On-line replacement auxiliary tool for valve positioner

Abstract

The utility model relates to the technical field of positioner replacement auxiliary tools, in particular to an on-line replacement auxiliary tool for a valve positioner, which comprises a three-way valve connected between a pneumatic actuating mechanism and the positioner and further comprises an air storage tank and a pressure reducing valve which are sequentially connected, and the pressure reducing valve is communicated with the three-way valve. The three-way valve is arranged between the positioner and the pneumatic actuating mechanism, and meanwhile, the gas storage tank is communicated with the three-way valve through the pressure reducing valve, so that when the positioner is overhauled and replaced, the gas signal output by the positioner can be cut off through the three-way valve, and a fault positioner is prevented from outputting a wrong gas signal; the influence on the air supply of the air storage tank can also be avoided; the pressure reducing valve adjusts the air pressure output by the air storage tank, and according to the opening degree of the valve, the three-way valve is used for providing an air signal for the pneumatic executing mechanism, so that it is guaranteed that the valve can be normally adjusted according to the production requirement, and therefore it is guaranteed that when the positioner is overhauled and replaced, the production continuity is not affected, and the actual requirement is met.

Description

Technical Field

[0001] The utility model relates to the technical field of positioner replacement auxiliary tools, and specifically relates to an online replacement auxiliary tool for a valve positioner. Background Technique

[0002] The valve positioner is one of the important accessories of the pneumatic control valve. For example, the Chinese invention patent application with the application number 202110492986.9 discloses a pneumatic valve positioner, which records: a pneumatic valve positioner is a device that receives weak electric signals such as 4-20 mA from a controller or a control system and conveys an air signal to a pneumatic actuator to control the valve position; it converts the DC current signal given by the control system into a gas signal for driving the control valve and controls the action of the control valve. At the same time, it feeds back according to the opening of the control valve so that the valve position can be correctly positioned according to the control signal output by the system.

[0003] During the actual operation process, when the positioner fails, the pneumatic actuator cannot control the opening of the valve according to the requirements, resulting in the valve opening suddenly fully or closing suddenly fully, affecting the actual operation of the equipment, that is, affecting the output and causing damage to the equipment, thus causing serious economic losses.

[0004] When overhauling and replacing the positioner, in order to avoid the misalignment of the valve opening, it is usually necessary to stop production, which also causes economic losses and cannot meet the actual production requirements. Content of the Utility Model

[0005] The purpose of the utility model is to provide an online replacement auxiliary tool for a valve positioner to solve the technical problem that the current replacement of the positioner requires shutdown.

[0006] To achieve the above purpose, the utility model provides the following technical solutions:

[0007] An online replacement auxiliary tool for a valve positioner includes a three-way valve connected between a pneumatic actuator and a positioner, and also includes an air storage tank and a pressure reducing valve connected in sequence, and the pressure reducing valve is communicated with the three-way valve.

[0008] Further limited, a check valve is connected between the pressure reducing valve and the three-way valve.

[0009] Further limited, the online replacement auxiliary tool for the valve positioner further includes a mobile trolley, the air storage tank is arranged in the mobile trolley, the air storage tank is connected with the mobile trolley, and the pressure reducing valve is located above the air storage tank.

[0010] Further limited, a support frame and a protective frame are arranged on the mobile trolley, the protective frame is arranged outside the support frame, the pressure reducing valve is located inside the protective frame, and the support frame is detachably connected with the air storage tank.

[0011] Further defined, the support frame is sleeved outside the gas storage tank.

[0012] Further defined, a buffer pad is arranged between the gas storage tank and the support frame.

[0013] Further defined, the gas storage tank is communicated with a pressure reducing valve through a first gas supply pipe, the pressure reducing valve is communicated with a three-way valve through a second gas supply pipe, and the one-way valve is arranged on the second gas supply pipe.

[0014] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0015] 1. A three-way valve is arranged between the positioner and the pneumatic actuator in the present utility model, and at the same time, the gas storage tank is communicated with the three-way valve through a pressure reducing valve. Thus, when the positioner is overhauled and replaced, the gas signal output by the positioner can be cut off through the three-way valve, avoiding the output of incorrect gas signals by the faulty positioner and also avoiding affecting the gas supply to the gas storage tank; the pressure reducing valve adjusts the air pressure output by the gas storage tank, and according to the opening degree of the valve, uses the three-way valve to provide a gas signal to the pneumatic actuator, so as to ensure that the valve can be normally adjusted according to production requirements. Furthermore, when the positioner is overhauled and replaced, the continuity of production is maintained without being affected, meeting the actual requirements.

