Design and development of large-scale axially-flowing hydro-generator unit Han Min, Luo Zhonghua (Sichuan Dongfeng Motor Factory Co., Ltd., Sichuan Leshan 614802 (Design concept and structural characteristics of large-scale shaft-through tubular hydro-generator units). 1 part of the power station and model power station name platform water introduction Large-scale shaft-through tubular hydro-generator unit is a simple structure, excellent performance, easy installation and maintenance developed by Dongfeng Motor Co., Ltd. It is suitable for low The installation of water head and large-flow power station generally uses a unit with a water head of 2.5~18m, a diameter grade of 1"3m and a rated output of a single machine"==5MW. The generator of the model moves out of the bulb body and is exposed outside the turbine. Various types of speed increasing devices are adopted. Due to the use of conventional generators, small and medium-sized units are economically significant. In the development of small and medium-sized hydraulic resources, the axial through-flow is less expensive than the bulb cross-flow, and the economy is good. It is convenient to use, repair and maintain than the bulb, and it is close to the bulb flow machine in terms of performance. The following table lists some of the models and codes that Dongfeng Motor Corporation has put into operation.
The overall arrangement of the shaft and the cross-flow turbine group, the water flow is introduced from the inlet pipe, and is discharged to the tail water channel through the water guiding mechanism, the runner and the draft tube. The elbow behind the runner chamber is s-shaped, and the turbine main shaft passes horizontally through the elbow and is connected to the conventional generator through a speed increaser. The hydro-generator set has 2 guides and 1 push for a total of 3 bearings, of which 2 bearings are provided on the turbine side. The turbine radial bearing is arranged in a fixed support, the radial thrust bearing is arranged on the floor of the factory between the elbow seal seat and the speed increaser; the radial bearing of the generator is arranged on the downstream side of the rotor. The generator and turbine bearings share a fuel supply system for centralized oil supply. In order to ensure the stable operation of the unit, the bottom of the generator pit has a sufficient distance from the flow path.
The shaft-through-flow turbine is horizontally arranged, without a volute, and the flow passage is also axial. The water flow is parallel to the turbine shaft to the runner, and the water guiding mechanism can be arranged close to the runner blade, thereby fully Control the water flow conditions at the entrance of the runner to make the runner more resistant to cavitation. The water guiding mechanism adopts a conical arrangement, 16 guide vanes are arranged in a conical shape between the inner and outer water distribution rings, and the taper angle is 65. Considering the stability of the operation of the unit, most of the seat ring and the draft tube of the inlet pipe are buried in the concrete. A square hole is formed in the top of the turbine inlet pipe for use in loading and unloading the workpiece inside the bulb. There are four fixed pillars for the turbine part in the flow channel, wherein the upper pillar is the inlet of the oil, gas and water pipelines, the lower pillar is the outlet of the drain pipe and the drain pipe, and the weight of the components in the runner flow passage and the dynamic load are fixed. The pillars are passed on to the foundation. The governor is arranged separately from the hydraulic device, and is disposed on the upstream side of the water turbine, and is connected to the water guiding mechanism of the water turbine by operating the oil pipe and the feedback wire rope. The bearing high-position fuel tank is arranged in the auxiliary building of 8~10m from the center line of the unit, and the hydraulic station of the return tank and the speed increaser is arranged in the turbine pit. The overall layout is shown in the figure.
Main structural characteristics of the turbine 3.1 The selection of the runner and the spindle shaft through the turbine is different from that of the bulb. For example, the cascade density is 1/! The size of the value is an important factor affecting the unit speed and unit flow. Choose a smaller 1/!
The value of the runner has a large overcurrent capability and a high unit speed. However, the draft tube restricts excessive flow through, due to 1/! If the value is too small, the water flow energy conversion is insufficient to cause the hydraulic efficiency to decrease. Therefore, the shaft-running turbine runner adopts a smaller 1/! Value, and take a larger 1/! near the hub! The value, the average density of the blades is also large, and the edges of the leaves are curved. In addition, the relative torsion angle of the blade is slightly smaller than that of the bulb runner, so that the runner designed with the selected parameters has excellent energy and cavitation characteristics.
For a rotary shaft type through-flow turbine, the rotating mechanism of the runner is a straight link mechanism with an operating frame. The blade recovery mechanism is disposed on the oil receiver, and the mechanical motion is output through the sector plate and the wire rope.
