Grid valve for controlling intermediate stage of steam turbine to adjust steam extraction

Abstract

The grid valve for controlling the intermediate stage of the steam turbine to adjust steam extraction comprises a partition plate body and a rotating ring, and each of the partition plate body and the rotating ring comprises an upper semicircular ring part and a lower semicircular ring part; the contact surface of the upper semicircular ring part and the lower semicircular ring part is a split surface; the rotating ring is rotatably installed on the partition plate body, the rotating ring and the partition plate body are coaxially arranged, a plurality of hole channels with the same size are evenly formed in the partition plate body in the circumferential direction, a plurality of windows with the same size are evenly formed in the rotating ring in the circumferential direction, and when the rotating ring rotates till the hole channels correspond to the windows, the hole channels and the windows are matched to form a flow channel; according to the structural design, the window and the stationary blade are separated, the structural form of intermediate stage adjustment steam extraction of a traditional steam turbine is simplified, the optimal design of a single window is adopted, the efficiency of an intermediate adjustment stage of the steam turbine is remarkably improved, the method is suitable for constant-pressure stable operation of a steam turbine unit, valve rear pressure is controlled only by adjusting the opening degree of the grid valve, the structure is simple, and cost is low. And the manufacturing cost of the unit is low.

Description

Technical Field

[0001] The invention relates to a structure for adjusting steam extraction by an intermediate stage of a steam turbine, and in particular to a grid valve for controlling the adjustment of steam extraction by an intermediate stage of a steam turbine. Background Art

[0002] There are three common methods for adjusting steam extraction in steam turbines: 1. Use of seat cylinder valve structure: by installing a valve in the middle of the flow section to distribute the flow and control the steam extraction pressure, but this structure is specially designed to adapt to the industrial steam extraction of high-parameter and large-flow cogeneration units. It occupies a large space and is not suitable for use when the rated steam extraction volume is small.

[0003] 2. Adopting butterfly valve structure: Modifying the medium and low pressure connecting pipes and installing butterfly valves is the most common form of heating modification. However, the steam extraction from the connecting pipe is limited, and the maximum allowable steam extraction is limited to a certain range.

[0004] 3. Adopt high back pressure transformation method: This is a heating method with lower parameters. This method combines the design characteristics of the original unit, transforms the low-pressure flow part, and increases the exhaust steam back pressure heating. This method is suitable for the transformation of the unit and cannot be used universally. Summary of the invention

[0005] Based on the above description, the present invention provides a grid valve for controlling the steam extraction of the intermediate stage of the steam turbine to solve the technical problems in the prior art that the steam extraction means of the intermediate stage of the steam turbine occupies a large space, the steam extraction amount is limited, and it cannot be widely used.

[0006] The technical solution of the present invention to solve the above technical problems is as follows: A grid valve for controlling the steam extraction of the intermediate stage of a steam turbine, comprising a partition body and a rotating ring, wherein the partition body and the rotating ring both comprise an upper semicircular ring portion and a lower semicircular ring portion; the contact surface between the upper semicircular ring portion and the lower semicircular ring portion is a center dividing surface; The rotating ring is rotatably mounted on the partition body, the rotating ring and the partition body are coaxially arranged, the partition body is uniformly formed with a plurality of channels of uniform size along its circumference, and the rotating ring is uniformly formed with a plurality of windows of uniform size along its circumference, and when the rotating ring is rotated until the channels correspond to the windows, the channels and the windows cooperate to form a flow channel.

[0007] Compared with the prior art, the technical solution of this application has the following beneficial technical effects: The grid valve provided in the present application has a plurality of uniformly sized channels formed on the partition body along its circumference, and a plurality of uniformly sized windows formed on the rotating ring along its circumference. When the rotating ring rotates until the channels correspond to the windows, the channels and the windows cooperate to form a flow channel. This structural design separates the windows and the stationary blades, simplifies the structural form of the traditional steam turbine intermediate stage steam extraction adjustment, and adopts the optimized design of a single window, which significantly improves the efficiency of the intermediate regulating stage of the steam turbine. It is suitable for the constant pressure and stable operation of the steam turbine unit, and the pressure after the valve is controlled only by adjusting the grid valve opening. It has a simple structure and the manufacturing cost of the unit is low.