[0016] 2. The present utility model is provided with a mobile cart to facilitate the movement of the gas storage tank. Thus, in actual use, if the positioner needs to be replaced, the gas storage tank is transported to the corresponding position through the mobile cart and connected to the three-way valve arranged between the positioner and the pneumatic actuator through the second gas supply pipe, making the online replacement of the positioner more convenient and fast, saving replacement time; when the positioner is replaced, through the adjustment of the pressure reducing valve and the three-way valve, the gas storage tank provides a stable gas signal, which is convenient for operation, reduces costs, and further meets the actual operation requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is the front view of the overall structure of the present utility model;

[0018] Figure 2 It is the connection schematic diagram of the present utility model with a single-acting actuator;

[0019] Figure 3 It is the connection schematic diagram of the present utility model with a double-acting actuator;

[0020] In the figure: 1 - gas storage tank; 2 - pressure reducing valve; 3 - one-way valve; 4 - three-way valve; 5 - mobile cart; 6 - support frame; 7 - protective frame; 8 - first gas supply pipe; 9 - second gas supply pipe; a - positioner; b - single-acting actuator; c - double-acting actuator. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0022] Referring to Figure 1 , this embodiment provides an auxiliary tool for online replacement of a valve positioner, which includes a gas storage tank 1, a pressure reducing valve 2, and a three-way valve 4 connected in sequence.

[0023] Among them, the three-way valve 4 needs to be installed on the pipeline between the positioner a and the pneumatic actuator. In order to avoid the need to separately add a three-way valve 4 when replacing the positioner a, increase the replacement time of the positioner a, and reduce the replacement efficiency, it is possible to choose to add a three-way valve to the main valve in advance during shutdown maintenance, and directly connect it to the pressure reducing valve 2 during use.

[0024] The air outlet end of the gas storage tank 1 is connected to the pressure reducing valve 2 through a first air supply pipe 8. The pressure reducing valve 2 is used to reduce the air pressure provided by the gas storage tank 1, so that the pneumatic actuator can perform the expected action, realizing the stable opening control of the valve during the online replacement of the positioner a to meet the actual production requirements.

[0025] The adjustment operator of the pressure reducing valve 2 can be controlled on-site according to actual needs.

[0026] The pressure reducing valve 2 is connected to the three-way valve 4 through a second air supply pipe 9. In order to improve the use safety of the gas storage tank 1, a check valve 3 or a non-return valve is selected to be provided on the second air supply pipe 9.

[0027] Both the first air supply pipe 8 and the second air supply pipe 9 can be selected to use 1 / 2 NPT metal braided pipes.

[0028] Furthermore, in order to facilitate moving the gas storage tank 1 to the corresponding position when the positioner a needs to be replaced, the auxiliary tool for online replacement of the valve positioner further includes a moving cart 5. The gas storage tank 1 is placed in the moving cart 5, which is convenient for the operator to carry the gas storage tank 1, saves the time for online replacement of the positioner a, improves the online replacement efficiency of the positioner a, and meets the actual use requirements.

[0029] Specifically, the moving cart 5 includes a cart board, moving wheels provided at the bottom of the cart board, a protective frame 7 provided on the cart board, a cart handle connected to the top of the protective frame 7, and a support frame 6 provided inside the protective frame 7.

[0030] Among them, the support frame 6 is connected to the protection frame 7. The support frame 6 is preferably detachably connected to the gas storage tank 1. Preferably, the support frame 6 is sleeved outside the gas storage tank 1 to protect the gas storage tank 1 during transportation, preventing the gas storage tank 1 from shaking when carried by the mobile trolley 5, which may increase the internal pressure, or preventing the gas storage tank 1 from colliding with the protection frame 7 and causing damage to the gas storage tank 1. Therefore, the support frame 6 effectively protects the gas storage tank 1, ensuring its safe and reliable use.

[0031] Furthermore, in order to improve the protection performance of the gas storage tank 1 and the support frame 6, a buffer pad is preferably provided between the gas storage tank 1 and the support frame 6. The buffer pad can be a rubber pad, further improving the service life and safety of the gas storage tank 1.

