A desuperheating and pressure-reducing combined device

Abstract

The present invention discloses a desuperheating and pressure-reducing combined device, which comprises a steam pressure-reducing regulating valve, a mixing pipe and a desuperheating water nozzle; the air inlet of the steam pressure-reducing regulating valve is connected to a primary steam pipeline, and the air outlet of the steam pressure-reducing regulating valve is connected to the air inlet of the mixing pipe; the air outlet of the mixing pipe is connected to a secondary steam pipeline; a desuperheating water nozzle is installed on the side wall of the mixing pipe, and the water inlet of the desuperheating water nozzle is communicated with a desuperheating water supply device that provides desuperheating water; the steam pressure-reducing regulating valve adopts a combined steam pressure-reducing regulating valve, which comprises a valve body. There are at least 2 valve seats arranged in the inner cavity of the valve body. One valve core is arranged in each valve seat. A separate valve rod is connected to the upper end of each valve core. The multiple valve seats are arranged in a stepped and staggered manner up and down in the valve body. The upper part of the separate valve rod is connected to a valve rod connecting piece. The top of the separate valve rod is threadedly engaged with one end of a main valve rod, and the other end of the main valve rod is connected to the output end of an actuator.

Description

Technical Field

[0001] The present invention relates to a desuperheating and pressure-reducing combined device, in particular to a desuperheating and pressure-reducing combined device suitable for steam within various steam flow ranges. Background Art

[0002] In recent years, a large number of industrial steam supplies have been changed from self-provided small boilers to centralized supply by large thermal power plants. Desuperheating and pressure-reducing valves are often used to adjust the pressure and temperature of primary steam to meet the requirements of steam use parameters. The main performance indicators for evaluating desuperheating and pressure-reducing valves are the adjustment accuracy of the flow rate, pressure, and temperature of secondary steam. The larger the adjustment range of secondary steam flow rate, and the more accurate the pressure and temperature are, the better the performance of the desuperheating and pressure-reducing valve; conversely, the worse the performance. Under the condition of certain steam parameters during actual operation, to ensure the best performance of the desuperheating and pressure-reducing valve, the best working range of the steam pressure-reducing regulating valve and the best atomizing water volume of the desuperheating water system nozzle are also certain. During actual operation, the requirements for the pressure and temperature of secondary steam are relatively fixed, but the flow rate often changes at any time according to the needs of the user side. This requires the pressure-reducing regulating valve and the desuperheating water regulating valve to be adjusted at any time to ensure the parameters required by the user. Once the flow rate required by the user side differs greatly from the rated design flow rate and exceeds the adjustment ranges of the pressure-reducing regulating valve and the desuperheating water regulating valve, the flow rate, pressure, and steam temperature of secondary steam cannot be guaranteed. How to accurately adjust the pressure and temperature of secondary steam when the operating flow rate of the desuperheating and pressure-reducing valve differs greatly from the design flow rate is a long-existing issue worthy of research and improvement. Summary of the Invention

[0003] To solve the above problems, a desuperheating and pressure-reducing combined device is provided.

[0004] The purpose of the present invention is achieved in the following manner:

[0005] A temperature reduction and pressure reduction combined device, said device comprising a steam pressure reduction regulating valve 2, a mixing pipe 7 and a desuperheating water nozzle 8; the inlet of the steam pressure reduction regulating valve 2 is connected to the primary steam pipeline, and the outlet of the steam pressure reduction regulating valve 2 is connected to the inlet of the mixing pipe 7; the outlet of the mixing pipe 7 is connected to the secondary steam pipeline; a desuperheating water nozzle 8 is installed on the side wall of the mixing pipe 7, and the water inlet of the desuperheating water nozzle 8 is communicated with a desuperheating water supply device that provides desuperheating water; the steam pressure reduction regulating valve 2 adopts a combined steam pressure reduction regulating valve, including a valve body 21, at least 2 valve seats 22 are arranged in the inner cavity of the valve body 21, 1 valve core 6 is arranged in each valve seat 22, a sub-valve rod 5 is connected to the upper end of each valve core 6, and a plurality of valve seats 6 are arranged in a stepped and staggered manner up and down in the valve body 21, the upper part of the sub-valve rod 5 is connected to a valve rod connecting piece 4, a threaded sleeve 41 corresponding to the sub-valve rod 5 is arranged in the valve rod connecting piece 4, the upper part of the sub-valve rod 5 is arranged in the threaded sleeve 41, the top of the sub-valve rod 5 is threadedly engaged with one end of the main valve rod 3, and the other end of the main valve rod 3 is connected to the output end of the actuator 1, and the actuator 1 drives the main valve rod 3 to lift and rotate.

