Sealing mechanism for valve rod of center line-type butterfly valve

Abstract

The utility model relates to the field of water treatment, in particular to a sealing mechanism for a valve rod of a center line-type butterfly valve, which is arranged between a valve body and an actuating mechanism, the valve body is fixedly connected with the actuating mechanism through a bolt, the valve rod is arranged at the upper end of the valve body, and the sealing mechanism comprises a lower sealing ring, a pressing block, a packing layer and a gland, the valve rod penetrates through the stepped channel and then is connected with the executing mechanism, the lower sealing ring is arranged at the bottom of the stepped channel, a groove with a T-shaped section is formed in the upper end of the lower sealing ring, the pressing block is arranged in the groove, and the gland is arranged on the upper portion of the stepped channel and located at the lower end of the executing mechanism. The packing layer is arranged between the gland and the lower sealing ring and in the groove, multi-level pressurization on the packing layer and the sealing ring is achieved through the joint force of the executing mechanism and the valve rod, and therefore the sealing performance is improved, and medium leakage is prevented.

Description

Technical Field

[0001] The utility model relates to the field of water treatment, in particular to a sealing mechanism for a valve stem of a centerline butterfly valve. Background Art

[0002] In water treatment systems, as the volume of treated water continues to expand, the number of filter elements and automatic valves continues to increase, resulting in a significant investment in valves. For clean water media with small diameters, centerline butterfly valves are generally used. Currently, virtually all valve manufacturers design a valve body directly connected to the actuator, without a stem seal. In reclaimed water reuse systems, the medium often contains particulate matter and other impurities. This can cause water to leak from the junction of the valve stem and actuator after prolonged valve operation. In severe cases, water can directly enter the actuator, then flow through its cylinder to the actuators of other valves, affecting the stable operation of the entire system.

[0003] Therefore, in order to solve the deficiencies in the prior art, a sealing mechanism for a centerline butterfly valve stem with a simple structure needs to be designed. Utility Model Content

[0004] In order to solve the problems of the prior art, the utility model provides a sealing mechanism for a valve stem of a centerline butterfly valve.

[0005] The purpose of the utility model can be achieved through the following technical solutions: a sealing mechanism for a center line butterfly valve stem, which is arranged between the valve body and the actuator, and the valve body and the actuator are fixedly connected by bolts. A valve stem is provided at the upper end of the valve body, including: a lower sealing ring, a pressure block, a packing layer and a pressure cover. A stepped channel is provided on the top of the valve body, and the valve stem is connected to the actuator after passing through the stepped channel. The lower sealing ring is arranged at the bottom of the stepped channel, and a groove with a T-shaped cross-section is provided at the upper end of the lower sealing ring. The pressure block is arranged in the groove, and the pressure cover is arranged at the upper part of the stepped channel and at the lower end of the actuator. The packing layer is arranged between the pressure cover and the lower sealing ring and in the groove.

[0006] A further improvement is that the stepped channel includes an upper channel, a middle channel and a lower channel which are connected downward in sequence, the diameter of the upper channel is larger than that of the middle channel, the diameter of the lower channel is larger than that of the middle channel, the lower sealing ring is arranged in the lower channel, the pressure block and the packing layer are arranged in the middle channel, and the pressure cover is arranged in the upper channel.

[0007] As a further improvement, an upper sealing ring is provided at the upper end of the upper cover, and the upper sealing ring is located at the lower end of the actuator.

[0008] As a further improvement, the material of the filler layer is graphite material.

[0009] As a further improvement, the material of the packing layer is polytetrafluoroethylene.

[0010] Compared with the prior art, the sealing mechanism of the centerline butterfly valve stem of the utility model has the following beneficial effects:

[0011] Through structural design, the engagement force between the actuator and the valve stem is utilized to achieve multi-level pressurization of the packing layer and the sealing ring, thereby improving the sealing performance and preventing medium leakage. The design is simple and easy to install and maintain, without the need for complex mechanical accessories or special tools. The packing layer material is easy to replace, and different materials such as graphite or polytetrafluoroethylene can be selected according to the corrosiveness and pressure of the medium to adapt to different working environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the structure of the utility model

[0013] Figure 2 This is a structural diagram of a partially enlarged view of the utility model

[0014] In the figure, 1-lower sealing ring, 11-groove, 2-pressure block, 3-packing layer, 4-pressure cover, 5-upper sealing ring, 6-valve body, 61-step channel, 611-upper channel, 612-middle channel, 613-lower channel, 7-actuator, 8-bolt, 9-valve stem. DETAILED DESCRIPTION

[0015] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0016] In the description of this utility model, it should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections. Those skilled in the art will understand the specific meanings of these terms in this utility model based on the specific circumstances.

[0017] Below with reference to the embodiment and the attached Figures 1-2 , the technical solution of the utility model is further elaborated.

[0018] Example 1

[0019] A sealing mechanism for a centerline butterfly valve stem is arranged between a valve body 6 and an actuator 7. The valve body 6 and the actuator 7 are fixedly connected by bolts 8. A valve stem 9 is provided at the upper end of the valve body 6, comprising: a lower sealing ring 1, a pressure block 2, a packing layer 3 and a pressure cover 4. A stepped channel 61 is provided at the top of the valve body 6. The valve stem 9 is connected to the actuator 7 after passing through the stepped channel 61. The lower sealing ring 1 is arranged at the bottom of the stepped channel 61. A groove 11 with a T-shaped cross-section is provided at the upper end of the lower sealing ring 1. The pressure block 2 is arranged in the groove 11. The pressure cover 4 is arranged at the upper part of the stepped channel 61 and is located at the lower end of the actuator 7. The packing layer 3 is arranged between the pressure cover 4 and the lower sealing ring 1 and in the groove 11.