The runner blade is sealed with multiple layers of “rubber. For the convenience of the runner installation, the runner drain cone is divided into upper and lower parts. The propeller type shaft-through tubular turbine is supported in the same way as the fixed paddle, both of which are two points. Support. Due to the large spindle length and span, in order to increase the spindle stiffness and reduce the weight of the spindle, the spindle adopts hollow forgings or thick-walled seamless steel tubes and welded flange structures. According to the characteristics of the shaft-through tubular turbine, its support position The diameter of the main shaft and the size of the inner bore should be determined by a plurality of schemes.
The shaft-through tubular turbine has a complicated structure and low generator speed. Compared with small units, it has large size and heavy weight, so it is required that the generator does not move when the turbine is disassembled. For this reason, it is convenient to disassemble and maintain the turbine or generator separately by providing a split-half transition flange between the two shafts.
The main shaft of the shaft-through tubular turbine is characterized by the installation of its main shaft and runner. Most of the shaft-through turbines are pulled out from the elbow shaft, which increases the width of the plant and moves the speed increases, thrust bearings, generators, etc. There are also runners, straight cones, and elbows that are horizontally separated by the axis. This solves the problem of hoisting the spindle, but increases the installation trouble of the casing and improves the manufacturing cost of the unit. Therefore, the runner chamber and the straight taper tube are divided into half, and the telescopic joint is disposed between the straight taper tube and the elbow tube. The semi-transition flange is arranged between the main shaft of the turbine and the main shaft of the generator. When the revolver and the main shaft are disassembled, the disassembly purpose can be achieved without moving other parts. The main shaft and the revolver can be directly divided into semi-rotary chambers and semi-straight. Lifting at the cone.
The guide vane of the water guiding mechanism adopts integral cast steel and two-point structure. The vane airfoil is a space-distorted line, and the upper and lower bearings are all self-lubricating bearings. The guide vane head seal can be protected by hot-sleeve stainless steel or chrome-plated to prevent corrosion from affecting the performance of the seal. In order to facilitate the installation, the short axis of the guide vane is arranged on the inner ring of the vane, and cooperates with the inner ring hole of the guide vane. The guide vane seal adopts the “type addition seal. The guide vane shaft and the guide vane arm adopt the cylindrical pin to transfer the torque by the half key. The adjustment of the upper and lower end faces of the guide vane is realized by the bolt of the guide vane end and the thickness of the adjusting collar. In the closed state, the total gap of the end face is 0.81.8mm, and the partial gap of the façade is less than 0.15mm in the height of the 1/4 guide vane. This requirement can ensure the leakage of small amount and ensure the flexible operation of the mechanism. The guide vanes are respectively equipped with a shear pin and a shear pin annunciator. When there is a foreign object between the vanes, the shear pin is sheared and signals to protect other parts from damage. Since the water guiding mechanism of the tubular unit is tapered, The operation of the connecting plate is a three-dimensional movement of the space. The shearing pin has a complicated force, shearing force, and a certain torque, which is easy to be cut. Therefore, the design of the connecting plate and the shear pin is a key point.
The vane façade is metal-sealed, and the tail and tail can be welded to the stainless steel as needed. The metal seal is used as the facade seal, the structure is simple and convenient, and the processing can completely ensure the tightness of the seal. At the same time, the cross-flow unit has low head and small leakage, and the metal seal form also facilitates the installation and adjustment of the water guide mechanism.
With the application of new materials, the anti-corrosion and wear-resistant composite sealing materials on the vane sealing surface are also increasing, which has a good development prospect.
The outer ring of the guide vane is evenly arranged with 16 lap holes obliquely for mounting the upper fulcrum of the guide vane. The outer ring of the guide vane is a thin-shell welded piece with poor rigidity. In order to increase the overall rigidity of the water guiding mechanism, it is necessary to appropriately arrange the circumferential or longitudinal ribs in the structural design. However, in order to solve the troubles caused by the deformation of the overall lifting, it is more important to design a dedicated overall lifting and turning positioning support tool.
The control ring is a rolling friction ring bearing structure. A steel ball is arranged on the sliding surface of the control ring, and a nylon spacer ball column is arranged between the steel balls, which can reduce the friction between the steel balls, and the control ring has a small friction torque, thereby ensuring flexible operation of the control ring.