[0008] Based on the above technical solution, the present invention can also be improved as follows.

[0009] Furthermore, the number of the windows and the number of the channels are the same.

[0010] Furthermore, the shape and size of the window and the hole are exactly the same.

[0011] Furthermore, the spacing width between two adjacent channels is not less than the width of the window.

[0012] Furthermore, the upper semicircular ring portion and the lower semicircular ring portion of the partition body are positioned by positioning pins and are tightened and fixed by positioning bolts.

[0013] Furthermore, the upper semicircular ring portion and the lower semicircular ring portion of the rotating ring are positioned by positioning pins and are tightened and fixed by positioning bolts.

[0014] Furthermore, a rotating handle is formed by radially extending the lower semicircular ring portion of the rotating ring, and the rotating handle is used to be connected to a rotating partition adjustment lever, and the adjustment lever is connected to a hydraulic or steam pressure adjustment system.

[0015] Furthermore, a rotating ring groove is formed on one side of the partition body, and the rotating ring is installed in the rotating ring groove.

[0016] Furthermore, one side of the rotating ring contacts the partition body and the contact surface is filled with a Stellite alloy material, and a retaining edge structure of a predetermined height is formed on the outer side of the rotating ring groove.

[0017] Furthermore, the Stellite alloy material is a tungsten-cadmium-nickel alloy. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of a grid valve in a fully open state for controlling a steam turbine intermediate stage to adjust steam extraction provided by an embodiment of the present invention; Figure 2 A schematic diagram of a fully closed state of a grid valve for controlling an intermediate stage of a steam turbine to adjust steam extraction provided by an embodiment of the present invention; Figure 3 for Figure 1 Schematic diagram of the cross section along the BB direction; Figure 4 for Figure 1 Schematic diagram of the cross section along CC direction; Figure 5 This is a schematic diagram of the upper half of the embodiment of the present application after installation in a steam turbine. DETAILED DESCRIPTION

[0019] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0021] It will be appreciated that spatial relationship terms such as "under", "beneath", "below", "under", "above", "above", etc., may be used herein to describe the relationship of an element or feature shown in the figures to other elements or features. It will be appreciated that, in addition to the orientations shown in the figures, spatial relationship terms also include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is flipped, an element or feature described as "under other elements" or "under it" or "under it" will be oriented as "on" the other elements or features. Thus, the exemplary terms "under" and "under" may include both upper and lower orientations. In addition, the device may also include additional orientations (e.g., rotated 90° or other orientations), and the spatial descriptors used herein are interpreted accordingly.

[0022] like Figure 1-5 As shown, an embodiment of the present application provides a grid valve for controlling the steam extraction of the intermediate stage of a steam turbine, which includes a partition body 10 and a rotating ring 20, and the partition body 10 and the rotating ring 20 both include an upper semicircular ring part and a lower semicircular ring part; the contact surface between the upper semicircular ring part and the lower semicircular ring part is a center dividing surface.

[0023] For the convenience of description, the partition body 10 includes a partition upper semicircular ring 11 and a partition lower semicircular ring 12 , and the rotating ring 20 includes a rotating ring upper semicircular ring 21 and a rotating ring lower semicircular ring 22 .

[0024] The partition upper semicircular ring 11 and the partition lower semicircular ring 12 are combined to form an annular partition body 10 , and the rotating ring upper semicircular ring 21 and the rotating ring lower semicircular ring 22 are combined to form an annular rotating ring 20 .

[0025] The rotating ring 20 is rotatably mounted on the partition body 10, and the rotating ring 20 and the partition body 10 are coaxially arranged. The partition body 10 evenly forms a plurality of channels 10a of the same size along its circumference, and the rotating ring 20 evenly forms a plurality of windows 20a of the same size along its circumference.

