With the deepening of reform and opening up and the further reform of the domestic power system, various power companies have become more and more interested in investing in domestic thermal power projects. At the same time, they have begun to look beyond the domestic market; after some well-known domestic trade The company's long-term efforts have built and tracked a number of thermal power plant projects in the form of EPC in South Asia, Southeast Asia, and the Middle East, and are actively developing markets in Africa, South America and North America.
In addition, with the development of the domestic power industry and the continuous efforts of power equipment manufacturing companies, the performance of domestic power generation equipment has been continuously improved and has approached the level of Western developed countries, making the export of domestic large-scale power equipment possible and making great achievements.
1 Distribution and Scale of Foreign Thermal Power Projects* Foreign thermal power projects were previously mainly distributed in South Asia, Southeast Asia, and the Middle East. Recently, they are actively developing markets in Africa, South America, and North America. The most recent countries with more information are India and Indonesia. One characteristic beyond the imagination of most people is that the market in North America, that of the United States and Canada, is also very promising. The reason is that not all owners are able to afford SL, BVI, and GE, SIEMENS products, in terms of equipment quality. Under acceptable circumstances, the quotation from the Chinese contractor has great attraction for the medium-sized local companies. If the development is good, this market will be very large.
At present, the maximum capacity of China’s export units is 300MW (Muzha Fat IX320MW, Arak 4X325MW, Sahand 2x 325MW), and the maximum capacity of the project being tracked is 600MW (subcritical), with China’s supercritical 600MW units It is possible that the introduction of manufacturing technology and its digestion and absorption will drive it into the international market.
It is regrettable that so far there has been no 60Hz frequency cycle of large-scale power equipment export performance.
2 Feasibility analysis of mainframe manufacturing The equipment manufactured by mainframe manufacturing companies in China is basically used for 50Hz cycle, and only a few mainframe manufacturing companies manufactured for exports in the 1970s and 1980s, and the maximum 50MW that is suitable for 60Hz cycles. The crew. For the current large-scale units, host manufacturing companies in various countries have not made technical reserves, but they all claim to have design and manufacturing capabilities.
2.1 Steam turbines After decades of independent development and technology introduction, major steam turbine manufacturing companies in China have fully mastered the development, design, manufacture, and testing of 50-Hz frequency-cycle steam turbines. They have supercritical, subcritical, and other differences in the manufacture of maximum 600MW capacity. Power levels, various forms of condensing, back pressure, heating, industrial extraction, and intermediate reheat turbines. These technologies are based on contemporary computer technology and involve various fields including high-speed pneumatics, engineering thermodynamics, heat transfer, strength, vibration, materials, computer automation, precision machining, and engineering structural design optimization. These include complete turbine design calculations. Library, product design manuals, guidelines and specifications, materials, processes, quality assurance, standards, and development studies design reports. Its products' economy, reliability and operational flexibility have reached or approached the world's advanced level. The production performance of major domestic turbine manufacturers has reached a total power of about 50,000 MW.
So these companies are fully capable of developing large-capacity steam turbines that produce 60Hz cycles.
Taking a backbone steam turbine manufacturing enterprise as an example, when the company introduced foreign steam turbine technology in the 1980s, it redesigned the turbine with the same capacity of 60Hz cycle as a 50Hz cycle turbine, roughly 1.2 times that of the original equipment. The original drawings will be a good reference for turbines that produce 60Hz cycles.
In addition, after a joint venture with a foreign company, the company introduced a series of drawings and data of 40 different power grade turbine block blocks with a large number of operational performance. These block blocks can be combined into various types of 50-Hz and 130-1300MW thermal and nuclear steam turbines. Group; complete set of drawings for typical high-power subcritical and supercritical steam turbines.