[0032] Further illustrate the use process of the on-line replacement auxiliary tool for the valve positioner provided by the present utility model.

[0033] When the pneumatic actuator is a single-acting actuator b:

[0034] Refer to Figure 2 , the input end of the positioner a is respectively connected to the control signal provided by the control system and the pressurized gas provided by the valve air source. The positioner a outputs air signals with different air pressures to the single-acting actuator b according to the demand for valve opening adjustment by the control signal.

[0035] The single-acting actuator b controls the valve to adjust the opening under the action of the air signal.

[0036] When the positioner a fails, it cannot effectively adjust the pressurized gas provided by the air source. Therefore, the output air signal is incorrect, which causes the single-acting actuator b not to execute according to the demand.

[0037] When replacing the faulty positioner a, use the mobile trolley 5 to carry the gas storage tank 1 to the corresponding position, and then connect the second air supply pipe 9 to the pre-set three-way valve 4.

[0038] Determine the air pressure adjusted and output by the pressure reducing valve 2 according to the demand. For example, the output air pressure is 0.8 kPa.

[0039] Subsequently, turn off the air supply to the positioner a by adjusting the three-way valve 4, and at the same time open the air supply of the second air supply pipe 9, so that the single-acting actuator b can control the valve to execute the corresponding opening according to the 0.8 kPa air signal provided by the gas storage tank 1, meeting the operation requirements, avoiding affecting the operation, and meeting the replacement requirements of the potentiometer a.

[0040] When the pneumatic actuator is a double-acting actuator c:

[0041] Refer to Figure 3, at this time, the input ends of the positioner a are respectively connected to the control signal and the valve air source. The positioner a controls the opening and closing at both ends of the double-acting actuator c according to the control signal, and the output ends of the positioner a are respectively connected to both ends of the double-acting actuator c.

[0042] A three-way valve 4 is pre-installed between both ends of the double-acting actuator c and the positioner a. When the positioner a fails, the operator moves the storage tank 1 to the position corresponding to the three-way valve 4 through the mobile cart 5. At this time, two mobile carts 5 are each required to carry a storage tank 1.

[0043] Subsequently, according to the control requirements, one end of the double-acting actuator c is supplied with air to open one corresponding end of the double-acting actuator c and close the other end, so as to realize the on-line replacement of the positioner of the double-acting actuator c. The operation is simple and meets the actual replacement requirements of the positioner.

[0044] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0045] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0046] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A valve positioner online replacement auxiliary tool, characterized in that: It comprises a three-way valve (4) connected between a pneumatic actuator and a positioner, and also comprises an air storage tank (1) and a pressure reducing valve (2) connected in sequence, wherein the pressure reducing valve (2) is communicated with the three-way valve (4).

2. The valve positioner online replacement auxiliary tool according to claim 1, characterized in that: A one-way valve (3) is connected between the pressure reducing valve (2) and the three-way valve (4).

3. The valve positioner online replacement auxiliary tool according to claim 2, characterized in that: The valve positioner online replacement auxiliary tool also includes a mobile cart (5), the gas storage tank (1) is arranged in the mobile cart (5), the gas storage tank (1) is connected to the mobile cart (5), and the pressure reducing valve (2) is located above the gas storage tank (1).

4. The valve positioner online replacement auxiliary tool according to claim 3, characterized in that: The mobile cart (5) is provided with a support frame (6) and a protection frame (7), wherein the protection frame (7) is arranged on the outside of the support frame (6), the pressure reducing valve (2) is located on the inside of the protection frame (7), and the support frame (6) is detachably connected to the gas storage tank (1).

5. The valve positioner online replacement auxiliary tool according to claim 4, characterized in that: The support frame (6) is sleeved on the outside of the gas storage tank (1).

6. The valve positioner online replacement auxiliary tool according to claim 5, characterized in that: A buffer pad is provided between the gas storage tank (1) and the support frame (6).

7. The valve positioner online replacement auxiliary tool according to claim 6, characterized in that: The gas storage tank (1) is connected to the pressure reducing valve (2) via a first gas supply pipe (8), the pressure reducing valve (2) is connected to the three-way valve (4) via a second gas supply pipe (9), and the one-way valve (3) is arranged on the second gas supply pipe (9).

Images