Method for improving the life of a water turbine guide vane

Abstract

A method for improving the service life of a water turbine guide mechanism, comprising the following steps: a. installing water turbine blades on a water turbine bottom ring, the blade shafts of the water turbine blades being able to rotate in the bottom ring; b. providing a sealing groove on one surface of one end of the water turbine blades, and providing a sealing strip on the surface opposite to the groove of the other end of the water turbine blades, the sealing strips of adjacent two water turbine blades being clamped with each other; c. providing a water turbine blade limiting mechanism on the upper part of the blade shafts of the water turbine, the water turbine blade limiting mechanism comprising an adjusting ring slidingly sleeved on the blade shafts of the water turbine, the top surface of the adjusting ring being fixed on the extension end of an electric push rod, the adjusting ring being able to slide up and down along the blade shafts of the water turbine under the action of the electric push rod, and the bottom surface of the adjusting ring between the blade shafts of adjacent two water turbine blades being provided with a limiting block. The present application can be firmly closed when the water turbine stops running, can reduce the abrasion of the blade shafts, greatly improve the service life of the blade shafts, and improve the performance of the water turbine.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of water turbine, and particularly relates to a method for prolonging the service life of a water guide mechanism of a water turbine. BACKGROUND

[0002] The water flow from the water guide chamber to the water turbine runner needs to pass through the water guide mechanism and then enter the runner. The main function of the water guide mechanism is to adjust the flow of the water turbine according to the change of the load of the power system, so as to meet the requirement of the system on the output of the unit; and to form and change the water flow circulation of the runner, so as to meet the requirement of the water turbine on the water flow circulation before entering the runner. The change of the water flow circulation of the runner is realized by rotating the angle of the guide vane to open the guide vane, half open the guide vane or fully open the guide vane. When the runner stops working, the guide vane must be rotated to make the head and tail of the adjacent guide vanes completely overlap, so as to cut off the water flow. At present, the cross section of the guide vane is streamline-shaped, similar to an airfoil, and the guide vane rotates around the guide vane shaft. The guide vane shaft is rotated through the rotating mechanism, so as to drive the guide vane to rotate with the guide vane shaft. The rotation of the guide vane shaft can change the opening angle of the guide vane and control the size of the water flow. The flow state of the water flow between the guide vanes is shown by arrows. Figure 3 and Figure 4 . Figure 2 is the closed position of the guide vane, and the water flow is cut off. When the unit is shedding load, the guide vane is closed to stop the operation of the water turbine; Figure 3 and Figure 4 is the position of the guide vane rotated to the medium opening degree and the large opening degree. The water flow direction is shown by arrow lines. The size and angle of the water flow entering the runner can be changed by changing the angle of the guide vane. Since the structure of the guide vane is streamline-shaped, the guide vane cannot be tightly closed after the head and tail of the guide vane overlap, and a small amount of water flow will flow into the runner through the gap of the overlap, resulting in water loss and failing to achieve the effect of stopping the operation of the runner. In addition, when the guide vane is completely closed, the water flow impacts the water-facing surface of the guide vane, causing small amplitude vibration of the guide vane, which affects the service life of the guide vane shaft. SUMMARY

[0003] The purpose of the present application is to provide a method for prolonging the service life of the water guide mechanism of a water turbine, which can tightly close when the water turbine stops operating, reduce water loss, reduce the abrasion of the vane shaft after the guide vane is completely closed, greatly prolong the service life of the vane shaft and improve the performance of the water turbine.

[0004] To achieve the above purpose, the present application adopts the following technical scheme:

[0005] A method for prolonging the service life of the water guide mechanism of a water turbine, comprising the following steps:

[0006] a. installing the water turbine vane on the bottom ring of the water turbine according to the conventional method, and the vane shaft of the water turbine vane can rotate in the bottom ring;

[0007] b. One surface at one end of the water wheel blade is provided with a sealing groove, the other end of the water wheel blade is provided with a sealing strip opposite the groove, and the sealing strips of the adjacent two water wheel blades are clamped with each other;

