A built-in full-isolation membrane balanced electric actuator and adjustment method

Abstract

An internal fully-isolated diaphragm balanced electric actuator built into the valve includes: a pressure balancing diaphragm, an actuator housing, a balancing filling fluid, and an electric actuator assembly; the over-pressure balancing diaphragm and the balancing filling fluid offset the pressure balance inside and outside the actuator, effectively protecting the internal structure of the actuator, greatly reducing the shell strength of the actuator and related sealing requirements, improving the integration of the electric valve, and enabling the actuator to be reliably used in high-pressure and ultra-high-pressure environments.

Description

Technical Field

[0001] The present application relates to the related field of an electric control actuator built into a valve in a valve actuator, and is a built-in full-isolation diaphragm balanced electric actuator used to be built into a valve. Background Art

[0002] In today's situation where automatic control has become the main control method, the electric control actuator of the electric valve has become an essential valve control component. However, since our existing electric control actuators cannot come into direct contact with liquids, a large number of dynamic seals are used for leakage prevention and isolation. However, the friction resistance of the dynamic seal is proportional to its sealing performance, that is, to achieve high sealing performance, it is inevitable to be accompanied by huge friction resistance. This dynamic seal structure directly reduces the service life of the valve, while reducing the efficiency of the actuator and increasing power consumption.

[0003] In order to reduce the actuator loss, improve the actuator efficiency, increase the valve life and improve the compactness of the electric valve, we hope to place the actuator directly inside the valve. However, due to the extremely high liquid pressure in the high-pressure valve, the electric actuator completely placed inside the valve will face the huge pressure of the liquid, which requires higher strength and sealing of the valve actuator shell. At the same time, when the actuator is in motion, its moving components will also be hindered by the liquid pressure. Therefore, the industry has been unable to reliably solve this problem, which has also limited the development of valves with built-in actuator structures. Summary of the invention

[0004] In order to solve the above-mentioned problems, we have filed this application, the purpose of which is to provide a built-in full-isolation diaphragm balanced electric actuator that is completely installed inside the electric valve and fully placed in the liquid flowing in the valve. Based on this purpose, another purpose of this application is to propose a method for adjusting the built-in full-isolation diaphragm balanced electric actuator.

[0005] The purpose of this application is described as follows: A built-in fully isolated diaphragm balanced electric actuator is mainly composed of a shell, a pressure balancing diaphragm, a balancing filling liquid and an internal electric actuator assembly. The shell and the pressure balancing diaphragm together form a closed cavity, the electric actuator assembly is placed in the cavity, and the cavity is filled with a balancing filling liquid.

[0006] The pressure balancing membrane of the above-mentioned built-in full isolation membrane balanced electric actuator is installed on the actuator housing, one side of which is connected to the inside of the actuator and the other side is connected to the space inside the valve. The pressure balancing membrane has the characteristic of elastic deformation, and it can be an elastic diaphragm or other shapes. The elastic deformation of the pressure balancing membrane should be greater than the deformation of the balancing filling fluid in the cavity.

[0007] The electric actuator assembly of the above-mentioned built-in full-isolation diaphragm balanced electric actuator can be any combination of an electric motor, a solenoid valve, a mechanical actuator and a circuit control part.

[0008] Based on the above, the best way to combine the housing and the pressure balance membrane of a built-in full isolation membrane balanced electric actuator is to use a static seal method. The housing and the pressure balance membrane together form a closed cavity, and this closed cavity does not use any dynamic sealing structure with the outside. This provides a stable and unified working environment for the motor, solenoid valve, mechanical actuator and circuit control part in the actuator, thereby improving the stability and consistency of the actuator.

[0009] Based on the above-mentioned built-in full isolation diaphragm balanced electric actuator, it can adopt a degraded form, which is suitable for valve applications in the form of homogeneous liquid media, that is, the balancing liquid and the liquid passing through the valve are homogeneous liquids. In this case, a dynamic sealing structure can be used at the output shaft to reduce the sealing requirements of the dynamic seal of the equipment under high pressure.

[0010] The balancing filling liquid of the above-mentioned built-in full-isolation diaphragm balanced electric actuator can be any liquid with good fluidity. The balancing filling liquid should have certain electrical insulation and lubricity.

[0011] Based on the above, a built-in fully isolated diaphragm balanced electric actuator adopts a balancing filling liquid with electrical insulation, which can provide good heat dissipation for the heating components in the above actuator, thereby improving the stability of the actuator.