The water guiding mechanism is provided with a control pendulum type relay. The large ring of the control ring is connected to the push rod of the servomotor, and the small hole is hinged to the fork of the guide vane. In addition, the control ring is also provided with a circular groove for the recovery wire. When the control ring makes a circular reciprocating motion under the action of the servo, the connecting plate is driven, and the connecting plate transmits the operating force to the vane arm hinged thereto, thereby realizing the control of the vane. In addition, on the basis of the motion and mechanical analysis of the transmission of the space water guiding mechanism, the control ring adopts the structure of single ear hole and single vane relay. The system has compact structure, clear arrangement and convenient installation and debugging. When the unit is shut down, the water guiding mechanism needs to be locked, and this function is realized by the servo. The lock spindle has two aspects, that is, the lock cylinder of the control oil pipeline and the hard lock spindle of the servo pusher pull rod from the mechanism. There is no automatic lock ingot when the servo is designed. Only the manual lock is provided in the fully closed position of the guide vane. This is a very reliable protective measure. Inside the bearing, the bearing is equipped with a bearing gland and a sealing copper piece. The bearing gland is equipped with an oil cup, and the lubricating oil is periodically filled to ensure flexible movement of the connecting arm. The use of the joint bearing makes the connecting ball hinge have a certain self-aligning effect, which can compensate the deviation of the water guiding mechanism during the manufacturing and installation process.
When the site is installed, the water guiding mechanism should be hoisted as a whole. Before the overall lifting, the guide vanes should be placed in the fully closed position, and then the adjacent two vanes are lap welded to each other by the ribs, so that the 16 vanes form an integral support ring with sufficient rigidity.
The main shaft seals the main shaft seals for a total of 3 lanes. The first lane is a comb-tooth seal, the second lane is a hydraulic piston-type working seal, and the third lane is an inspection seal.
The comb-tooth seal mainly acts to reduce pressure and prevent large particles of impurities from entering, and protects the second seal from the protective effect. To reduce wear, the comb seal is made of stainless steel.
The working seal is made of hydraulic piston seal, and the seal ring is made of medium-hard rubber with good performance. Features: It can store lubricating water, which is beneficial to the lubrication of the contact surface. The grooved water storage ensures that the water-passing hole will not be blocked by wear; the water-filled hole of the proper size is arranged on the sealing piston, so that the upper cavity and the inner cavity of the piston form an appropriate amount. Pressure difference; long life, easy installation, adjustment and maintenance. In design and processing, the amount of water leakage is controlled, and the size of the groove, the guide hole and the inlet hole should be strictly controlled. For multi-sand hydropower stations, the use of piston-type end face rubber seals should be noted that the seal water pressure must be greater than the leak pressure. In order to ensure the free movement of the piston, there should be a 0.05 mm gap between the piston and the piston body during installation.
The shutdown inspection seals are sealed with packing seals or air shrouds depending on the size of the unit. When the packing is sealed, the filler is a braided woven polytetrafluoroethylene impregnated carbon fiber filler, which is made of a plurality of carbon fiber filaments in a herringbone shape, and has a square cross section. Its characteristics are: soft, easy to impregnate the lubricant, floating elastic to the vibration and eccentricity of the shaft, and good compactness, which can meet the performance requirements of the main shaft seal on the packing. At the same time, the roughness of the shaft is high, so the friction loss is small. Generally, the roughness of the sealing surface should be higher than 3.2 pm. The surface of the shaft has sufficient hardness and can maintain the roughness for a long time. Or surfacing stainless steel can meet this requirement. The air shroud is used. When the unit is normal, the compressed air is not in the free state, and there is a gap of 1.52. 0mm with the cylindrical surface of the small shaft. When the machine is stopped, the surrounding air is filled with 0.50.7MPa compressed air, and the expansion is small. The shaft sealing surface acts as a seal. The air shroud is only used when the unit is shut down, so the requirements for the shaft are lower.
19 slab ball joints use standard joint bearings. To prevent dust from slamming (and by centrifugal force into the tail water hood / internal gravity, the bookmark2 spindle seal is to control the amount of water leakage instead of absolutely sealing water. In order to ensure the safety and reliability of the seal, the leaked water must be effectively treated. Therefore, after the sealing position is repaired, a water-repellent ring is arranged in the rotating part during design, and a water collecting pipe is arranged on the tail water cover, and the water-sealing ring discharges the leaked water seal through the water collecting pipe on the tail water cover. Effectively prevent the leakage of the main shaft seal from entering the turbine guide bearing.
