Method for adjusting the connecting rod of pneumatic regulating actuator

Abstract

A method for adjusting the position of a connecting rod of a pneumatically adjustable actuator. A common method on site is to manually adjust the connecting rod of the actuator, which is time-consuming and labor-intensive. At the same time, some actuators do not have a manually operated hand wheel and cannot be adjusted manually. The present invention comprises a pneumatic adjusting mechanism (6) and a valve (11). The pneumatic adjusting mechanism has a connecting rod (7), the lower part of the connecting rod has a connecting device (8), the valve has a valve stem (12), a valve packing (10) is installed on the valve stem, the pneumatic adjusting device is connected to an air intake pipe (4) through a quick-connect joint (5), a pneumatic proportional control valve (3) is installed on the air intake pipe, the air inlet of the pneumatic proportional control valve is connected to a pressure reducing valve (2) through a pipeline, and the pressure reducing valve is connected to a compressed air intake valve (1) through a pipeline; a valve position adjustment feedback device (9) is fixed on the valve packing. The present invention is used for adjusting the position of a connecting rod of a pneumatically adjustable actuator.

Description

Technical Field

[0001] The invention relates to a method for adjusting a connecting rod of a pneumatic regulating actuator. Background Art

[0002] In thermal systems where valves need to be reassembled after overhaul, or where the manufacturer assembles the actuator and valve, the pneumatic regulating actuator needs to accurately adjust the position of the actuator connecting rod when it is assembled with the valve stem. The common method on site is to manually adjust the actuator connecting rod, which is time-consuming and labor-intensive. At the same time, some actuators cancel the manual operation handwheel and cannot be adjusted manually. Summary of the invention

[0003] The purpose of the present invention is to solve the problems existing in the prior art and to provide a method for adjusting the connecting rod of a pneumatic regulating actuator.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A method for adjusting the connecting rod of a pneumatic regulating actuator, the method comprising the following steps:

[0006] (1) Close the compressed air inlet valve;

[0007] (2) Adjust the pressure reducing valve knob so that the compressed air pressure entering the pneumatic proportional control valve is 0;

[0008] (3) Use a 24VDC battery to power the pneumatic proportional control valve, connect the signal generator to the 4-20mA signal input terminal of the pneumatic proportional control valve, and adjust the input signal to 4mA;

[0009] (4) Attach the valve position adjustment feedback device to the upper part of the valve regulating packing, read the valve position adjustment feedback device number, and set it as X1;

[0010] (5) Open the compressed air inlet valve and adjust the pressure reducing valve knob to adjust the compressed air entering the pneumatic regulating mechanism to the appropriate pressure range;

[0011] (6) Use a signal generator to adjust the input signal to 20mA. At this time, the actuator connecting rod moves upward. After the actuator connecting rod stabilizes and stops, read the valve position adjustment feedback device digital and set it as X2.

[0012] (7) The relative travel L of the actuator connecting rod and the input signal current value I of the signal generator can be calculated through X1 and X2. The calculation formula of the current input signal current value I0 of the signal generator can be calculated as follows:

[0013] I=[16*L / (X2-X1)]+I0

[0014] The calculation formula can be used to adjust the input signal current value I of the signal generator to achieve the purpose of accurately adjusting the position of the actuator connecting rod.

[0015] The pneumatic regulating actuator connecting rod adjustment method, the pneumatic regulating mechanism has a connecting rod, the lower part of the connecting rod has a connecting device, the valve has a valve stem, the valve stem is installed with a valve packing, the pneumatic regulating device is connected to the air inlet pipe through a quick connector, the air inlet pipe is installed with a pneumatic proportional control valve, the air inlet of the pneumatic proportional control valve is connected to the pressure reducing valve through a pipeline, and the pressure reducing valve is connected to the compressed air inlet valve through a pipeline;

[0016] A valve position adjustment feedback device is fixed on the valve packing.

[0017] The pneumatic regulating actuator connecting rod position adjustment method, the valve position adjustment feedback device is a magnetic laser rangefinder, and the transmitting end of the magnetic laser rangefinder is aligned with the connecting device at the lower part of the connecting rod.

[0018] In the pneumatic regulating actuator connecting rod adjustment method, the signal input end of the pneumatic proportional control valve is connected to the signal generator.

[0019] Beneficial Effects

[0020] 1. The present invention can control the opening of the pneumatic actuator valve by adjusting the pressure of the compressed air entering the pneumatic actuator, so that the connecting rod moves up and down, and the distance between the transmitting end and the lower end of the connecting device is measured by a magnetic laser rangefinder to determine the action stroke of the pneumatic regulating mechanism connecting rod, so as to achieve the purpose of accurately adjusting the position of the pneumatic regulating mechanism connecting rod by adjusting the input signal current value I of the signal generator, so as to facilitate the assembly of the pneumatic regulating mechanism connecting rod and the valve stem. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG1 is a schematic diagram of the structure of the present invention;

[0022] In the figure: 1. Compressed air inlet valve; 2. Pressure reducing valve; 3. Pneumatic proportional control valve; 4. Inlet pipe; 5. Quick connector; 6. Pneumatic adjustment mechanism; 7. Connecting rod; 8. Connecting device; 9. Valve position adjustment feedback device; 10. Valve packing; 11. Valve; 12. Valve stem. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0024] 1 , a method for adjusting the connecting rod of a pneumatic regulating actuator is shown, and the method comprises the following steps:

[0025] (1) Close the compressed air inlet valve;