The building block design technology of modern steam turbines is to develop a series of block blocks with turbine cylinder as a unit within a certain range of power and parameters. According to the market demand, through the combination of building blocks to match a variety of different power turbine units, which is characterized by a given power, parameter range, most of the components of the building block are common, such as cylinders, valves, bearings , auxiliary systems, control systems, pipelines, and foundations. This versatility not only shortens the design, manufacturing duration, and reduces costs, but also the application experience of the building blocks in different units can be accumulated, thereby fully guaranteeing the one-time success rate of designing the unit according to the user's requirements; the building blocks (cylinders) are connected The flow part can be according to the user's requirements. Not only the number of stages, the height of the blade, and the width of the crucible can vary with the power change, but also the advanced pneumatic technology can be used to optimize the flow section and update the airfoil shape, such as using a controllable vortex. Saber type, etc.; it is also possible to continuously optimize the structure of the through flow section, such as self-contained shrouds, damped rotors, reinforced blade roots, and triple rotor blades, to improve the economy and safety of the unit. Foreign companies have considered the versatility of 50Hz and 60Hz when designing high and medium pressure cylinder blocks, that is, the critical speed of the rotor has been considered to avoid 3000r/min and 3600r/min, and has taken into account the strength at different speeds Claim. Therefore, for a 60 Hz unit, the high and medium pressure cylinders are the same as 50 Hz, and only the flow passage optimization procedure is needed to re-optimize the flow passage portion; the introduction of 60HZ low pressure cylinder blocks of different grades has an exhaust area of ​​4. 710 mm, respectively. 816.4mm, l016 and 1050mm; the maximum steam extraction capacity is designed for safety at 73t/h per square meter and can meet the needs of various capacity units.
Most of the kits are the same, only two of them need to be changed, that is, the DEH software is slightly modified, and the speed loop needs to be reset; the critical breaker needs to be redesigned. After the company’s joint venture, turbine equipment was restricted when it was exported to individual countries.
2.2 Like turbine and steam turbine manufacturing companies, after decades of independent development and technology introduction, major domestic turbine generator manufacturing companies have fully mastered the development, design, manufacture and test technology of 50Hz frequency-controlled steam turbines. Maximum 600MW capacity and other different power levels, various cooling turbine generators. The economic, reliability and operational flexibility of its products have also reached or approached the world's advanced level. Therefore, these companies are also fully capable of developing large-capacity turbine generators that produce 60Hz cycles.
Its rated active power and rated voltage should be reduced to 5/6 of the original value; for example, 60Hz frequency turbine generator, 300MW capacity, 24kV terminal voltage, if used for 50Hz frequency, it can only press 250MW capacity, 20kV terminal voltage The use of generators, but also to account for the temperature rise of various components, and take appropriate measures. Because of the high rotational speed of the 60Hz frequency turbine generator, under the same conditions, the generator air volume is 20% higher than the 50Hz frequency turbine generator; the ventilation condition is better than the 50Hz frequency, but the mechanical stress is also higher than the 50Hz frequency. In general, the 60Hz cycle and the 50Hz cycle generator have the same stator, but the rotor is different.
Taking a backbone steam turbine generator manufacturing company as an example, after a joint venture with a foreign company, the company has introduced a series of drawings and data of turbine generator block blocks of different power levels with a large number of operating performance. These block blocks have a 50Hz cycle frequency. Both frequency and 60Hz frequency can meet the needs of different users.
Foreign companies always design a 60Hz high-frequency turbogenerator with excellent performance, and then modify the rotor according to the needs of users, and derive a 50Hz turbo generator.
2.3 The boiler boiler itself is not affected by the 60Hz cycle, but it should be noted that if the CFB boiler is used, the export permit is a big problem.
3 Feasibility Analysis of Auxiliary Machinery Manufacturing 3.1 Motors The technical level of major domestic motor manufacturing companies has been greatly improved. Individual companies have also introduced a full set of technologies (including electromagnetic calculation programs) from foreign companies, which can be based on the load conditions provided by users. , Design and production of various capacity grade 60Hz motors.
