Steam turbines do not only take the primary position in the orders portfolio for OJSC “Power Machines”, but they also are the most widespread pieces of equipment installed for use in thermal and nuclear power stations worldwide – they account for about 80% of all produced energy.
Russian turbine manufacturers have been amongst the world’s leaders for decades, creating reliable and efficient equipment. A lot of this is down to a key subdivision of Power Machines – SCB (Special Construction Bureau) “Turbina” at the Leningradsky Metallichesky Zavod (LMZ), which celebrates its 105th anniversary this year.
Today, SCB operates in three basic fields: NPP turbines, TPP turbines and the modernization and upgrading of steam turbine equipment for existing power plants. The development of 1200 MW high-speed and low-speed turbines for nuclear power plants is a current focus, and the related operations are underway and on schedule.
The detailed design for the high-speed turbines has been completed, with the prototype being manufactured for the Novovoronezh NPP-2. Turbines such as these have not been manufactured at the LMZ before. The K-1200 steam turbine used in thermal power stations was manufactured for the Kostroma SDPP in November 1977; since then, new technological advancements have been developed as well as new and improved materials which were used for the Novovoronezh turbine, which was contracted even before the detailed design had been completed.
Next on the production line are the1200 MW high-speed turbines for the Leningrad NPP-2. The detailed design for the low-speed turbines is scheduled for completion in 2013. Production of the low-speed turbine prototypes will take place at “Metallostroy”, our new production facility. The design of the entire turbine plant will be coordinated for a specific power station, with the general design contractor.
Designers at SCB work with the aim of increasing the capacity of high and low speed turbines from 1200 to 1600 MW, and there is no doubt these machines will be in demand, with power units with this capacity are currently being made in Finland and France. It should be noted that the Power Machines high-speed turbines have a number of very important competitive benefits when compared with other NPP turbine producers, namely lighter weight, smaller dimensions and correspondingly, lower construction costs.
Looking at turbines for ultra critical steam parameters, this project has a complicated history. The idea itself is not new and Russia was at the forefront of its development. At some point in the past, a 100 MW capacity SKR-100 turbine was produced by Kharkov plant and installed at Kashira SDPP. Its operating temperature reached 650°C with a steam pressure of 300 atm. Similar designs for 200-500 MW turbines have been in development at the LMZ since the early 1960s. Due to perestroika however, works in this area were suspended – it was no time for science or new designs during this period. The Company’s order books were not looking great and in order to survive companies were following other avenues. We are now making up for lost time however.
There are a number of options as to how this area can be developed. The best option would be to create a turbine for 700-720°С, which would help gain an immediate competitive advantage by making an unparalleled technical advance. The difficulties faced however include the expense of developing not only the turbine, but the related boiler and ancillary equipment, mastering new metals, higher operating costs. Other European manufacturers have worked closely with Governments on the financing and development of such projects, and therefore creating such a prototype should be seen as a challenge to be undertaken on the national level. As for being in demand, creating such turbine is a goal for the future.
The second option is to create a machine for 570-580 degrees bracket. In this case any large R&D costs could be avoided, because there are already existing developments available. Today however, it is more practical to develop a turbine with industry leading operating parameters and that is what the 660 MW turbine project (to be completed in 2012) is meant to achieve.
Two more new products should also be mentioned among thermal plant turbines – the K-280 and the K-130, which are designed for combined cycle gas plants with 800 and 450 MW capacity, respectively. The detailed design for K-280 will be completed next year, and K-130 design is due to be finished this year. Apart from this, the SCB is carrying out some large-scale works related to design of equipment for the construction of a new thermal plant, as well as full or partial modernization of turbines for existing power plants.
To mention a few projects completed over the last few years, we should note the K-225 steam turbines built for the Cherepets SDPP and the 3rd generating unit at Kharanor SDPP (operated by OGK-3)
The unique point about K-225 steam turbine is that this prototype was made using brand new technology. The K-225 will replace existing machines of average capacity which are currently used at many thermal stations both in Russia and abroad.
A particular aspect of K-225 project was the implementation of new technical solutions from the construction bureau at Power Machines for the power units under construction. During the design of the 225 MW steam turbine, a new type of high pressure cylinder blading was used for the first time in Russian power plant engineering. This new technology will vastly increaset the efficiciency of the turbine. In the past this type of blading was only used for more powerful turbines (e.g 300MW) at the Konakovo SDPP, the Konasima thermal plant in India and the Wong Bi thermal station in Vietnam.
To improve operational efficiency, the rotors of K-225 turbine were made of heatproof high-chromium steel and the rotor journals were protected with a surface coating made of from special alloy. These operations were carried out using technology developed by the NPP institute, at Power Machines’s automated welding center, which was commissioned in April 2010. Its creation involved the participation of specialists from LMZ and leading European companies including Fronius (Austria), Kistler (Germany) and Heatmasters (Finland).
The company management also made the decision to restore the full-scale testing unit at the TPP-17,Vyborgskaya. There are a number of processes that can’t be reproduced in laboratory conditions or when operating on scaled equipment such as the self-oscillation of blades, heating of the air-gas channels at low-feed operation, influence of steam humidity on the performance efficiency etc. All these occurrences, as well as aerodynamic properties and performance efficiency of the channel section, must be studied in a full-scale testing unit.
Because of this full-scale testing, unique results were obtained during the trials of 960mm x 1000 mm steel exhaust blades and 1200 mm long titanium blades, which were tested on turbines with a capacity from 200 to 1200 MW. Unfortunately, in the 1990s the testing unit was suspended, thus the recent decision to restore the testing unit is a very important step which includes us in the higher echelons of worldwide manufacturers. The design engineers will be able to test the channeling parts and blades for prospective high-speed and low-speed turbines with a capacity from 1500-1800 MW. Right now the TPP is undergoing some disassembling works, while the LMZ workshops are already producing assembling parts and components for the testing unit. Its launch is expected at the end of this year.
As is already known, the Power Machines management made the important decision to reinforce all engineering divisions of the company, which was later supported by a range of related activities. As a result of this, two more departments were created at SCB Turbina, the modernization and NPP departments. Expanding the modernization works has to do with the fact that over 60% of the TP turbines have already passed their recommended operational life, and an increase in implementation of NP units through to 2030 has been proposed by a Resolution of the Russian Government.
Today, the personnel of SCB Turbina, the largest of all engineering divisions of the company is much younger: almost a third of all employees are young graduates below 30. On one hand, this proves that the construction bureau has a bright future, on the other – that the workload for more experienced employees is increasing: there is a lot of mentoring work to be done to save and develop the Russian power plant engineering base.
Today SCB Turbina has the potential necessary to meet the challenges it is facing and there is no doubt that its highly qualified specialists are capable of reaching the goals that have been set.