[0026] (2) Adjust the pressure reducing valve knob so that the compressed air pressure entering the pneumatic proportional control valve is 0;

[0027] (3) Use a 24VDC battery to power the pneumatic proportional control valve, connect the signal generator to the 4-20mA signal input terminal of the pneumatic proportional control valve, and adjust the input signal to 4mA;

[0028] (4) Attach the valve position adjustment feedback device to the upper part of the valve regulating packing, read the valve position adjustment feedback device number, and set it as X1;

[0029] (5) Open the compressed air inlet valve and adjust the pressure reducing valve knob to adjust the compressed air entering the pneumatic regulating mechanism to the appropriate pressure range;

[0030] (6) Use a signal generator to adjust the input signal to 20mA. At this time, the actuator connecting rod moves upward. After the actuator connecting rod stabilizes and stops, read the valve position adjustment feedback device digital and set it as X2.

[0031] (7) The relative travel L of the actuator connecting rod and the input signal current value I of the signal generator can be calculated through X1 and X2. The calculation formula of the current input signal current value I0 of the signal generator can be calculated as follows:

[0032] I=[16*L / (X2-X1)]+I0

[0033] The calculation formula can be used to adjust the input signal current value I of the signal generator to achieve the purpose of accurately adjusting the position of the actuator connecting rod.

[0034] A method for adjusting the position of a connecting rod of a pneumatic regulating actuator comprises: a pneumatic regulating mechanism 6 and a valve 11, wherein the pneumatic regulating mechanism is provided with a connecting rod 7, the lower part of the connecting rod is provided with a connecting device 8, the valve is provided with a valve stem 12, a valve packing 10 is installed on the valve stem, the pneumatic regulating device is connected to an air intake pipe 4 through a quick-connect joint 5, a pneumatic proportional control valve 3 is installed on the air intake pipe, the air inlet of the pneumatic proportional control valve is connected to a pressure reducing valve 2 through a pipeline, the pipeline is a stainless steel pipe, and the stroke size of the connecting rod of the actuator is precisely controlled by the cooperation of an external 4-20mA signal generator and a valve position adjustment feedback device, so as to facilitate the installation of the actuator and the regulating valve by the maintenance personnel, the pressure reducing valve is connected to a compressed air intake valve 1 through a pipeline, the pipeline is a stainless steel pipe, and the compressed air intake valve is connected to an on-site air source pipe joint at a production site through a hose to provide a working air source for the special tool.

[0035] A valve position adjustment feedback device 9 is fixed on the valve packing.

[0036] The valve position adjustment feedback device is a magnetic laser rangefinder, and the transmitting end of the magnetic laser rangefinder is aligned with the connecting device at the lower part of the connecting rod.

[0037] The signal input end of the pneumatic proportional control valve is connected to a signal generator, which is a 4-20mA signal generator matched with the pneumatic proportional control valve and is a commonly used device in the prior art.

Claims

1. A method for adjusting the connecting rod of a pneumatic regulating actuator, characterized by: The method comprises the following steps: (1) Close the compressed air inlet valve; (2) Adjust the pressure reducing valve knob so that the compressed air pressure entering the pneumatic proportional control valve is 0; (3) Use a 24VDC battery to power the pneumatic proportional control valve, connect the signal generator to the 4-20mA signal input terminal of the pneumatic proportional control valve, and adjust the input signal to 4mA; (4) Attach the valve position adjustment feedback device to the upper part of the valve packing, read the valve position adjustment feedback device number and set it as X1; (5) Open the compressed air inlet valve and adjust the pressure reducing valve knob to adjust the compressed air entering the pneumatic regulating mechanism to the appropriate pressure range; (6) Use the signal generator to adjust the input signal to 20mA. At this time, the connecting rod of the pneumatic adjustment mechanism moves upward. After the connecting rod of the pneumatic adjustment mechanism stabilizes and stops, read the valve position adjustment feedback device digital and set it as X2. (7) The relative stroke L of the connecting rod of the pneumatic adjustment mechanism and the input signal current value I of the signal generator and the current signal generator input signal current value I0 can be calculated through X1 and X2: I=[16*L / (X2-X1)]+I0 The calculation formula can be used to adjust the input signal current value I of the signal generator so as to achieve the purpose of accurately adjusting the position of the connecting rod of the pneumatic adjustment mechanism.

2. The method for adjusting the connecting rod of a pneumatic regulating actuator according to claim 1 is characterized in that: The pneumatic regulating mechanism is provided with a connecting rod, the lower part of the connecting rod is provided with a connecting device, the valve is provided with a valve stem, the valve stem is provided with a valve packing, the pneumatic regulating mechanism is connected to the air inlet pipe through a quick-connect joint, the air inlet pipe is provided with a pneumatic proportional control valve, the air inlet of the pneumatic proportional control valve is connected to the pressure reducing valve through a pipeline, and the pressure reducing valve is connected to the compressed air inlet valve through a pipeline; A valve position adjustment feedback device is fixed on the valve packing.

3. The method for adjusting the connecting rod of a pneumatic regulating actuator according to claim 2, characterized in that: The valve position adjustment feedback device is a magnetic laser rangefinder, and the transmitting end of the magnetic laser rangefinder is aligned with the connecting device at the lower part of the connecting rod.

4. The method for adjusting the connecting rod of a pneumatic regulating actuator according to claim 3 is characterized in that: The signal input end of the pneumatic proportional control valve is connected to the signal generator.

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