The speed increaser low-head power station does not use a speed increaser, which directly affects the cost of the motor. For example, the ratio of the 1000kW 40-pole generator and the 1000kW 8-pole generator in Guangdong Yangjiang Shuangjie Power Plant is nearly three times, far exceeding the turbine price. If the speed increaser is used, the total price of the 1000kW 8-pole generator does not exceed 1000kW40 pole. Half of the generator price is conducive to the enthusiasm of low-head hydraulic resources development investment. Therefore, in order to increase the single unit capacity of the generator, reduce the volume, and reduce the cost, the speed increaser scheme should be preferred. In a unit with a speed increaser, the speed increase ratio and the transmitted power are large. The planetary gear speed increaser is often used in the shaft-through tubular turbine designed by Dongfeng Electric. The speed increaser of the speed increaser is generally larger, and an independent oil supply system is adopted. The generator and the speed increaser are connected by a pin coupling. Replacing the previous gear coupling with a pin coupling can effectively reduce noise and improve the operating environment.
In order to eliminate the torque fluctuation when the planetary gear speed increaser is driven, the matching coupling is a pin coupling. Since the pin and the pin hole are gap-fitted, and the pin is elastic, it allows the two shafts to have a displacement of 0.150.25 mm in the radial direction and a displacement of 0.53 mm in the axial direction, thereby obtaining the compensation of the relative displacement of the two axes. And the performance of buffer torque fluctuations. The pin is elastically deformed when the torque is transmitted, resulting in additional axial thrust and a large amount of axial displacement. In order to prevent the influence of axial turbulence on the radial tiling and to support the additional axial thrust, the front bearing of the generator must adopt a thrust radial bearing structure.
The design of bearings and oil supply system bearings is mainly based on the unit load and speed. For the shaft-through hydro-generator, since the generator and the turbine have two ways of connecting through the speed increaser, the pin coupling and the rigid direct connection, the corresponding bearing arrangement is also different.
The generator and the turbine are connected by the planetary gear speed increaser and the pin coupling. The water machine side is provided with two radial blades to support the weight of the rotating parts of the water machine, and one positive and negative thrust watts to support the positive , anti-water thrust; two radial blades are provided on the generator side to support the weight of the rotating parts of the generator and the single-sided magnetic pulling force. Considering that the nylon pin in the pin coupling will produce a certain deformation when transmitting torque, thereby generating additional axial force, a thrust structure is required in the generator side front radial bearing.
The generator and the turbine are rigidly connected in this way. One side of the water machine side is provided with one radial tiling to support the water machine tiling to support the positive and reverse water thrust, and two radial watts are supported to support the weight of the rotating part of the generator and one side. Magnetic pull.
Determination of lubrication parameters Due to the lower speed of the shaft-through tubular unit, longer shafting, larger load, larger shafting deformation, lower journal speed (usually at 35 m/s), the difficulty in bearing lubrication design lies in the oil. The wedge effect is poor and the oil film itself has low dynamic pressure capability. The minimum oil film thickness during operation of the unit is small, and the oil film is not easily formed when starting and stopping. According to the relevant information, the journaling speed of the journal is less than 10m/s. It is advisable to consider the dynamic and static pressure composite bearing. In the process of starting and stopping, when the speed is below 60% of the rated speed, the static pressure oil is put into operation, and during normal operation. It relies on dynamic pressure lubrication. In this way, a static pressure supply line must be provided in the oil supply system, so that the pipeline is complicated and the reliability of the device is poor. For this reason, attention is paid to the influence of the bearing structural parameters on the lubrication parameters during the lubrication calculation. If the journal is appropriately increased to increase the journal speed, at the same time, some basic parameters such as relative clearance of the bearing are passed! , unit pressure! The best matching of circumferential eccentricity e, radial eccentricity, aspect ratio 1/, filling factor, etc., with reasonable support structure, the static pressure oil load shedding device has been eliminated on many models. The relationship between the calculated value of the minimum oil film thickness of the same type and the actual value. Of course, in some units, even if necessary measures are taken, the design value of the minimum oil film thickness still does not reach the required safety factor. It is advisable to use dynamic and static pressure composite bearings.
Precautions for structural design Since the axis of the unit is more than 10 meters long, the bearing weight is much heavier than that of the conventional horizontal unit, resulting in a large deflection of the bearing after installation. The bearing position during operation is significantly changed when it is static. Therefore, the bearing support position, load, PV value selection of the bearing, and the oil sealing and sealing structure of the unit should be considered as a whole.
