Condensing steam turbine for a steel plant

Objective of the master’s thesis is the thermodynamic design of condensing steam turbine for steelworks place on frame. Steam turbine can be operated with one controlled extraction point from 0t/h to 115 t/h at terminal power 60 MWe and speed of 3 000 per minute. The entered parameters are the admission states of steam at the inlet to the steam turbine, required properties of steam in the process extraction point and temperature of cooling water with flow in water cooled condenser. At the beginning of design of the steam turbine is thermal scheme, defining state of steam in significant places and predetermined mass flow through condensing steam turbine. The following is the design of two regulatory stages with equal pressure blades. First is for High pressure stepped section and the second is for low pressure stepped section. The solution of stepped section is divided into two chapters. The first deals with preliminary determination of the geometry and the number of stages, the second is main part of the whole thermodynamics design of a condensing steam turbine. Stepped section is solved with over pressure blading set on the drum rotor. The calculation is divided into low pressure stepped section for design mode with zero process extraction point and high pressure stepped section, which is designed for off taking mode. Steam turbine is consisted of 6 cones about 32 stages. Thermodynamics efficiency in off taking mode is 86,1 % and mass flow 71,94 kg/s, in condensing mode 83,4 %, respectively 53,01 kg/s. Part of design is strength check of blades, critical speed check and design of compensating piston with the system of labyrinth glands and bearings. Thesis is supplemented by operating characteristics and longitudinal section of condensing steam turbine