[0006] The main valve rod 3 is threadedly engaged with different sub-valve rods 5 at different positions, driving the sub-valve rods 5 to lift by screwing in and out in the threaded sleeve 41.

[0007] The input end of the actuator is electrically connected to a controller or a microcomputer.

[0008] A primary steam shut-off valve 10, a first temperature transmitter and a first pressure transmitter are installed on the primary steam pipeline, and a secondary steam shut-off valve 15, a second pressure transmitter and a second temperature transmitter are installed on the secondary steam pipeline; the primary steam shut-off valve 10, the first temperature transmitter, the first pressure transmitter, the secondary steam shut-off valve 15, the second pressure transmitter and the second temperature transmitter are all electrically connected to a controller or a microcomputer.

[0009] The desuperheating water supply device includes a desuperheating water tank, a desuperheating water main pipe, and at least 2 desuperheating water branch pipes. The water outlet of the desuperheating water tank is connected to the water inlet side of the desuperheating water main pipe, the water outlet side of the desuperheating water main pipe is respectively connected to the water inlet side of the desuperheating water branch pipes, the water outlet side of the desuperheating water branch pipes is connected to the desuperheating water nozzle 8, a desuperheating water main pipe shut-off valve is arranged on the desuperheating water main pipe, a desuperheating water regulating valve 13 and a desuperheating water check valve 14 are successively arranged on the desuperheating water branch pipes, and desuperheating water shut-off valves 12 are arranged on both sides of the desuperheating water regulating valve.

[0010] Advantages of the present invention: Compared with the prior art, each valve core of the desuperheating and pressure-reducing combined device of the present invention has multiple opening options to correspond to different operating flows; the operating valve cores can be one, or multiple or all; this desuperheating and pressure-reducing combined device can adapt to changes in various operating flows and still have good pressure and temperature stabilization effects under various flow conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a schematic diagram of the overall structure of the present invention.

[0012] Figure 2 is a schematic diagram of the use of the present invention.

[0013] Figure 3 is a schematic diagram of the structure of the steam pressure-reducing regulating valve according to an embodiment of the present invention.

[0014] Figure 4 is a schematic diagram of the structure of the valve stem connecting member according to an embodiment of the present invention.

[0015] Figure 5 is Figure 1 the sectional view taken along line A-A in

[0016] Where 1 - actuator, 2 - steam pressure-reducing regulating valve, 21 - valve body, 22 - valve seat, 23 - inlet port, 24 - outlet port, 3 - main valve stem, 4 - valve stem connecting member, 41 - threaded sleeve, 5 - sub-valve stem, 6 - valve core, 7 - mixing pipe, 8 - desuperheating water nozzle, 9 - safety valve, 10 - primary steam shut-off valve, 11 - desuperheating water header shut-off valve, 12 - desuperheating water shut-off valve, 13 - desuperheating water regulating valve, 14 - desuperheating water check valve, 15 - secondary steam shut-off valve, 16 - desuperheating and pressure-reducing device working steel pipe. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] The present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0018] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same technical meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0019] Such as Figure 1-4As shown in the figure, a temperature and pressure reduction combined device, the device includes a steam pressure reduction regulating valve 2, a mixing pipe 7 and a desuperheating water nozzle 8; the inlet 23 of the steam pressure reduction regulating valve 2 is connected to the primary steam pipeline, and the outlet 24 of the steam pressure reduction regulating valve 2 is connected to the inlet of the mixing pipe 7; the outlet of the mixing pipe 7 is connected to the secondary steam pipeline; the desuperheating water nozzle 8 is installed on the side wall of the mixing pipe 7, and the water inlet of the desuperheating water nozzle 8 is communicated with a desuperheating water supply device that provides desuperheating water; the steam pressure reduction regulating valve 2 adopts a combined steam pressure reduction regulating valve, including a valve body 21, at least 2 valve seats 22 are arranged in the inner cavity of the valve body 21, 1 valve core 6 is arranged in each valve seat 22, a separate valve rod 5 is connected to the upper end of each valve core 6, and a plurality of valve seats 6 are arranged in a stepped and staggered manner up and down in the valve body 21, the upper part of the separate valve rod 5 is connected to the valve rod connecting piece 4, a threaded sleeve 41 corresponding to the separate valve rod 5 is arranged in the valve rod connecting piece 4, the upper part of the separate valve rod 5 is arranged in the threaded sleeve 41, the top of the separate valve rod 5 is threadedly engaged with one end of the main valve rod 3, and the other end of the main valve rod 3 is connected to the output end of the actuator 1, and the actuator 1 drives the main valve rod 3 to lift and rotate.

[0020] The main valve rod 3 is threadedly engaged with different separate valve rods 5 at different positions, driving the separate valve rods 5 to lift by screwing in and out in the threaded sleeve 41.