The turbine guide bearing uses an outer circulating oil-lubricated plain bearing with a spherical bearing surface. The bearing is composed of two parts, the bearing bush and the bearing body, and is divided into a half structure. The front and rear oil basins are arranged outside the bearing body, and the spherical surface of the lower part of the bearing body is matched with the spherical surface of the bearing seat. The bearing housing is mounted on the flange of the inner ring of the water guiding mechanism. Since the deflection of the main shaft and the eccentric value of the rotation are different under different operating conditions, the bearing can be self-adjusted under the action of the spherical surface, thereby ensuring the clearance between the main shaft journal and the bearing bush, so that the unit can operate safely and reliably. Considering the deformation of the water guiding mechanism under the action of gravity and the bearing to be sunk under the action of the rotating part after installation, the installation position is slightly raised and the gasket can be added. At the same time, the gap between the end cover of the turbine bearing bearing and the rotating shaft is appropriately enlarged in the case of ensuring sealing.
The thrust pad and the bearing support should be able to both make the block swing flexible and limit its excessive swing. Therefore, attention should be paid to the fit between the thrust pad and the bearing, the radial direction and the back. Consider the effect of the weight of the heavy thrust pad on the swing. The working surface roughness of the thrust plate should not be less than 0.8! There are high requirements for the geometrical tolerances such as the flatness of the flatness. The thrust plate usually adopts a structure in which the shaft is coupled by a key. The key is used to transmit the torque. The size should be selected according to the relevant data. The thrust disc and the shaft should adopt a small interference relationship.
The lubrication and cooling system of the oil supply system shaft through-flow unit generally adopts an outer circulation structure, that is, the generator and the turbine bearing share an oil supply system to provide centralized oil supply; and the static pressure composite bearing oil supply system also has a static pressure. The oil load shedding device provides static pressure oil to the bearing during the start-stop process.
3.5.5.1 Low-pressure oil system design The low-pressure oil system consists of a bearing high-position fuel tank, a bearing return tank, a bearing oil supply pump, an oil cooler, a hydraulic operating valve and a flow regulator. The circulating oil path of the lubricating oil is the bearing high position fuel tank guide bearing, the thrust bearing return oil tank oil pump oil cooler bearing high position fuel tank. The bearing oil supply uses a gear pump. The lubricating oil output by the oil pump passes through the oil filter and the oil cooler and enters the bearing high tank. The oil in the high tank is supplied to the respective shafts through the hydraulic regulators through the flow regulators. There are 2 oil filters and oil coolers, which are arranged in parallel. The design of the oil cooler has sufficient margin during design. When an oil cooler is used for a short time, the unit can continue to operate. There are gate valves on the inlet and outlet sides of the oil filter and oil cooler for use during maintenance. The cooling water of the oil cooler is supplied by technical water supply. The actual oil supply to the bearing can be adjusted by the flow regulator according to the unit's permissible settings. The return pipe of the water guide, the guide and the thrust bearing are arranged close to the return tank, and there are three baffle type flow signals.
This type of flow signal device can accurately measure the bearing flow rate when the lubricating oil is not filled with the pipe diameter to ensure the bearing oil supply amount.
3.5.5.2 High-position bearing oil tank design The volume of the high-bearing bearing oil tank should have sufficient margin. After the oil pump stops supplying oil, the unit can be safely operated.
The excess oil in the high fuel tank is drained back to the oil tank through the oil spill pipe. The pipe diameter design of the overflow pipe should be equal to the oil inlet pipe to ensure smooth oil spill. The oil input from the return tank has a high pressure. In order to prevent the oil tank from swelling, the oil pipe can be extended to the bottom of the tank or directly from the bottom of the tank to ensure the oil system parts to monitor the fuel tank. Oil level.
3.5.5.3 Return tank design The tank volume should be designed to meet the sum of the volume of the high bearing oil tank, the bearing oil chamber, the pipeline, and the normal operation after venting. The fuel tank is equipped with automatic components such as oil level annunciator and oil mixing signal annunciator. The level annunciator on the return tank sends an alarm signal when its liquid level drops to the lowest point.
