CN106439176A - Long-distance water supply pipe accident quick valve closing device and method - Google Patents

Abstract

The invention discloses a device and method for quickly closing a valve in an accident of a long-distance water supply pipeline. In the present invention, a valve linked with the rotating shaft of the hydraulic motor is set on one branch of the hydraulic motor. When the two branches of the hydraulic pipeline are connected, the total flow of the hydraulic pipeline is relatively large, the output speed of the hydraulic motor is relatively large, and the valve Faster rotation to achieve the purpose of quickly closing the valve. When the valve is closed to the inflection point, the flow in the hydraulic pipeline decreases, the output speed of the hydraulic motor decreases, and the closing speed of the valve decreases, achieving the purpose of slowly closing the valve. Adjusting the relative position of the ball and the axial column can change the opening of the valve when the handle is in contact with the straight rod, and can change the position of the inflection point during the closing process. For the open working condition, activate the reversing valve to switch the high-pressure end and the low-pressure end, so that the flow direction connected to the hydraulic motor is completely opposite, and the output speed of the hydraulic motor is opposite, so that the valve can be opened in a straight line.

Description

Device and method for quickly closing valve in case of long-distance water supply pipeline accident

technical field

The invention relates to the technical field of long-distance water supply engineering, and relates to a valve control device in long-distance water supply engineering, and a quick valve closing device and method for reducing pipeline water hammer pressure in the long-distance water supply system.

Background technique

Long-distance water delivery projects are an effective way to solve the uneven distribution of water resources in time and space, but the water hammer pressure generated during project operation will seriously threaten the safety of water delivery systems. The most common equipment in the water delivery system is the valve. For long-distance water delivery projects, the water flow can only be cut off by slowly closing the valve, and the huge water hammer pressure generated when the valve is closed can be controlled by controlling the closing speed of the valve. Under normal circumstances, the main function of conventional valves is to introduce head loss to adjust the flow rate. If a pipe burst occurs, the adjacent valves must be closed to reduce the impact of the burst. When an accident occurs in the project and the valve at the end of the pipeline needs to be closed urgently, a reasonable closing method must be adopted. When an accident occurs in the system, the corresponding valve and other control mechanisms should act quickly to remove the source of the accident. However, due to the long line of the water pipeline, once a pipe burst accident occurs, the pipeline flow will increase rapidly. If the valve is closed quickly, it may cause very large pressure. , causing secondary accidents.

In order to avoid excessive water hammer pressure and facilitate the operation of valves, the conventional method of closing in a straight line is generally adopted in long-distance water delivery projects. If the valve closing speed is too fast, a huge water hammer pressure will be generated, which will lead to continuous pipe burst accidents. Therefore, the closing of valves in long-distance water pipelines is a very slow process. Although slow valve closing can control the water hammer pressure, due to the long valve closing time and slow accident response time, the loss caused by the original accident is exacerbated to a certain extent. How to ensure that the valve is closed as soon as possible under the condition that the valve closing pressure satisfies the pipeline pressure standard, and the emergency pipeline is cut off has always been an urgent problem in this field. The present invention proposes and designs a method for quickly closing valves in long-distance water supply projects under the condition that the water hammer pressure meets the pipeline pressure bearing standard, so as to close the valves as soon as possible and speed up the accident response speed so as to reduce the losses caused by accidents.

Contents of the invention

Purpose of the invention: the conventional method of linear closure is generally adopted in long-distance water supply projects at present. If the valve is closed too quickly, a huge water hammer pressure will be generated, which will lead to continuous pipe burst accidents. Although slow valve closing can control the water hammer pressure, due to the long valve closing time and slow accident response time, the loss caused by the original accident is exacerbated to a certain extent. In order to overcome this shortcoming of the existing valves in water delivery projects, the present invention aims to provide a control device and method that can realize fast closing of valves in long-distance water supply projects.