[0021] As Figure 3 shown, the inlet of the steam pressure reduction regulating valve 2 is one, and each valve seat 22 and valve core 6 correspond to an outlet 24.

[0022] The input end of the actuator is electrically connected to a controller or a microcomputer. The actuator is an electric (pneumatic) actuator of a valve, which is prior art. It mainly includes an electric motor and a gear transmission device. The electric motor is connected to the valve rod of the valve through a transmission device such as a gear, driving the valve rod of the valve to lift or rotate.

[0023] A primary steam shut-off valve 10, a first temperature transmitter and a first pressure transmitter are installed on the primary steam pipeline, and a secondary steam shut-off valve 15, a second pressure transmitter and a second temperature transmitter are installed on the secondary steam pipeline; the primary steam shut-off valve 10, the first temperature transmitter, the first pressure transmitter, the secondary steam shut-off valve 15, the second pressure transmitter and the second temperature transmitter are all electrically connected to a controller or a microcomputer.

[0024] The desuperheating water supply device includes a desuperheating water tank, a desuperheating water main pipe, and at least two desuperheating water branch pipes. The water outlet of the desuperheating water tank is connected to the water inlet side of the desuperheating water main pipe, the water outlet side of the desuperheating water main pipe is respectively connected to the water inlet sides of the desuperheating water branch pipes, the water outlet side of the desuperheating water branch pipes is connected to the desuperheating water nozzle 8, a desuperheating water main pipe switch valve 11 is provided on the desuperheating water main pipe, a desuperheating water regulating valve 13 and a desuperheating water check valve 14 are successively provided on the desuperheating water branch pipes, and desuperheating water switch valves 12 are provided on both sides of the desuperheating water regulating valve.

[0025] As Figure 1 shown, the steam pressure reducing and regulating valve 2 of the present invention is provided with three valve cores 6, namely valve core A, valve core B, and valve core C. The flow rate corresponding to valve core A is 20% of the total design flow rate, the flow rate corresponding to valve core B is 35% of the total design flow rate, and the flow rate corresponding to valve core C is 45% of the total design flow rate. When the required steam flow rate of the secondary steam is 10% of the total steam flow rate, the thread at the top of the sub-valve rod 5 connecting the main valve rod 3 and valve core A is engaged. After logical operation by the controller or microcomputer, the primary steam switch valve 10 is opened and an instruction is sent to the actuator 1. The actuator 1 drives the main valve rod 3 to rotate, thereby driving the sub-valve rod 5 to lift, opening the opening degree of valve core A of the steam pressure reducing and regulating valve 2, and adjusting the steam flow rate. At the same time, the desuperheating water switch valve 12 is opened, and the opening degrees of valve core A of the steam pressure reducing and regulating valve 2 and the desuperheating water regulating valve 13 are adjusted according to the temperature and pressure feedback signals of the secondary steam at the outlet of the steam pressure reducing and regulating valve 2, so that the temperature and pressure of the secondary steam are maintained at the required parameters; when the required steam flow rate of the secondary steam rises, the controller or microcomputer judges, through logical operation based on feedback signals such as flow rate signals and pressure signals, that the designed flow rate when valve core A and valve core B or valve core C operate in combination is closest to the required flow rate, and issues an instruction to open the corresponding valve core A and valve core B or valve core C of the steam pressure reducing and regulating valve 2 and the corresponding desuperheating water regulating valve 13 to operate together, so that the sum of the flow rates corresponding to the designed desuperheating and pressure reducing device in operation is the same as or close to the actual steam flow rate, ensuring that the designed working condition of the desuperheating and pressure reducing device is highly consistent with the actual working condition, enabling the pressure and temperature of the secondary steam to be more precisely controlled and achieving a better desuperheating and pressure reducing goal.

[0026] Figure 2As shown in the figure, it is a schematic diagram of the usage state of the desuperheating and pressure reducing device combination of the present invention. A first temperature transmitter and a first pressure transmitter are installed on the primary steam pipeline, and a secondary steam shut-off valve 15, a second temperature transmitter, and a second pressure transmitter are installed on the secondary steam pipeline. The secondary steam flow demand signal is transmitted to the controller or microcomputer. The controller or microcomputer issues an instruction through logical operation to select to open some or all of the desuperheating and pressure reducing valves and the corresponding desuperheating water systems that match it. The first pressure transmitter and the first temperature transmitter on the primary steam pipeline and the second pressure transmitter and the second temperature transmitter on the secondary steam pipeline transmit data signals to the controller or microcomputer. The controller or microcomputer issues an instruction to the actuators of the steam pressure reducing regulating valve and the desuperheating water regulating valve through logical operation to adjust the opening degrees of the steam pressure reducing regulating valve 2 and the desuperheating water regulating valve 13, so as to achieve fine adjustment of the steam and the desuperheating water and realize the target pressure and temperature of the secondary steam.