[0026] When the rotating ring rotates until the hole 10a corresponds to the window 20a, the hole and the window cooperate to form a flow channel. Through the relative rotation of the rotating ring 20 and the partition body 10, the size of the connecting area between the hole 10a and the window 20a can be adjusted, thereby controlling the steam flow in the flow channel.

[0027] Preferably, the number of the windows 20a and the channels 10a is the same, ensuring that a flow channel can be formed at each channel 10a position by changing the relative position of the windows 20a, thereby improving the flow efficiency of the steam flow in the flow channel.

[0028] In the embodiment of the present application, the window 20a and the hole 10a are exactly the same in shape and size, so that when the window 20a and the hole 10a completely correspond, all areas of the hole 10a form steam flow channels, thereby maximizing the steam flow channels.

[0029] Among them, the interval width between two adjacent channels 10a is not less than the width of the window 20a. Such a structural design ensures that the window 20a and the channel 10a can form a completely staggered relative position relationship as they rotate, ensuring that the steam flow channel can achieve a fully closed design.

[0030] Preferably, the upper semicircular ring 11 and the lower semicircular ring 12 of the partition are positioned by positioning pins and fixed by positioning bolts, and correspondingly, the upper semicircular ring 21 and the lower semicircular ring 22 of the rotating ring are also positioned by positioning pins and fixed by positioning bolts.

[0031] In a preferred embodiment of the present application, the lower semicircular ring 22 of the rotating ring extends radially to form a rotating handle 221, and the rotating handle 221 is used to connect with the rotating baffle adjusting lever. The adjusting lever is connected to a hydraulic or steam pressure regulating system. The hydraulic or steam pressure regulating system acts on the rotating baffle adjusting lever to control the rotation of the rotating ring 20, thereby realizing the opening and closing of the steam flow channel and the flow rate adjustment.

[0032] A rotating ring groove 10 b is formed on one side of the partition body 10 , and the rotating ring 20 is installed in the rotating ring groove 10 b . A retaining edge structure with a predetermined height is formed on the outer side of the rotating ring groove 10 b to effectively prevent the rotating ring 20 from axial movement on the partition body 10 .

[0033] One side of the rotating ring 20 contacts the partition body 10 and the contact surface is filled with a Stellite alloy material, which is a tungsten-cadmium-nickel alloy.

[0034] Specifically, the partition body 10 is divided into two semicircles, namely, an upper semicircular ring 11 and a lower semicircular ring 12. A first positioning bolt 8 and a first positioning pin 9 are provided on the center dividing surface where the partition semicircular ring 11 and the lower semicircular ring 12 are in contact, and a lever 7 is provided on its outer peripheral surface to connect with the cylinder.

[0035] The partition body 10 is evenly provided with a plurality of holes 10a along the circumferential direction, and the holes 10a correspond one to one with the windows 20a provided on the rotating ring 2, and there is no stationary blade behind the holes 10a; the rotating ring 20 is divided into two upper and lower semicircles, namely, an upper semicircular ring 21 and a lower semicircular ring 22, and the rotating ring 20 is located in the rotating ring slot 10b of the partition body 10; a second screw 4, a second positioning bolt 5 and a second positioning pin 6 are provided on the dividing surface of the rotating ring 20 for connection and compression; the contact part between the partition body 10 and the rotating ring 20 is filled with a tungsten-cadmium-nickel alloy 3 to ensure rotation stability while improving corrosion resistance and wear resistance. When the window 20a on the rotating ring 1 is in a fully corresponding position with the hole 10a, the partition valve is in a fully open state, such as Figure 1 As shown, accordingly, the window 20a is completely offset from the channel 10a, and the partition valve is in a fully closed state. Figure 2 shown.