[0008] c. A water wheel blade limiting mechanism is arranged on the upper part of the water wheel blade rotating shaft, the water wheel blade limiting mechanism comprises an adjusting ring slidingly sleeved on the water wheel blade rotating shaft, the top surface of the adjusting ring is fixed to the telescopic end of the electric push rod, and the adjusting ring can slide up and down along the water wheel blade rotating shaft under the action of the electric push rod, and the bottom surface of the adjusting ring between the adjacent two water wheel blade rotating shafts is provided with a limiting block;

[0009] d. When the water wheel is running, the adjusting ring is stationary, the limiting block is away from the water wheel blade, and the water wheel blade is normally opened; when the water wheel needs to stop, the water wheel blade is completely closed, the adjusting ring slides downward under the action of the electric push rod, and the limiting block moves downward to tightly adhere to the far water side surface of one end of the water wheel blade, so that the impact on the water surface of the water wheel blade is reduced.

[0010] The above-mentioned method for prolonging the service life of the water wheel guide water mechanism, the top surface of the adjusting ring is fixed to the telescopic end of the electric push rod, the fixed end of the electric push rod is fixed to the connecting plate, and the connecting plate is fixed to the side plate.

[0011] The above-mentioned method for prolonging the service life of the water wheel guide water mechanism, the sealing strip is in the shape of a trapezoid, the lower base as the long side of the trapezoid is fixedly connected with the water wheel blade, and the upper base as the short side of the trapezoid is transitionally provided with a circular arc between the two sides; and the corresponding sealing groove is also in the shape of a trapezoidal groove.

[0012] By adopting the above technical solutions, the present application has the following technical effects:

[0013] The water wheel blade of the present application adopts the structure of the sealing strip and the sealing groove matched at the head and tail, can tightly close the adjacent guide vanes when the water wheel stops working, tightly seal the head and tail of the adjacent guide vanes through the mutual cooperation of the sealing groove and the sealing strip, and adopts the trapezoidal structure of the sealing groove and the sealing strip, which will not affect the speed and pressure of the water flow, thereby reducing the loss of the water flow during the operation of the unit, and the circular arc transition design of the sealing groove and the sealing strip can enhance the wear resistance of the blade, reduce the wear of the blade, and prolong the service life of the impeller. The present application can tightly close when the water wheel stops running, reduce the loss of the water flow, reduce the wear of the blade rotating shaft after the guide vanes are completely opened, greatly improve the service life of the blade rotating shaft, and improve the performance of the water wheel. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a structural schematic diagram of the present application;

[0015] Figure 2 is a schematic diagram of the completely closed state of the water wheel blade;

[0016] Figure 3 is a schematic diagram of the water turbine blade in a semi-open state of the present application;

[0017] Figure 4 is a schematic diagram of the water turbine blade in a fully open state of the present application;

[0018] Figure 5 is a schematic diagram of the structure of the present application without the water turbine blade limiting mechanism installed;

[0019] Figure 6 is a schematic diagram of the water turbine blade structure of the present application;

[0020] Figure 7 is Figure 6 is an enlarged schematic diagram of part A. DETAILED DESCRIPTION

[0021] The present application will be described in detail below in conjunction with the drawings and specific embodiments.

[0022] In the drawings, 1. sealing strip, 2. sealing groove, 3. water turbine blade, 4. bottom ring, 5. side plate, 6. connecting plate, 7. rubber pad, 8. adjusting ring, 9. limiting block, 10. rubber pad.