[0020] like Figures 1 and 2 As shown, the working principle of the present invention is as follows: through the connection of bolts 8, the self-engagement force of the actuator 7 and the valve stem 9 is utilized to clamp the gland 4 located in the stepped channel 61, which is about 2 mm higher than the top. The gland 4 presses down the packing layer 3, which presses down the pressure block 2. The pressure block 2 presses down the lower sealing ring 1 along the groove 11. The inner side of the lower sealing ring 1 is pushed inward to press against the valve stem 9, while the outer side of the lower sealing ring 1 is pushed outward to press against the inner wall of the stepped channel 61, thereby improving the sealing performance. At the same time, the packing layer 3 is pressurized to fill the remaining space, thereby improving the sealing performance of the valve stem and ensuring that the medium will not leak after the valve stem is worn. In addition, the graphite packing is low in cost and easy to replace. Ordinary glands are used, and no additional special glands are required. The material and thickness of the packing layer 3 can be selected according to the corrosiveness and pressure of the medium. At the same time, this structure basically does not install other mechanical accessories on the valve, which has no effect on the overall structure of the valve. It has the characteristics of simple gas path and easy operation, ensuring the stable operation of the entire water treatment system and avoiding system failures caused by valve problems.

[0021] As a further preferred embodiment, the stepped channel 61 includes an upper channel 611, a middle channel 612, and a lower channel 613 that are sequentially connected downward. The diameter of the upper channel 611 is larger than that of the middle channel 612, and the diameter of the lower channel 613 is larger than that of the middle channel 612. The lower sealing ring 1 is disposed in the lower channel 613, the pressing block 2 and the packing layer 3 are disposed in the middle channel 612, and the gland 4 is disposed in the upper channel 611. When the pressing block 2 presses the lower sealing ring 1 downward along the groove 11, the outer side of the lower sealing ring 1 is pushed and squeezed outward into the lower channel 613, preventing the lower sealing ring 1 from moving upward into the middle channel 612. This stabilizes the position of the lower sealing ring 1, improves the sealing performance of the valve stem, and reduces friction between the lower sealing ring 1 and the valve stem.

[0022] As a further preferred embodiment, an upper sealing ring 5 is provided at the upper end of the upper cover 4, and the upper sealing ring 5 is located at the lower end of the actuator 7. The upper sealing ring 5 can further improve the overall sealing performance. At the same time, in the process of compacting the packing layer, the elastic characteristics of the upper sealing ring 5 can make the packing layer 3 higher than the upper end surface of the middle channel 612. The pressure cover 4 can compress the upper sealing ring 5 upward to make its overall height equal to that inside the upper channel 611, thereby ensuring stable compaction.

[0023] As a further preferred embodiment, the material of the packing layer 3 is graphite material. Graphite material has good self-lubrication, high temperature resistance, corrosion resistance and chemical stability, reduces the friction of the valve stem and improves the stability of use.

[0024] As a further preferred embodiment, the material of the packing layer 3 is polytetrafluoroethylene. Polytetrafluoroethylene has a very low friction coefficient of approximately 0.05 to 0.1, which makes it produce almost no friction during sliding or rolling contact, thereby reducing friction on the valve stem and further reducing the friction gap between the valve stem and the valve body.

[0025] The above describes in detail the preferred embodiments of the present invention. It should be understood that those skilled in the art can make numerous modifications and variations based on the concepts of the present invention without inventive effort. Therefore, any technical solutions that can be derived by those skilled in the art based on the concepts of the present invention through logical analysis, reasoning, or limited experimentation based on the existing technology should be within the scope of protection defined by the claims.

Claims

1. A sealing mechanism for a centerline butterfly valve stem, which is arranged between a valve body and an actuator, wherein the valve body and the actuator are fixedly connected by bolts, and a valve stem is provided at the upper end of the valve body, characterized in that: include: A lower sealing ring, a pressure block, a packing layer and a pressure cover. A stepped channel is provided on the top of the valve body. The valve stem is connected to the actuator after passing through the stepped channel. The lower sealing ring is arranged at the bottom of the stepped channel. A groove with a T-shaped cross-section is provided at the upper end of the lower sealing ring. The pressure block is arranged in the groove. The pressure cover is arranged at the upper part of the stepped channel and at the lower end of the actuator. The packing layer is arranged between the pressure cover and the lower sealing ring and in the groove.

2. The sealing mechanism of a centerline butterfly valve stem according to claim 1, characterized in that: The stepped channel includes an upper channel, a middle channel and a lower channel which are connected downward in sequence. The diameter of the upper channel is larger than that of the middle channel, the diameter of the lower channel is larger than that of the middle channel, the lower sealing ring is arranged in the lower channel, the pressure block and the packing layer are arranged in the middle channel, and the pressure cover is arranged in the upper channel.

3. The sealing mechanism of a centerline butterfly valve stem according to claim 1, characterized in that: An upper sealing ring is provided at the upper end of the upper cover, and the upper sealing ring is located at the lower end of the actuator.

4. The sealing mechanism of a centerline butterfly valve stem according to claim 1, characterized in that: The material of the filler layer is graphite material.

5. The sealing mechanism of a centerline butterfly valve stem according to claim 1, characterized in that: The material of the packing layer is polytetrafluoroethylene.

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