The electromagnetic design of the base number is determined to be low, and the number of motors is generally expected to have a larger outer diameter of the core, so that more stator slots are selected, which will make the generator have a high and short shape. Due to the horizontal shaft installation, the foot plates on both sides of the machine base are fastened by bolts. When the unit is suddenly short-circuited, the force arm acting on the top of the machine base is longer, which will generate a large subversion torque; at the same time, due to the high and short shape Will deteriorate the strength and radial stiffness of the generator. Due to the limitation of the stator base to the stator core, the stator core cannot move freely under the influence of self-weight, single-sided magnetic pull force, and thermal expansion, which will cause the core punch to be pressed. If the radial component force is greater than the inter-plate friction force of the iron core punching piece, it will cause a large deformation of the inner circle of the generator core, thereby forming a large air gap ellipticity, and the shape of the air gap changes accordingly, increasing The harmonic component of the generator output voltage reduces the power generation quality of the generator. However, too small an outer diameter of the core will cause heat dissipation in the rotor. Therefore, when determining the electromagnetic scheme, the frame number needs to be carefully selected. When determining the specific structure of the stator core, such as the lap joint of the punching piece and the lamination method of the iron core, etc. The impact is fully considered.
The determination of the air gap is due to the low speed and the number of poles. At the same time, the choice of the frame number is limited, so that the pole pitch of the generator is small, the magnetic flux leakage of the magnetic pole system is increased, the reactance is larger than that of the conventional motor, and the pole magnet of the pole core is magnetic. The density is higher, and the required excitation ampere is more, which makes the rotor difficult to dissipate heat. In this way, the value of the air gap needs to be reduced, and the minimum value of the air gap is restricted by the convenience of installation and the safety of the operation of the unit. Therefore, when selecting the air gap, it is necessary to consider the rotor of the unit at maximum flight. The elastic deformation, and the ellipticity generated in the inner circle of the iron core under the influence of the self-weight of the stator core, the single-sided magnetic pull force, and the thermal expansion.
The value of the air gap is generally larger than the optimal electrical clearance. Thus, compared with the conventional unit, the reactance is larger, the short circuit ratio is larger, and the heating factor of the rotor is higher, but the safety of the unit operation can be ensured and the generator can be reduced. The harmonic component of the output voltage.
The stability of the structural characteristics of the generator. And when there is an oil level letter 3 on the fuel tank, the influence of this factor must be taken into account when installing the foundation by the automatic element hing. In the rigid straight bookmark4 shaft-through tubular hydro-generator is generally placed on the micro-bend over-flow channel. Due to the hydraulic relationship, the distance between the neutral line of the flow channel and the centerline of the shaft system is limited by the diameter of the turbine runner. In the online group of the machine, the foundation of the generator cannot be designed in the manner of a conventional horizontal hydro-generator. Generally, the basic bolts of the generator must be arranged across the flow channel. The floor size is large, and the structure of the large and small floor bolts is often used. .
Generator ventilation systems often use ducted ventilation cooling. Since the generator is located directly above the flow path, the bottom of the flow tube is usually not placed, but the top is vented, and the exhaust fan is placed in the hole through the wall. Due to the low speed of the generator, the wind pressure and air volume provided during operation are small, and the pole spacing is small, the flow resistance of the wind surface is relatively narrow, and the wind pressure drop is much larger than that of the conventional unit. In order to ensure the heat dissipation of the generator to the requirements of air volume and wind speed, the design of the air flow channel should be as smooth as possible, leaving no dead angles, and prevent parts with increased wind resistance from being placed locally. For example, the connection between the poles should be led to the end face of the yoke without being placed. Wind road; appropriately increase the size and angle of the blade to increase the wind pressure head; the transition of the flow channel should be smooth, reduce the sharp angle and so on. In addition, it is advisable to use a fan with a high head and a large air volume.
Conclusion The shaft extension and flow unit has the characteristics of high specific speed, high flow rate, high hydraulic efficiency and low investment. It is a good model for developing low head hydraulic resources. At present, the development of low-head hydraulic resources in China is booming, and higher requirements are placed on the performance, appearance and reliability of the selected low-head shaft-through tubular units. Dongfeng Motor Corporation will seize the opportunity of joining the WTO, the development of the western region and the development of hydropower, and continue to increase the intensity of technology development and innovation, starting from the variety, stand-alone capacity, unit efficiency and operational reliability, and further improve the product level.
Han Min 1972-), male, graduated from Chengdu University of Science and Technology in 1991, is now engaged in the design work of hydraulic turbines and inlet valves, engineers.
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