[0023] The water flow from the water diversion chamber to the water turbine runner needs to pass through the water guide mechanism to enter the runner. The main functions of the water guide mechanism are: adjusting the water turbine flow according to the changes in the load of the power system to meet the requirements of the system on the unit output; forming and changing the water flow circulation into the runner to meet the requirements of the water turbine on the water flow circulation before entering the runner. The guide vane must be closed to cut off the water flow when the runner stops working. As the main mixed-flow water turbine and the axial-flow water turbine, the water is radially introduced into the working area of the runner. This type of water guide mechanism is called radial water guide mechanism. The radial water guide mechanism is composed of multiple guide vanes, all of which can rotate synchronously around their own guide vane rotation shafts, like a louvered curtain. Multiple water turbine guide vanes are arranged at the outlet of the spiral casing, and the water turbine guide vanes are installed on the bottom ring. The flow state of the water flow between the water turbine guide vanes is shown in Figure 3 and Figure 4 , the arrow lines represent the direction of the water flow. Figure 2 is the closed position of the guide vane, the water flow is cut off, and when the unit is shedding load, the water turbine guide vane is closed to stop the operation of the water turbine; Figure 3 and Figure 4The water flow direction is shown by the arrow line in the figure. The water flow size and angle entering the runner can be changed by changing the angle of the guide vane. The operation state of the unit can be improved by adjusting the angle of the guide vane. The attack angle of the runner blade and the angle of the guide vane can be adjusted simultaneously for the axial flow water turbine, so that high operation efficiency can be achieved under various working conditions. The guide vane of the water turbine is synchronously rotated, and is driven by a servomotor. The transmission mechanism is composed of two servomotors and a control ring. The servomotor is fixed on the water turbine base, and the control ring can rotate around the main shaft of the water turbine. The servomotor is a hydraulic servo mechanism, which is mainly composed of a cylinder, a piston, a piston push-pull rod and the like. Under the action of the hydraulic pressure, the piston rod is pushed and pulled to drive the control ring to rotate left and right. The guide vane shaft of the water turbine is fixed with a connecting plate (guide vane arm). One end of the connecting rod is connected to the connecting plate, and the other end of the connecting rod is connected to the control ring. When the control ring rotates, the connecting rod is driven. One end of the connecting rod is fixed on the top of the water turbine shaft, and the connecting rod drives the water turbine guide vane to rotate.

[0024] The application relates to a method for prolonging the service life of a water turbine guide vane mechanism. Figures 1-7 As shown in the figure, the method comprises the following steps:

[0025] a. water turbine blades are installed on a bottom ring 4 according to a conventional method. The blade shaft of the water turbine blade can rotate in the bottom ring 4;

[0026] b. a sealing groove 2 is arranged on one surface of one end of the water turbine blade, and a sealing strip 1 is arranged on the surface opposite to the groove at the other end of the water turbine blade. The sealing strips of adjacent two water turbine blades are clamped with each other.

[0027] c. a water turbine blade limiting mechanism is arranged on the upper part of the blade shaft of the water turbine. The water turbine blade limiting mechanism comprises an adjusting ring 8 which is sleeved on the water turbine blade shaft and slides. The top surface of the adjusting ring is fixed on the extension end of an electric push rod 7. Under the action of the electric push rod, the adjusting ring can slide up and down along the water turbine blade shaft. Limiting blocks are arranged on the bottom surface of the adjusting ring between the blade shafts of adjacent two water turbine blades.

[0028] d. when the water turbine operates, the adjusting ring is stationary, and the limiting blocks 9 are away from the water turbine blade, so that the water turbine blade is normally opened. When the water turbine needs to stop, the water turbine blade is completely closed, the adjusting ring slides downward under the action of the electric push rod, and the limiting blocks move downward and closely adhere to the surface far from the water on one end of the water turbine blade, so that the impact on the water surface of the water turbine blade is reduced.

[0029] In the above method for prolonging the service life of the water turbine guide vane mechanism, the top surface of the adjusting ring is fixed on the extension end of the electric push rod 7. The fixed end of the electric push rod is fixed on a connecting plate 6, the connecting plate is fixed on a side plate 5, and the side plate is installed on the spiral case of the water turbine or the field wall on the side of the water turbine.

[0030] The method for prolonging the service life of the water turbine guide vane, the shape of the sealing strip is trapezoidal, the lower base as the long side of the trapezoid is fixedly connected with the water turbine blade, and the upper base as the short side of the trapezoid is transitionally provided with a circular arc between the two sides; the shape of the corresponding sealing groove is also trapezoidal. The lower base as the long side of the trapezoid is fixedly connected with the water turbine blade, and the upper base as the short side of the trapezoid is transitionally provided with a circular arc between the two sides; the shape of the corresponding sealing groove is also trapezoidal. The wear resistance can be improved by the transition design of the circular arc, the wear of the water turbine blade can be reduced, and the service life of the water turbine blade is prolonged.

