Prominvest Development has modernized the steam turbine PT-80/100-130/13. The main tasks were to increase the throughput of the medium pressure part, to modernize the steam distribution system of the medium-low pressure cylinder, and also to normalize the system of thermal expansion.
Thoughtput increase:
- Reconstruction of case of the medium-low pressure cylinder with the installation of a new guide vane;
- Installation of new diaphragms of 2-10th stages with sealing rings;
- Modernization (sealing) of the rotary diaphragm of the 11th stage of low pressure;
- Installation of new working blades of 1-10th stages with all-milled bandages;
- Replacement of the rotor of medium-low pressure;
- Installation of new clips of diaphragms No. 1, 2, 3;
- Modernization of control valves of medium pressure;
- Installing a new front seal cage and sealing rings;
- Installation of the upgraded rear end seal of medium-low pressure cylinder.
As a result: An increase in throughput to 302 t / h at a pressure in the production sampling of 13 kgf / cm2 and up to 380 t / h at a pressure in the production sampling of 16.7 kgf / cm2. The maximum steam flow into the condenser is 220 t / h.
Modernization of the steam distribution system
- Replacing low pressure regulating valves with valves of a larger bore diameter. Control valves are made of a discharged type without piston rings with the aim to reduce efforts. The use of a spline lock eliminates threaded connections in the valve cup and provides easy disassembly of the valve during repair;
- Replacement of working fists;
- Replacement of old cast iron columns with steel ones that do not have “growth” properties and have an unlimited service life;
- Replacement of cam-distributing device of medium-low pressure cylinder with new ones with metal-fluoroplastic bearings of increased reliability.
Normalization of the thermal expansion system:
- Revision and modernization of key connections of the high pressure cylinder;
- Inspection and bringing to design condition of support and suspension systems of pipelines connected to the high pressure cylinder;
- Measurement of the loads on the support legs of the high pressure cylinder using dynamometers (supplied by the Seller) during the assembly and operation of the turbine, measurement of thermal displacements of the elements of the turbine unit;
- Implementation of measures based on the results of the survey in order to optimize reference loads and improve the characteristics of thermal displacements of the turbine;
- Installation of metal-fluoroplastic coatings.
Reliability indicators:
- Turbine overhaul period — 6 years;
- The full assigned service life of new units (with the exception of wearing parts) — at least 40 years;
- The full assigned service life of the turbine parts left in operation is determined by the results of the survey;
- Warranty 24 months from the date of commissioning of the machine.
As a result, an increase in the nominal power up to 98 MW, the maximum — up to 110 MW with a fresh steam flow rate of 470 t / h.
After modernization, the turbine is marked as PT-98 / 110-130 / 13-1M.