[0036] The grid valve for adjusting steam extraction in the intermediate stage of the steam turbine provided in the present application adopts a structure in which the stationary blades and windows are separated, which simplifies the structure of the traditional intermediate adjustment steam extraction so that no pressure loss is generated when steam passes through. Under high temperature and high pressure working conditions, the stationary blades are susceptible to corrosion and fouling, and the grid valve avoids the occurrence of such phenomena. In addition, the grid valve adopts a window of the same size designed on the rotating ring to ensure the uniformity and stability of the steam flow and improve the flexibility and adaptability of the equipment.

[0037] In summary, the grid valve system design for the intermediate adjustment and extraction of steam turbine proposed in this patent significantly improves the efficiency of the intermediate regulating stage of the steam turbine by separating the stationary blades and windows and adopting the optimized design of a single model window. It is suitable for the constant pressure and stable operation of the steam turbine unit. The pressure after the valve is controlled only by adjusting the opening of the grid valve. It has a simple structure and the manufacturing cost of the unit is low. Different from the traditional intermediate adjustment and extraction structure, it reduces the floor space and avoids the large plant floor space caused by the long shaft arrangement unit; at the same time, it meets the transportation of the unit as a whole skid, reduces the weight of the unit, and facilitates transportation. The structure proposed in this patent adopts a throttling steam distribution method. When the load of the unit changes, the temperature of each stage and the steam temperature are basically stable, which is conducive to the variable operating condition operation of the unit and ensures the safe and stable operation of the unit and the service life of the equipment.

[0038] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A grid valve for controlling the steam extraction of the intermediate stage of a steam turbine, characterized in that: It includes a partition body and a rotating ring, wherein the partition body and the rotating ring each include an upper semicircular ring portion and a lower semicircular ring portion; the contact surface between the upper semicircular ring portion and the lower semicircular ring portion is a mid-dividing surface; The rotating ring is rotatably mounted on the partition body, the rotating ring and the partition body are coaxially arranged, the partition body is uniformly formed with a plurality of channels of uniform size along its circumference, and the rotating ring is uniformly formed with a plurality of windows of uniform size along its circumference, and when the rotating ring is rotated until the channels correspond to the windows, the channels and the windows cooperate to form a flow channel.

2. The grid valve for controlling steam turbine intermediate stage to adjust steam extraction according to claim 1, characterized in that: The number of the windows is the same as the number of the holes.

3. The grid valve for controlling steam extraction of the intermediate stage of a steam turbine according to claim 1, characterized in that: The shape and size of the window and the hole are exactly the same.

4. The grid valve for controlling steam extraction of the intermediate stage of a steam turbine according to claim 3, characterized in that: The spacing width between two adjacent channels is not less than the width of the window.

5. The grid valve for controlling steam extraction of the intermediate stage of a steam turbine according to claim 4, characterized in that: The upper semicircular ring part and the lower semicircular ring part of the partition body are positioned by positioning pins and are compressed and fixed by positioning bolts.

6. The grid valve for controlling steam extraction of the intermediate stage of a steam turbine according to claim 4, characterized in that: The upper semicircular ring part and the lower semicircular ring part of the rotating ring are positioned by positioning pins and are compressed and fixed by positioning bolts.

7. The grid valve for controlling steam extraction of the steam turbine intermediate stage according to claim 6, characterized in that: The lower semicircular ring portion of the rotating ring is extended radially to form a rotating handle, and the rotating handle is used to be connected to the rotating partition regulating lever, and the regulating lever is connected to a hydraulic or steam pressure regulating system.

8. The grid valve for controlling steam extraction of the steam turbine intermediate stage according to claim 6, characterized in that: A rotating ring clamping groove is formed on one side of the partition body, and the rotating ring is installed in the rotating ring clamping groove.

9. The grid valve for controlling steam extraction of the intermediate stage of a steam turbine according to claim 8, characterized in that: One side of the rotating ring contacts the partition body and the contact surface is filled with a Stellite alloy material. A retaining edge structure with a predetermined height is formed on the outer side of the rotating ring groove.

10. The grid valve for controlling steam extraction of the steam turbine intermediate stage according to claim 9, characterized in that: The Stellite alloy material is a tungsten-cadmium-nickel alloy.

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