Siemens Steam Turbines
Skip to Content
Siemens Steam Turbines
Economical dual-casing steam turbine for reheat applications
Siemens’ model SST-700 / 900 steam turbine is a standard turbine solution featuring a short delivery time thanks to its fixed standard design. Pre-defined turbine modules enable short manufacturing periods, cost-efficient materials supply and fast ex-works delivery. The straight-flow turbine design solution offering power outputs of up to 250 MW consists of one geared high-pressure (backpressure) steam turbine, and a combined intermediate/low-pressure (condensing) steam turbine, both of which drive an electrical generator arranged between them. The dual-casing reheat turbine configuration with inner casing is a competitive, optimized product for combined-cycle power plants and concentrated solar power plants.
Typical fields of application
The SST-700 / 900 is configured in Siemens’ global standard Enhanced Platform Design. The turbines are highly efficient thanks to the improved blade and seal designs. The steam path is equipped with specialized steam inlets which ensure high temperatures (up to 565 °C) with short heatup times, which likewise contributes to enhancing efficiency, as do additional competitive solutions for lower parameters. The turbines are all of simple modular construction for flexibility and ease of configuration and maintenance.
Fast load changes, short startup times
The optimized homogenous geometry of the casing design guarantees reduced startup times by up to 50% over previous designs. Faster load changes and an unlimited number of load
changes over the unit’s service lifetime allow for virtually any load regime.
Long service life
The consistent long-term material behavior of this turbine series ensures a long product service life of 200,000 operating hours. The use of proven designs for the high- and intermediate-pressure blades with tried-and-tested root clamping designs, for example, and of maintenance-free bolts good for up to 50,000 operating hours, serves to ensure a very high level of availability.
Reheat improves efficiency
Integrating a steam reheat system is one of the best means of increasing overall plant performance. In Siemens’ reheat turbine package, live steam is routed through a high-pressure (HP) turbine, returned to the steam generator to increase the steam temperature, then routed through a low-pressure (LP) turbine. Raising the temperature of steam that is moving from an HP turbine to an LP turbine generates higher output for same amount of fired fuel.
|Power output||up to 250 MW|
|Turbine speed||3,000 or 3,600 rpm|
|Live steam inlet pressure||≤ 180 bar(a) / ≤ 2611 psi|
|Live steam inlet temperature||≤ 565°C / ≤ 1050°F|
|Reheat||up to 565°C / 1050°F and up to 45 bar(a)|
|Condensing exhaust casing||up to 12.5 m²|
|Controlled and / or uncontrolled (up to 7) extraction possible|