[0027] The principle of the present invention is: according to the demand for steam flow on the user side, select to start some or all of the valve cores of the steam pressure reducing regulating valve 2, so that the flow rates and velocities of the steam in each valve core of the steam pressure reducing regulating valve 2 and the mixing pipe all maintain a relatively reasonable data, and each desuperheating water system maintains a good atomization effect, so as to achieve that the pressure and temperature at the outlet of the desuperheating and pressure reducing device can maintain a high control accuracy under various flow rates, and the pressure and temperature of the secondary steam are relatively stable.

[0028] The opening selection of the valve core of the steam pressure reducing regulating valve 2 of the desuperheating and pressure reducing device combination of the present invention corresponds to different operating flow rates; the operating steam pressure reducing regulating valve cores can be 1, or multiple or all; this desuperheating and pressure reducing device combination can adapt to the changes of various operating flow rates and still has a good pressure stabilizing and temperature stabilizing effect under various flow conditions.

[0029] The above are only the preferred embodiments of the present invention. It should be noted that for those skilled in the art, without departing from the overall concept of the present invention, several changes and improvements can still be made, and these should also be regarded as the protection scope of the present invention.

Claims

1. A desuperheating and pressure-reducing combined device, characterized in that: The device includes a steam pressure reducing control valve (2), a mixing pipe (7) and a desuperheating water nozzle (8); the inlet of the steam pressure reducing control valve (2) is connected to the primary steam pipeline, and the outlet of the steam pressure reducing control valve (2) is connected to the inlet of the mixing pipe (7); the outlet of the mixing pipe (7) is connected to the secondary steam pipeline; the desuperheating water nozzle (8) is installed on the side wall of the mixing pipe (7), and the water inlet of the desuperheating water nozzle (8) is communicated with a desuperheating water supply device that provides desuperheating water; the steam pressure reducing control valve (2) adopts a combined steam pressure reducing control valve, including a valve body (21), at least 2 valve seats (22) are arranged in the inner cavity of the valve body (21), 1 valve core (6) is arranged in each valve seat (22), a separate valve rod (5) is connected to the upper end of each valve core (6), and the multiple valve cores (6) are arranged in a stepped and staggered manner up and down in the valve body (21). The upper part of the separate valve rod (5) is connected to a valve rod connecting part (4), a threaded sleeve (41) corresponding to the separate valve rod (5) is arranged in the valve rod connecting part (4), the upper part of the separate valve rod (5) is arranged in the threaded sleeve (41), the top of the separate valve rod (5) is threadedly engaged with one end of a main valve rod (3), and the other end of the main valve rod (3) is connected to the output end of an actuator (1), and the actuator (1) drives the main valve rod (3) to lift and rotate; Each valve seat and valve core of the steam pressure reducing control valve (2) correspond to an air outlet; The main valve rod (3) is threadedly engaged with different separate valve rods (5) at different positions, driving the separate valve rods (5) to lift by screwing in and out in the threaded sleeve (41).

2. The desuperheating and pressure-reducing combined device according to claim 1, wherein: The input end of the actuator is electrically connected to a controller or a microcomputer.

3. The desuperheating and pressure-reducing combined device according to claim 1, characterized in that: A primary steam shut-off valve (10), a first temperature transmitter and a first pressure transmitter are installed on the primary steam pipeline, and a secondary steam shut-off valve (15), a second pressure transmitter and a second temperature transmitter are installed on the secondary steam pipeline; the primary steam shut-off valve (10), the first temperature transmitter, the first pressure transmitter, the secondary steam shut-off valve (15), the second pressure transmitter and the second temperature transmitter are all electrically connected to a controller or a microcomputer.

4. The desuperheating and pressure reducing combined device according to claim 1, characterized in that: The desuperheating water supply device includes a desuperheating water tank, a desuperheating water main pipe, and at least 2 desuperheating water branch pipes. The water outlet of the desuperheating water tank is connected to the water inlet side of the desuperheating water main pipe, the water outlet side of the desuperheating water main pipe is respectively connected to the water inlet sides of the desuperheating water branch pipes, the water outlet sides of the desuperheating water branch pipes are connected to the desuperheating water nozzle (8), a desuperheating water main pipe shut-off valve is arranged on the desuperheating water main pipe, a desuperheating water regulating valve (13) and a desuperheating water check valve (14) are successively arranged on the desuperheating water branch pipes, and desuperheating water shut-off valves (12) are arranged on both sides of the desuperheating water regulating valve.

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