[0012] Based on the above-mentioned built-in full-isolation diaphragm balanced electric actuator, a lubricating balancing filling liquid is used, which can provide sufficient lubrication for the moving components in the above-mentioned actuator, thereby increasing the life of the mechanical parts.

[0013] Based on the above, a built-in fully-isolated diaphragm balanced electric actuator adopts a pressure balance diaphragm with elastic deformation characteristics. The deformation of the pressure balance diaphragm is much larger than the compression deformation of the internal space of the actuator filled with the balance filling liquid. In this way, the pressure outside the actuator can be fully and evenly applied to the internal balance filling liquid, so as to achieve the purpose of balancing the internal and external pressures. In this way, the strength and pressure resistance requirements of the shell and related seals are reduced, and the actuator can be adapted to various working conditions under extreme pressures, especially valves working under high pressure and ultra-high pressure conditions.

[0014] The adjustment method of a built-in full-isolation diaphragm balanced electric actuator is described as follows: When there is high liquid pressure in the valve, the pressure outside the actuator is transmitted to the balanced filling liquid through the pressure balance diaphragm, and the balanced filling liquid evenly distributes the pressure inside the actuator. Based on the extremely low compressibility and pressure transmission characteristics of the liquid, the pressure inside and outside the actuator is balanced with minimal deformation. This means that the pressure of the liquid inside the valve on the actuator housing and the pressure balance diaphragm will be offset, which greatly reduces the shell strength of the actuator and related sealing requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The linear valve actuator of Example 1 is shown in the figure.

[0016] Figure 2 The figure shows a rotary valve actuator according to a second embodiment.

[0017] Figure 3 The figure shows a magnetic coupling type valve actuator according to a third embodiment.

[0018] Legend: 1. Pressure balancing membrane; 2. Actuator housing; 3. Balancing filling fluid; 4. Liquid flowing in the valve; 5. Electric actuator assembly; 6. Valve body; 7. Drive shaft; 8. Linear slider; 9. Valve core; 10. Magnetic coupler. DETAILED DESCRIPTION

[0019] The present application is not limited by the following embodiments, and the specific implementation method can be determined according to the technical solution of the present application and actual conditions.

[0020] like Figure 1 , Figure 2 , Figure 3 As shown, a built-in full isolation diaphragm balanced electric actuator includes a pressure balancing diaphragm 1, an actuator housing 2, a balancing filling liquid 3, and an electric actuator assembly 5. The pressure balancing diaphragm 1 is mounted on the actuator housing 2, and together with the actuator housing 2, forms an actuator inner space. The electric actuator assembly 5 is placed therein, and the actuator inner space is then filled with the balancing filling liquid 3.

[0021] The pressure balancing membrane 1 can be an elastic membrane made of any elastic material or other elastic shapes. The elastic deformation of the pressure balancing membrane should be greater than the deformation of the balancing filling fluid in the cavity.

[0022] The above-mentioned balancing filling liquid 3 can be any liquid with good fluidity, and it is best if it has electrical insulation and lubricity.

[0023] The electric actuator assembly 5 may include various existing valve actuator drive components, which may be any combination of electrical components such as solenoid valves, motors, and circuit boards, and mechanical components such as linear screws, linear guide rails, rotating shafts, and gearboxes.

[0024] Example 1: Figure 1 As shown, the electric actuator assembly 5 of a built-in full-isolation diaphragm balanced electric actuator is an existing valve actuator drive structure, specifically in embodiment 1, it includes a drive shaft 7 and a linear slider 8.

[0025] The built-in fully-isolated diaphragm balanced electric actuator described in Example 1 is installed inside the valve body 6, the linear slider 8 of the electric actuator assembly 5 is connected to the valve core 9, the drive shaft 7 drives the linear slider 8 to make a linear motion, and the linear slider 8 drives the valve core 9 to play the role of opening and closing the valve. When the pressure of the liquid 4 flowing in the valve body 6 changes or the movement of the drive slider 8 causes the space in the actuator to change, resulting in a change in the pressure inside and outside the actuator, the pressure balance membrane 1 is deformed by this pressure change, and the pressure is transmitted to the inside of the actuator through the balance filling liquid 3, achieving a balance between the internal and external pressures, while protecting the actuator.

