In a condensing turbine, the exhaust in a vacuum goes to the condenser and it represents wasted energy. Whereas in a backpressure turbine, the exhaust from the steam turbine is used effectively in a downstream process. In certain changed situations, an existing Extraction Condensing Turbine may have to be changed to Back Pressure Turbine.
In conversation of condensing turbine to backpressure turbine, the challenge is to redesign the turbine internals within the casing boundary conditions. Turtle Turbines can convert the existing condensing turbine into a back pressure turbine with a new optimized steam flow path. By eliminating the last blade stages and implementing a new shaft sealing on low-pressure end to allow only cooling steam flow. The earlier extraction flow is reused and modified to become the new exhaust of the turbine. The turbine casing could be reused with minor modifications, minimizing the required investment and shutdown time as much as possible.
Turtle Turbines keep the same turbine casing, same layout, and foundation. The customer receives upgraded equipment that is able to deliver a significantly increased heating steam output which allows their customer to have a more profitable operation of the powerplant. Hence investment cost is minimized as new major equipment was eliminated and the upgrade was made possible without having to stop the equipment longer than usual and required major overhaul.