Double eccentric butterfly valve with a new body structure

Abstract

The present invention relates to a technical change in the body (2) structure of double eccentric butterfly valves (1) that is used in liquid and gas pipelines and that provides fluid control.

Description

[0001] DESCRIPTON

[0002] DOUBLE ECCENTRIC BUTTERFLY VALVE WITH A NEW BODY STRUCTURE

[0003] Technical Field

[0004] The present invention relates to a technical change in the body structure of double eccentric butterfly valves that is used in liquid and gas pipelines and that provides fluid control.

[0005] Prior Art

[0006] Butterfly valves are valves providing control of fluids that disable and enable the flow on the line by rotating 90° a flat throttle that is seated eccentrically or from its center. They have different driving systems such as hand wheel, electric, hydraulic or, pneumatic actuator. Butterfly valves are frequently preferred in the sector due to their advantages such as being light, having short assembly lengths, and enabling relatively free / comfortable passage of fluid. The shaft in the butterfly valve body bearings and the throttle, whose angle can be adjusted by means of said shaft, are the moving components of the valve that limit or prevent the flow. The throttle is fixed to the butterfly valve shaft, preventing it from coming out of the body and enabling it to operate in its current position. Due to the throttle structure in the state of the art, the flow does not move with a uniform velocity distribution and a constant acceleration. Therefore, vortices occur in the flow and cause vibration in the flow line. In this case, the resulting vortices create a risk of damage to the throttle and shaft and cause irregular flow.

[0007] In the state of the art, there is a circularly positioned protrusion inside the butterfly valve body in order to limit / cut off the flow of the fluid in the closed position in the flow line of the throttle fixed to the butterfly valve shaft. Said protrusion, which is located in a circular manner in the valve body in the flow line, operates together with the throttle to limit / cut off the passage of the fluid and provide sealing (Figure - 7). However, the valve diameter narrows at the position of this sealing protrusion on the butterfly valve body. In this case, the valve sealing diameter (DI) becomes smaller than the valve nominal diameter (DN) value (Figure - 8). Therefore, this protrusion in the internal structure of the body adversely affects the flow characteristics due to the narrowing experienced in the fluid passage area. Also, the potential risk of cavitation is higher and energy efficiency is significantly reduced as a result of this situation, which creates high pressure differences.

[0008] Butterfly valves in the state of the art have a standard design and are designed without considering the fluid passage properties. In addition thereto, its weight increases considerably and causes high opening / closing torques due to the larger actuator and larger gearbox thereof. As a result of these problems in the available butterfly valves;

[0009] -There is a decrease between valve nominal diameter (DN) and valve sealing diameter (DI),

[0010] -The flow characteristic is adversely affected due to the narrowing in the passage area,

[0011] -Vortices and vibrations occur in the flow caused by the throttle and body structure,

[0012] - High pressure differences occur,

[0013] - Potential cavitation risk is higher,

[0014] Energy efficiency reduces,

[0015] - The risk of damage to the valve is higher,

[0016] - Valve life is shorter.

[0017] Consequently, a new butterfly valve structure was necessitated to solve the above- mentioned problems existing in the state of the art and the inadequacy of the existing solutions necessitated making improvements in the related technical field.

[0018] Objects of the Invention

[0019] The object of the present invention is to obtain a body structure that provides fluid passage without removing the sealing protrusion and narrowing the diameter. Another object of the present invention is to obtain a lighter butterfly valve body with a new body structure with a minimized wall thickness, showing similar strength with the available butterfly valves.

[0020] Another object of the present invention is to minimize pressure loss and gain weight by means of the new body structure, which is different from the existing body structure used in butterfly valves.

[0021] Yet another object of the present invention is to provide a more regular flow by eliminating the vortices and vibrations occurring in the flow by means of the new body structure.

[0022] Thus,

[0023] -It is ensured that valve nominal diameter (DN) and valve sealing diameter (DI) are equal with the new body structure,

[0024] - It is ensured that the flow passage area is increased,

[0025] - Convenience for high flow rate is obtained,

[0026] Flow coefficient (Kv) is increased,

[0027] - Pressure losses are minimized,

[0028] - A more regular flow is provided,

[0029] - Cavitation risk is minimized,

[0030] - A Longer valve life is aimed.

[0031] Detailed Description of the Invention

[0032] The figures of the double eccentric butterfly valve that is used in liquid and gas pipelines and that provides fluid control are as follows:

[0033] Figure - 1 illustrates the view of the double eccentric butterfly valve with cambered body structure.

[0034] Figure - 2 illustrates the view of the double eccentric butterfly valve with cambered body structure and the throttle.

[0035] Figure - 3 illustrates the sectional view of the double eccentric butterfly valve with cambered body structure and the throttle. Figure - 4 illustrates the equalization of valve nominal diameter (DN) and valve sealing diameter (DI) in double eccentric butterfly valve sectional view.

[0036] Figure - 5 illustrates the sectional view of sealing elements in double eccentric butterfly valve with cambered body structure.

[0037] Figure - 6 illustrates the view of throttle movement in double eccentric butterfly valve.

[0038] Figure - 7 is a view illustrating that the valve nominal diameter (DN) is greater than the valve sealing diameter (DI) in the state of the art.

