model. Finally two prototypes of the combustion chamber mounted on a THM 1304 gas turbine were tested at the MAN GHH gas turbine test bed. Success came very quickly and the test runs are finished now. So for the first time the transfer of the well-known low emission values of the Siemens large scale gas turbines succeeded to an industrial gas turbine of the 10 MW class.

This paper focuses on metallurgical issues and manufacturing of impellers for an integrally geared 2-stage expander for a corrosive hot-gas application. The design employs the largest single piece forging in Alloy 718 material for use in the low pressure stage impeller. Alloy 718 was chosen due to the combination of best corrosion resistance and mechanical properties. With this single piece forging it is possible to manufacture very large impellers in a "non-welddesign". Information about development of the disc production, the manufacturing process and mechanical properties are presented.