Technical solution: A device of the present invention for quickly closing valves in long-distance water supply projects, including hydraulic oil tanks, hydraulic pipelines and hydraulic motors, the hydraulic motors are connected to the valves, and the hydraulic pipelines have parallel first A branch and a second branch, a control valve linked with a hydraulic motor is connected in series on the first branch. The oil enters the hydraulic motor from the high-pressure end of the hydraulic oil tank, and enters the low-pressure end from the other inlet of the hydraulic motor. The output speed of the hydraulic motor can be controlled by controlling the flow in the hydraulic pipeline, thereby controlling the closing speed of the valve.

Specifically, the control valve has a sphere, a rotating body is installed in the sphere, and there is a communication pipeline in the rotating body. The lower part of the rotating body is fixedly connected with the connecting rod, and the connecting rod is fixedly connected with the straight rod; , and drive the rotating body to rotate, thereby driving the connecting pipeline to rotate. When the straight rod rotates horizontally around the center of the sphere, it will drive the rotating body to rotate, so the branch with the sphere is cut off, the flow in the hydraulic pipeline is reduced, and the closing speed of the valve is reduced, achieving the purpose of fast first and then slow closing.

Specifically, the axial column of the hydraulic motor is fixedly connected to the valve stem of the valve, the axial column has a handle, and the handle is overlapped with the straight rod. Take the axial column as the center, the distance between the ball center and the axial column as the radius, keep the straight rod pointing to the axial column, adjust the position of the ball horizontally, you can change the opening of the valve when the handle is in contact with the straight rod, thereby changing the closing The location of the inflection point in the process.

Specifically, a throttling valve is connected in series on the main road of the hydraulic pipeline. The flow rate of the hydraulic motor determines the output speed of the hydraulic motor. The opening of the throttle valve in the hydraulic pipeline can be adjusted through calculation according to the valve closing and opening rules, and the flow rate in the hydraulic pipeline can be controlled by adjusting the throttle valve to change the pressure oil flow rate. The size, and then control the output speed of the hydraulic motor, so as to control the closing and opening speed of the valve.

Specifically, a reversing valve is arranged on the hydraulic pipeline. Starting the reversing valve can change the flow direction of the oil body in the hydraulic pipeline, thereby changing the direction of the output speed of the hydraulic motor, and realizing the purpose of opening the valve.

The present invention also proposes a method for quickly closing valves in long-distance water supply pipeline accidents using the above-mentioned device for quickly closing valves in accidents in long-distance water supply pipelines, which is suitable for rapid valve closing in accidents in long-distance water supply pipelines.

When the valve is closed quickly, the two branches of the high-pressure end of the hydraulic pipeline are connected. At this time, the total flow of the hydraulic pipeline is relatively large, the output speed of the hydraulic motor is relatively large, and the rotation speed of the axial column is relatively fast, which drives the valve to rotate rapidly to achieve The purpose of quick valve closing;

When the valve is closed to the inflection point, the handle touches the straight rod and drives the straight rod to rotate around the center of the sphere. The straight rod drives the rotating body to rotate, and the connecting pipeline also rotates. They are all solid, so a branch of the hydraulic pipeline is cut off at this time, and the flow in the pipeline decreases; since the output speed of the hydraulic motor is determined by the flow through the hydraulic motor, the decrease in the output speed of the hydraulic motor causes the shaft to The rotation speed of the axial column decreases, and the closing speed of the valve connected with the axial column decreases, so as to realize the purpose of slow closing;

Due to the size of the straight rod, when the handle touches the straight rod and drives the straight rod to rotate at a small angle, it will be out of contact with the straight rod. At this time, the straight rod and the rotating body stop rotating, and the branch flowing through the sphere is always in an open circuit state.

The above-mentioned long-distance water supply pipeline accident quick valve closing device is also suitable for straight-line and regular opening of the valve:

Before opening the valve, activate the reversing valve to switch the high-pressure end and the low-pressure end, so that the flow direction of the connected hydraulic motor is completely opposite, and the output speed of the hydraulic motor is opposite, resulting in the opposite speed of the axial column. The valve connected to the axial column works The opposite action to the closing time realizes the opening of the valve; due to the constant flow in the pipeline, the output speed of the hydraulic motor also remains constant, resulting in a constant rotational speed of the axial column, and a constant closing speed of the valve connected to the axial column to achieve the purpose of straight-line opening .