The domestic electric motor manufacturing enterprises already have the performance of manufacturing 60Hz electric motors and exporting in batches. The power level ranges from 10kW to hundreds of kW, and the voltage level ranges from 380 to 2300V. 3.2 Fans Domestic fan manufacturers have followed the Soviet Union from the 1950s to 60 From its own design until the end of the 1970s, the introduction of technology from Western countries and the promotion of the development of enterprise technology have made the economic indicators and reliability indicators of wind turbines, one of the main auxiliary engines of thermal power plants, reach the world level.
Domestic wind turbine manufacturers have introduced wind turbine manufacturing technologies from foreign companies such as TLT, KKK, MHI, NOVENCO, and HOWDEN from the end of the 1970s. The introduction of these technologies has enabled these companies to provide different capacity for different capacity domestic units. Pressure fan.
For fans with different flow rates and pressure heads, different speeds are usually used to achieve high efficiency or high pressure heads. For a 60Hz fan with a frequency of 篼1.2 times that of a 50Hz fan, and a rotational speed that is 1.2 times higher, the strength calculation and the critical rpm of the peripheral speed of the impeller can be used to ensure the safe operation of the equipment.
Domestic wind turbine manufacturing companies already have the performance of manufacturing and exporting 60Hz fans, and the supporting host capacity is 660MW. 3.3 Pumps Domestic pump manufacturers have the same development experience as domestic wind turbine manufacturers, and have also introduced KSB, SULZER, and WEIR one after another. The company's technology is used to manufacture boiler feed pumps, condensate pumps, and circulating water pumps that are used on different capacity hosts.
Domestic water pump manufacturers have the ability to provide 60Hz pumps according to the requirements of users.
4 Feasibility analysis of instrument and control part In the thermal control equipment, some of them need to be imported, such as DCS, various analytical instruments, important safety valves, etc. For these devices, as long as ordering is 60Hz, foreign manufacturers will produce according to requirements. It is forbidden to make any changes; For domestically-made imported products, such as the implementing agencies, transmissions, etc. as long as the order can be explained; for domestic products, only need to be stated when ordering, the manufacturer can make a small amount of changes in the power supply; Small motors, in general, 50Hz devices also apply 60Hz, no change. 5 Problems of patents and intellectual property rights During the tracking, bidding and implementation of foreign thermal power projects, patents and intellectual property rights are often encountered. In the past, the equipment supplied by the host equipment manufacturing enterprises in China was installed in the country, and some of the units exported were We have not opened up to a large extent and we have not introduced many technologies. Therefore, the issues concerning patents and intellectual property rights are not outstanding. In recent years, with the introduction of a number of patented technologies, the manufacturing capacity and technical level of domestic host manufacturing companies have made considerable progress, and they have also achieved remarkable results in the domestic power market. However, they encountered both when tracking and bidding foreign thermal power projects. The problem with patents and intellectual property rights is that these host manufacturing companies often restrict the sales area of ​​products when they purchase foreign patents or set up joint ventures. Equipment is limited when exporting to individual countries and must be considered before tracking foreign projects. The location of the project will be selected.
When it comes to patents and intellectual property rights in technology transfer, it must have sufficient strategic vision and actively develop its own proprietary technology.
6 Conclusion Although the equipment manufactured by the host manufacturing company is basically used for 50Hz cycle, in recent years, with the continuous development of technology and technology introduction, a complete technical system has been established, combined with individual companies to introduce the original 60Hz frequency block Block, so fully capable of producing large-capacity 60Hz cycle power generation equipment.
Each subsidiary machine manufacturing company also has the ability to produce auxiliary 60Hz auxiliary machines, and individual companies already have the performance to produce 60Hz frequency auxiliary equipment.
The design work can be completed. Individual domestic mainframe manufacturing companies have manufacturing drawings for 60Hz frequency masters, which may be shorter in the design cycle. In view of the lack of demand, domestic host manufacturing companies have not invested in the processing technology, equipment preparation, etc., but the manufacturing cycle is similar to that of the 50Hz frequency cycle host. It is only possible that the newly manufactured 60Hz cycle unit has the same cost as the 50Hz cycle unit. Certain differences. :2003-07-04 He Northwest Electric Power Technology 4/2003
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