[0039] Figure - 8 is a view illustrating that the valve nominal diameter (DN) is greater than the valve sealing diameter (DI) in the state of the art.

[0040] Reference Numerals:

[0041] 1. Double Eccentric Butterfly Valve

[0042] 2. Body

[0043] 3. Throttle

[0044] 4. Shaft

[0045] 5. Sealing Rubber

[0046] 6. Compression Ring

[0047] DN: Valve Nominal Diameter

[0048] DI: Valve Sealing Diameter

[0049] D2: Body Diameter

[0050] Figure - 1 shows the double eccentric butterfly valve (1) that is used in liquid and gas pipelines and that provides fluid control. The double eccentric butterfly valve (1) in its most general form consists of the body (2), the throttle (3), and the shafts (4).

[0051] Double eccentric butterfly valve (1) in cylindrical form has a throttle (3) in order to provide fluid control in liquid and gas pipelines. The diameter of the throttle (3), which is in a circular form, has a smaller diameter than the valve nominal diameter (DN) and it is located inside the double eccentric butterfly valve (1). The connection of the throttle (3) is provided with the aid of at least two shafts (4) placed on the bearings opened to the right and left parts of the double eccentric butterfly valve (1) such that it is perpendicular to the center of the double eccentric butterfly valve (1). Shafts (4) ensure that the throttle (3) is attached to the double eccentric butterfly valve (1). The throttle (3) is prevented from coming out of the body (2) and it is provided to operate angularly in its current position by means of the shafts (4). The throttle (3), which is in a fixed position, rotates 90° around its own axis by means of the drive of the shafts (4), and allows for providing fluid control (Figure - 2, Figure - 3).

[0052] When the throttle (3) is positioned at right angles to the pipeline, liquid and / or gas flow is stopped. As soon as the throttle (3) is fully seated on the body (2) seating surface, it makes tight contact with the seating surface and provides sealing. The sealing rubber (5) is placed on the double eccentric butterfly valve (1) in order to prevent fluid leakage from the throttle (3) in a closed position. The sealing rubber (5) is attached to the throttle (3) with the pressure ring (6). The sealing rubber (5) and the pressure ring (6) move together with the throttle (3) (Figure - 6). The section of the sealing rubber (5) is located between the pressure ring (6) and the throttle (3), as seen in Figure-5.

[0053] In the new boy design, the valve sealing diameter (DI) is enlarged not to be smaller than the valve nominal diameter (DN) in order to eliminate the negative effects of diameter reduction in conventional butterfly valves described in the state of the art. (Figure - 4). As a result of this improvement, the diameter of the throttle (3) is enlarged in order to provide the same sealing performance. A chamber with a body diameter (D2) at least equal to the nominal valve diameter (DN) is formed in the body (2) due to the double eccentric structure of the double eccentric butterfly valve (1), in order for the clapper (3) can move 90° inside the body (2) without contacting the inside diameter of the body (2) (Figure - 4). This chamber can be outwardly cambered or outwardly angular. Thus, the area in which the throttle (3) moves, and thus the flow area, is increased with the increasing diameter of the throttle (3). The body (2) may have a convex, triangular, cambered, etc. form in order for the throttle (3) to move inside the body (2) without contacting the inner diameter of the body (2). In order for the throttle (3) to be locked in the double eccentric butterfly valve (1), the flow is prevented by sitting on the body (2) surface that has a cambered / triangular structure, and whose angle decreases while the throttle (3) is closed. Thus, the flow area is increased by eliminating the sealing area existing in the state of the art. It is possible to observe the movement detail of the throttle (3) inside the body (2) in detail in Figure 6. In order to avoid the problems existing in the state of the art, a body (2) with a larger diameter than the valve nominal diameter is obtained in the double eccentric butterfly valve (1) by making the valve sealing diameter (DI) at least equal to the valve nominal diameter (DN). The flow passage area has been increased compared to the butterfly valve used in the state of the art by means of these developments.

[0054] In this case, it was calculated that the flow passage area was increased by at least 10% compared to the butterfly valve used in the state of the art, and the flow coefficient (Kv) was increased by at least 50% in line with the 3D computational fluid dynamics analysis. With the valve nominal diameter (DN) and valve sealing diameter (DI) being equal, the problems existing in the state of the art are eliminated and an improved double eccentric butterfly valve (1) is obtained.

Claims

CLAIMS1. A double eccentric butterfly valve (1) that is used in liquid and gas pipelines and that provides fluid control, characterized in that, the body diameter (D2) of the body (2) in which the throttle (3) is seated on said double eccentric butterfly valve (1) is greater or equal to the valve nominal diameter (DN), and said throttle (3) sits on the surface of the body (2) with a diameter larger than said valve nominal diameter (DN) when said double eccentric butterfly valve (1) is in the closed position in order to prevent the flow inside said double eccentric butterfly valve (1).

2. A double eccentric butterfly valve (1) that is used in liquid and gas pipelines and that provides fluid control according to Claim 1, characterized in that, said body (2) has a cambered structure.

3. A double eccentric butterfly valve (1) that is used in liquid and gas pipelines and that provides fluid control according to Claim 1, characterized in that, said body (2) has an angular structure.

4. A double eccentric butterfly valve (1) that is used in liquid and gas pipelines and that provides fluid control according to Claim 1, characterized in that, said body (2) has a triangular structure.

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