Now the straight rod still deviates from the centerline at a certain angle, and due to the length, the straight rod does not touch the handle in any situation, so the branch flowing through the spheroid is always in an open circuit state.

When in use, the device of the present invention includes a hydraulic oil tank high pressure end, a low pressure end, a reversing valve, a hydraulic pipeline, a throttle valve, a ball, a communication pipeline, a rotating body, a connecting rod, a hydraulic motor, a handle, a valve, a straight rod, etc. . The oil flows out from the two branches at the high-pressure end of the hydraulic oil tank, and then merges into one pipeline to enter the hydraulic motor, flows out from the outlet of the hydraulic motor, and enters the low-pressure end through the pipeline.

By adjusting the throttle valve to control the flow in the hydraulic pipeline, and then control the output speed of the hydraulic motor, so as to control the closing speed of the valve.

The hydraulic pipeline is divided into two branches, a sphere is arranged in one of the branches, and a rotating body is installed in the sphere, wherein the rotating body is rotatable. There is a built-in connecting pipeline, and the rotating body is solid except for the connecting pipeline, and the lower part of the rotating body is fixedly connected with the connecting rod. The straight rod is fixedly connected with the connecting rod, and the straight rod can rotate horizontally around the center of the sphere and drive the rotating body to rotate, thereby driving the connecting pipeline to rotate.

There is a reversing valve on the right side of the hydraulic oil tank, which can switch the high-pressure end and low-pressure end of the hydraulic pipeline to control the flow direction of the oil in the hydraulic pipeline; the axial column of the hydraulic motor is fixedly connected with the valve stem of the valve, and the shaft The rotation of the column drives the opening and closing of the valve;

The invention principle and beneficial effects of the valve system will be described below by taking the emergency shut-off valve in the water delivery project as an example.

At present, the conventional valve closing method in water delivery projects is generally a conventional method of closing in a straight line, but the closing time of the conventional method is too long to achieve a quick response to the accident, so the valve system of the present invention adopts a fast closing method first and then a slow closing method. When the valve is closed quickly, the two branches of the high-pressure end of the hydraulic pipeline are connected. At this time, the total flow of the hydraulic pipeline is relatively large, the output speed of the hydraulic motor is relatively large, and the rotation speed of the axial column is relatively fast, which drives the valve to rotate rapidly to achieve The purpose of quick valve closing. When the valve is closed to the inflection point, the handle touches the straight rod and drives the straight rod to rotate around the center of the sphere. The straight rod drives the rotating body to rotate, and the connecting pipeline also rotates. Since the rotating body is solid except for the connecting pipeline, a branch of the hydraulic pipeline is cut off at this time, and the flow in the pipeline is reduced. Since the output speed of the hydraulic motor is controlled by the flow rate flowing through the hydraulic motor, the reduction of the output speed of the hydraulic motor results in a decrease in the speed of the axial column, and the closing speed of the valve connected to the axial column decreases to achieve the purpose of slow closing. Due to the size of the straight rod, when the handle touches the straight rod and drives the straight rod to rotate at a small angle, it will be out of contact with the straight rod. At this time, the straight rod and the rotating body stop rotating, and the branch flowing through the sphere is always in an open circuit state.

In general, the valve opening method in water delivery projects adopts the straight-line opening law. The valve system of the present invention can also realize the straight-line law opening of the valve. The flow direction is completely opposite, and the output speed of the hydraulic motor is opposite, resulting in the opposite rotation speed of the axial column, and the valve connected to the axial column performs the opposite action of closing to realize the valve opening. At this time, the straight rod still deviates from the center line by a certain angle. Due to the length, the straight rod does not touch the handle in any way, so the branch flowing through the sphere is always in an open circuit state, the flow in the pipeline is constant, and the output speed of the hydraulic motor is also constant. Keep constant, resulting in constant speed of the axial column, constant closing speed of the valve connected with the axial column, to achieve the purpose of straight-line opening.

Adjusting the relative position of the ball and the axial column can change the opening of the valve when the handle is in contact with the straight rod, thereby changing the position of the inflection point during the closing process.

