The operation efficiency analysis of HPC for K-300-240 turbine with over-bandage seals replacement at the Trypillia TPP.
Students Name: Semeniuk Olha
Qualification Level: magister
Speciality: Heat and Power Engineering
Institute: Institute of Power Engineering and Control Systems
Mode of Study: part
Academic Year: 2022-2023 н.р.
Language of Defence: ukrainian
Abstract: Semeniuk O. V., Rymar T. I. (supervisor). The operation efficiency analysis of HPC for K-300-240 turbine with over-bandage seals replacement at the Trypillia TPP. Master’s thesis. – Lviv Polytechnic National University, Lviv, 2022. Extended abstract Today, 43 condensing power units with a capacity of 200 MW with K-200-130 LMZ turbines and 42 power units with K-300-240 turbines of JSC "Turboatom" are in operation at Ukrainian TPPs. A significant part of the thermomechanical equipment of the TPP has produced normative and extended park resources. The power plants put into operation in the period from the end of the 50s to the beginning of the 90s of the last century were designed for a service life of 100,000 hours. In practice, it turned out that the individual resource of a significant part of the turbines exceeded the estimated one, the working hours of which are 170-230 thousand hours, and individual power units (power units № 1 and 2 of the Zmiyiv TPP) reached 300 thousand hours [1, 2]. Thus, the performance of many power units approached or exceeded the extended park resource. Highly efficient production of electrical energy, as well as the use of energy-saving technologies, are important aspects of increasing the competitiveness of energy complexes. Of course, a significant part of the losses falls on the level of consumption of energy resources. But, despite this, all the possibilities for saving energy at thermal power plants have not been exhausted. In particular, in the case of the generation of electrical energy by the traditional steam turbine method according to the Rankine method, a large reserve of savings lies in the area of improvement of the flow part of the turbine. It is known that the degree of its perfection is characterized by the internal relative efficiency [3, 4]. Analysis of the operation of many power plants, especially TPPs, shows that this indicator is not given enough attention. The internal relative efficiency takes into account the large amount of losses in the working process of an operating turbine compared to an ideal turbine operating without losses. Among all the losses, losses due to the flow of steam through the gaps are of particular importance and can be decisive for the efficiency of the turbine. The presence of technological gaps in the flow part of the turbine is necessary due to the prevention of engagement of the turbine rotor with the stator. One of the areas of work in the field of improving the thermomechanical and operational indicators of the operating steam turbine equipment is the modernization of the flow part with the use of improved structures of seals with a honeycomb surface. Only due to the reduction of the radial gaps in the case of the formation of honeycomb overbandage seals, the increase in the relative internal efficiency of the high-pressure cylinder is 0.6 - 1.7%. In this case, the maximum increase is achieved in the case of equipping all stages of the cylinder, including the regulating one. Study object – power units of 300 MW, improvement of the flow part of the K-300-240 turbine of Trypillia TPP using modern technologies. Scope of research – application of modern technologies for the modernization of steam turbine equipment of the Trypillia TPP. Goal of research: development of proposals for the modernization of steam turbine equipment using the example of the 300 MW power units of the Trypillia TPP, taking into account modern technologies and the study of the impact of some of these proposed solutions on increasing the efficiency of the flow part of the turbine. In the master’s qualification work, the economic effect of replacing the radial overbandage seals of the traditional high-pressure cylinder with cellular ones was determined at the same time (one-time). Reconstructions were provided with 10 stages of a high-pressure cylinder, excluding the regulating and the first non-regulating one. The operating time of the turbine before the overhaul was approximately 190,000 hours. In order to minimize the error of the final result, the research was carried out in two stages according to uniform technical programs and methods using the same measuring tools: the first stage – before major repairs with the installation of seals; the second stage – after major repairs with installed seals. In the master’s qualification work, the thermal tests of the K-300-240 type steam turbine after the reconstruction of the flow part of the HPC are given in order to improve the economic indicators of the HPC. The reconstruction of the flow part of the HPC included the replacement of superbandage seals of stages 3-12 with modernized honeycombs. In the "Economic part" section, the technical and economic indicators of the TPP were calculated before and after the reconstruction of the HPC of the K-300-240 turbine. In the automation section, a functional scheme for automating the regulation of the K-300-240 steam turbine has been developed. Keywords: over-bandage seals, turbine, high-pressure cylinder, flow part of the turbine. References 1. Boiko A. V., Usatii A. P., Rudenko A. S. (2014). Multi-criteria multi-parameter optimization of the flow part of axial turbines taking into account the operating modes: monogr. Kharkov: NTU «KhPI». 220 р. 2. Chernousenko, O.Yu., Peshko V.A. (2016). The influence of the operation of TPP power units in maneuverable mode on the depletion of the energy equipment resource. Visnyk NTU «KhPI». – Kharkiv: NTU «KhPI». – № 10 (1182). – РР. 6 – 16. 3. Chernousenko, O.Yu., Peshko V.A. (2016). The effect of the operation of TPP power units in maneuverable mode on the reliability and failure rate of power equipment. Visnyk NTU «KhPI». – Kharkiv: NTU «KhPI». – № 8 (1180). – РР. 100 – 160. 4. Chernousenko, O.Iu., Butovskyi, L.S., Hranovska, O.O., Peshko, V.A., Moroz, O.S. (2016). The influence of operation in maneuverable modes of TPP power units on technical and economic characteristics. Problemy zahalnoi enerhetyky. – Kyiv. In-t zahalnoi enerhetyky NANU. – № 2 (45). РР. 21 – 31.