[0031] The inner surface of the sealing groove is provided with a rubber pad 10, which can effectively reduce the friction resistance during the operation of the impeller, thereby reducing the vibration noise during the operation of the unit.

[0032] When the water turbine stops working and the water turbine blades are closed, the water flow impacts the water turbine blades, and the adjacent water turbine blades are sealed by lapping, and the sealing is more airtight by the cooperation of the sealing strip and the sealing groove, so that the water flow is completely closed and the possibility of the water flow flowing through the gap between the adjacent water turbine blades to the runner is cut off. At this time, the water flow impacts the water turbine blade surface, so that the water turbine blade bears a certain impact force, especially at the lapping part of the adjacent water turbine blades, which is easy to be impacted by the water flow and vibrate. At this time, the electric push rod is started to move the adjusting ring downward to top the limiting block on the far water side surface of one end of the water turbine blade, thereby reducing the impact on the water turbine blade surface and avoiding the vibration caused by the water flow impacting the lapping part of the water turbine blade.

[0033] The water turbine blade of the application adopts the structure of the sealing strip and the sealing groove matched at the head and tail, which can close tightly between the adjacent guide vanes when the water turbine stops working, and the head and tail of the adjacent guide vanes are sealed firmly by the cooperation of the sealing groove and the sealing strip. The sealing groove and the sealing strip adopt a trapezoidal structure, which does not affect the speed and pressure of the water flow, thereby reducing the loss of the water flow during the operation of the unit. The wear resistance of the blade can be improved by the transition design of the circular arc of the sealing groove and the sealing strip, the wear of the blade can be reduced, and the service life of the water turbine blade is prolonged. The application can close tightly when the water turbine stops working, and the loss of the water flow is reduced. At this time, the electric push rod is started to move the adjusting ring downward to top the limiting block on the far water side surface of one end of the water turbine blade, thereby reducing the impact on the water turbine blade surface and avoiding the vibration caused by the water flow impacting the lapping part of the water turbine blade. The application is equivalent to the secondary protection of the water turbine blade, and the service life of the water turbine guide vane is greatly improved, and the performance of the water turbine is improved.

[0034] The above merely describes the preferred embodiments of the present application, and it should be noted that for those skilled in the art, several changes and improvements can be made without departing from the overall concept of the present application, and these should be considered as the protection scope of the present application, and these will not affect the effect and practicality of the present application.

Claims

1. A method for increasing the life of a water turbine's water guide mechanism, characterized by, The method comprises the following steps: a. installing the water turbine blades (3) on the water turbine bottom ring in a conventional way, the blade rotating shaft of the water turbine blades being able to rotate in the bottom ring; b. setting a sealing groove (1) on one surface of one end of the water turbine blade, setting a sealing strip (2) on the surface opposite to the groove of the other end of the water turbine blade, and making the sealing strips of the adjacent two water turbine blades clasp each other with the sealing grooves; c. setting a water turbine blade limiting mechanism on the upper part of the blade rotating shaft of the water turbine, the water turbine blade limiting mechanism comprising an adjusting ring (8) slidingly sleeved on the water turbine blade rotating shaft, the top surface of the adjusting ring being fixed on the extension end of an electric push rod (7), the adjusting ring being able to slide up and down along the water turbine blade rotating shaft under the action of the electric push rod, and the bottom surface of the adjusting ring between the adjacent two water turbine blade rotating shafts being provided with a limiting block; d. when the water turbine is running, the adjusting ring is not moved, the limiting block is away from the water turbine blade, and the water turbine blade is normally opened; when the water turbine needs to stop, the water turbine blade is completely closed, the adjusting ring slides downward under the action of the electric push rod, the limiting block moves downward and closely abuts against the surface far from the water on one end of the water turbine blade, and the impact on the water surface of the water turbine blade is reduced; the fixed end of the electric push rod is fixed on a connecting plate (6), and the connecting plate is fixed on a side plate (5); the sealing strip is in the shape of a trapezoid, the lower base as the long side of the trapezoid is fixedly connected with the water turbine blade, the upper base as the short side of the trapezoid is provided with a circular arc transition between the two sides, and the corresponding sealing groove is also in the shape of a trapezoidal groove.

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