Description of drawings:

Fig. 1 is the top view of the structure of the present invention when two branches of the hydraulic pipeline are in a connected state;

Fig. 2 is the front view of the structure of the present invention when the two branches of the hydraulic pipeline are in a connected state;

Fig. 3 is a partially enlarged view of the present invention when the valve is closed to the inflection point;

Figure 4 is a partially enlarged view of the present invention when the straight rod is out of contact with the handle;

Figure 5 is a partially enlarged view of the present invention when the valve is opened;

Fig. 6 is the process line of the relative opening of the valve with time in the embodiment of the present invention;

Fig. 7 is the process line of the pre-valve pressure changing with time in the embodiment of the present invention;

Fig. 8 is a process line of pipeline flow changing with time in an embodiment of the present invention.

The marks in the figure are: high pressure end 1 of hydraulic oil tank, low pressure end 2, reversing valve 3, hydraulic pipeline 4, ball 5, hydraulic motor 6, handle 7, straight rod 8, connecting pipeline 9, rotating body 10, connecting rod 11, axial column 12, valve 13, throttle valve 14.

detailed description:

Example:

The valve device used in the long-distance water delivery project of this embodiment is shown in Figure 1, Figure 2, Figure 3 and Figure 4. When the valve is closed, since the two branches connected to the high pressure end 1 of the hydraulic oil tank are in In the connected state, the total flow of the hydraulic pipeline 4 is larger, the output speed of the hydraulic motor 6 is larger, the rotation speed of the axial column 12 is larger, and the valve 13 is driven to rotate faster, so as to realize the purpose of fast valve closing. When the valve 13 is closed to the opening inflection point, the handle 7 touches the straight rod 8, and drives the straight rod 8 to rotate around the center of the sphere 5. Since the connecting rod 11 is fixed on the straight rod 8, the rotating body 10 is built into the sphere 5 and fixed. It is connected to the connecting rod 11, so the straight rod 8 drives the rotating body 10 to rotate, so the connecting pipeline 9 built in the rotating body 10 also rotates. Since the rotating body 10 is solid except for the connecting pipeline 9, at this time The branch flowing through the sphere 5 is cut off, the flow in the hydraulic pipeline 4 decreases, so the output speed of the hydraulic motor 6 decreases, resulting in a decrease in the speed of the axial column 12, and the valve 13 consolidated with the axial column 12 The closing speed is reduced to achieve the purpose of slow valve closing. Because of the length of the straight rod 8, the handle 7 drives the straight rod 8 to rotate and will be out of contact with the straight rod 8. At this moment, the rotating body 10 also stops rotating, and the branch flowing through the spheroid 5 is always in an open circuit state.

Generally, the opening of the valve in the water delivery project adopts the straight-line opening law, and the present invention can also realize the opening of the straight-line law. As shown in Figure 5, before the valve 13 is opened, the reversing valve 3 is started to switch the high-pressure end 1 and the low-pressure end 2 of the hydraulic oil tank. , so that the flow direction of the oil body in the hydraulic pipeline 4 is completely opposite, the flow direction of the oil body connected to the hydraulic motor 6 is completely opposite, and the output speed of the hydraulic motor 6 is reversed, resulting in the opposite speed of the axial column 12, which is consolidated with the axial column 12 The valve 13 performs the opposite action when it is closed, so that the valve 13 is opened. At this time, the straight rod 8 still deviates from the center line by a certain angle. Due to the length, the straight rod 8 does not touch the handle 7 in any situation, so the branch flowing through the sphere 5 is always in an open circuit state, and the flow in the hydraulic pipeline 4 is constant. The rotational speed output by the hydraulic motor 6 also remains constant, resulting in a constant rotational speed of the axial column 12, and a constant opening speed of the valve 13 consolidated with the axial column 12, thereby realizing the purpose of opening in a straight line.

A long-distance water transmission project, with a total length of 72.08km and a design flow rate of 12.67m ³ /s, consists of an inlet and outlet section, a trench-buried PCCP section, and a river-crossing pipe bridge section. The working pressure of the pipeline is 0.4-0.8MPa, and ancillary facilities such as townships, exhaust valves, manholes, vent valves, inspection valves and other auxiliary facilities are arranged along the line. When operating under design conditions, the upstream water level is 143.6m and the downstream water level is 128.39m. In this application example, the simulation of the transition process working condition is carried out for the conventional valve closing method and the valve closing method of the present invention, and the specific calculation results are shown in Fig. 6 to Fig. 8 .