[0026] Example 2: Figure 2 As shown, the electric actuator assembly 5 of a built-in full-isolation diaphragm balanced electric actuator is an existing valve actuator drive structure, and specifically in Example 2, it includes a drive shaft 7 and a magnetic coupler 10.

[0027] A built-in fully-isolated diaphragm balanced electric actuator described in Example 2 is installed inside the valve body 6, and the drive shaft 7 of the electric actuator assembly 5 is connected to the magnetic coupler 10. The magnetic coupler 10 is coupled to the valve core 9, and the drive shaft 7 rotates the valve core 9 through the magnetic coupler 10 to open and close the valve. When the pressure change of the liquid 4 flowing in the valve of the valve body 6 causes the pressure inside and outside the actuator to change, the pressure balance membrane 1 is deformed by this pressure change, and the pressure is transmitted to the inside of the actuator through the balance filling liquid 3, achieving internal and external pressure balance, thereby protecting the actuator. Therefore, the actuator housing can be designed to be thin enough, thereby improving the coupling torque of the magnetic coupler 10 and increasing the efficiency of the magnetic coupling actuator.

[0028] Example 3: Figure 3As shown, it is a degraded built-in full isolation diaphragm balanced electric actuator, which is limited to the application of the same liquid medium, that is, the balancing liquid and the liquid passing through the valve are liquids of the same nature. The electric actuator assembly 5 is an existing valve actuator drive structure, and specifically includes a drive shaft 7 in Example 3. The built-in full isolation diaphragm balanced electric actuator is installed inside the valve body 6, and the drive shaft 7 of the electric actuator assembly 5 is connected to the valve core 9. It adopts a dynamic sealing structure at the output shaft 7, and rotates the valve core 9 by the drive shaft 7 to play the role of opening and closing the valve. When the pressure change of the liquid 4 flowing in the valve of the valve body 6 causes the pressure inside and outside the actuator to change, the pressure balancing diaphragm 1 is deformed by this pressure change, and the pressure is transmitted to the inside of the actuator through the balancing filling liquid 3, achieving internal and external pressure balance, thereby protecting the actuator from damage caused by the pressure change of the liquid 4 flowing in the valve, and at the same time reducing the sealing requirements of the dynamic seal.

[0029] The above technical features constitute the best implementation example of the present application, which has strong adaptability and best implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the needs of different situations.

Claims

1. A built-in fully isolated diaphragm balanced electric actuator, characterized in that: It consists of a shell, a pressure balance membrane, a balance filling liquid and an internal electric actuator; the shell and the pressure balance membrane together form a closed cavity, the electric actuator is placed in this cavity, and the cavity is filled with a balance filling liquid, and there is no dynamic sealing structure between this closed cavity and the outside; The pressure balance membrane has the characteristic of elastic deformation, and its elastic deformation is greater than the deformation of the balance filling fluid in the cavity; The shell and the pressure balance membrane are combined in a static sealing manner.

2. A built-in fully-isolated diaphragm balanced electric actuator according to claim 1, characterized in that: The pressure balancing membrane is installed on the actuator housing, one side of which is connected to the inside of the actuator and the other side is connected to the space inside the valve.

3. A built-in full-isolation diaphragm balanced electric actuator according to claim 1, characterized in that: The above-mentioned balancing filling liquid is a liquid with good fluidity.

4. A built-in full-isolation diaphragm balanced electric actuator according to claim 1 or 3, characterized in that: The above-mentioned balancing filling liquid is a liquid having lubricating properties.

5. A built-in full-isolation diaphragm balanced electric actuator according to claim 1 or 3, characterized in that: The above-mentioned balancing filling liquid is an electrically insulating liquid.

6. A built-in fully-isolated diaphragm balanced electric actuator according to claim 1, characterized in that: The electric actuator assembly mentioned above can be any combination of a solenoid valve, a motor, a circuit board, a linear screw, a linear guide rail, a rotating shaft and a gearbox.

7. A method for adjusting a built-in fully-isolated diaphragm balanced electric actuator, characterized in that: When using a built-in fully-isolated diaphragm balanced electric actuator as described in claim 1, the external pressure of the shell is transmitted to the balancing filling liquid through the pressure balancing diaphragm, and the balancing filling liquid evenly distributes the pressure to the inside of the actuator. Based on the extremely low compressibility and pressure transmission characteristics of the liquid, the deformation of the pressure balancing diaphragm is used to balance the internal and external pressures of the actuator.

Images