As shown in Figure 6 and Figure 7, when the valve is closed by the conventional method, the valve closing time is 1500s, and the maximum pressure in front of the valve is 208.26m at this time; when the method of the present invention is used to close, the maximum pressure in front of the valve is 208.03m The maximum pressure in front of the valve under the conventional method is close to that, and the closing time of the valve is only 533s. As shown in Figure 8, when the valve is closed by the method of the present invention, the pipeline flow rate is quickly reduced to 0m ³ /s, which greatly speeds up the valve's accident response speed, saves a lot of water resources, and reduces accident losses.

Claims (8)

1. a kind of quick valve closer of distance water supply line accident, including hydraulic oil container, fluid pressure line and hydraulic motor, described Hydraulic motor be connected with valve it is characterised in that：Tie point and second branch road of parallel connection are had on described fluid pressure line, described Control valve with hydraulic motor linkage is in series with tie point.

2. the quick valve closer of distance water supply line accident according to claim 1 it is characterised in that：Described control valve There is spheroid, rotary body be installed in spheroid, a rotating body has connecting pipeline, is fixedly connected with the connecting rod below rotary body, Connecting rod is fixedly connected with straight-bar.

3. the quick valve closer of distance water supply line accident according to claim 1 it is characterised in that：Described hydraulic pressure horse The axial columns reaching are fixedly connected with the valve rod of valve, and described axial columns have handle, and described handle is overlapped with straight-bar.

4. the quick valve closer of distance water supply line accident according to claim 1 it is characterised in that：Described hydraulic tube It is in series with choke valve on the main road of road.

5. the quick valve closer of distance water supply line accident according to claim 1 it is characterised in that：Described hydraulic tube Reversal valve is provided with road.

6. the quick valve closer of distance water supply line accident according to claim 1 is it is characterised in that with axial columns be The center of circle, the centre of sphere is radius with the distance of axial columns, keeps straight-bar to point to axial columns, the position of horizontal adjustment ball, you can to change The aperture of valve when handle is contacted with straight-bar, thus arrange the position of flex point in closing process.

7. a kind of fast quick-closing valve method of distance water supply line accident it is characterised in that：

In rapid-closure damper, two branch roads of fluid pressure line high-pressure side all connect, and now fluid pressure line total flow is larger, hydraulic pressure The rotating speed of motor output is larger, and axial columns rotary speed is very fast, and band movable valve quickly rotates, and realizes the purpose of fast quick-closing valve；

After valve closing is to flex point, handle touches straight-bar, and drives straight-bar to rotate around the centre of sphere of spheroid, and straight-bar drives Rotary body rotates, and connecting pipeline also rotates, because rotary body is solid except connecting pipeline is with outer portion, so When fluid pressure line a branch road be cut off, flow in main road reduces；Because the output speed of hydraulic motor is by flowing through hydraulic pressure Determining, the rotating speed of hydraulic motor output reduces and leads to axial columns rotating speed to reduce the uninterrupted of motor, is connected with axial columns Valve closing speed reduces, and realizes the purpose of slowly closing；

Due to due to straight-bar size, handle is touched straight-bar and will be disengaged with straight-bar after driving straight-bar to make small angle rotation, Now straight-bar and rotary body stop the rotation, and the branch road flowing through spheroid is constantly in off state.

8. the fast quick-closing valve method of distance water supply line accident according to claim 7 it is characterised in that：

Before Open valve, start reversal valve, by high-pressure side with low-pressure end switching so that access hydraulic motor flux and flow direction is complete Entirely contrary, the rotating speed of hydraulic motor output is contrary, leads to axial columns rotating speed contrary, when the valve being connected with axial columns is made with closing Contrary action, realizes valve opening；

Now straight-bar still deviates horizontal line certain angle length, and due to due to length, straight-bar is being opened in operating mode not with handle Contact, therefore the branch road flowing through spheroid is constantly in off state.