Secondary sealing structure of flat gate valve

Abstract

The utility model provides a flat gate valve secondary sealing structure which comprises a valve body, a valve plate, a valve rod and a primary sealing device, the valve plate is arranged in the valve body, the valve rod is connected with the top of the valve plate, the valve body is connected with a sealing seat, the primary sealing device is arranged in the sealing seat, a secondary sealing device is further arranged in the sealing seat, and the secondary sealing device is connected with the valve plate. The second-stage sealing device is arranged above the first-stage sealing device, and the valve rod penetrates out of the sealing seat and then is connected with an early warning mechanism. According to the utility model, the secondary sealing device is additionally arranged, so that the sealing leakage period of the gate valve is prolonged, meanwhile, when the secondary sealing device leaks, the secondary sealing device can be taken out for replacement, and the technical problem that the gate valve seal cannot be replaced when a flowing medium in a pipeline cannot be completely discharged is solved. According to the second-stage sealing structure of the flat gate valve, the second-stage sealing device is additionally arranged, the sealing effect is enhanced, the oil drainage early warning channel is additionally arranged, early warning can be conducted in time after sealing leakage, and other losses are prevented from being caused.

Description

Technical Field

[0001] The utility model belongs to the technical field of oil and gas gathering and transportation engineering, and specifically relates to a two-level sealing structure of a flat gate valve. Background Art

[0002] At present, the flat gate valve is widely used in the production process pipeline of oil fields, which is used for cutting off and regulating the fluid pipeline. It can control the flow of fluid through handwheel, electric, pneumatic and other means, so as to realize the control and regulation of the pipeline. After the flat gate valve is installed and used for a period of time, due to the aging and wear of the sealing ring, the conveying medium will leak from the sealing ring. When the leakage is serious, the conveying medium will also leak from the center screw of the handwheel and the top of the electric actuator, causing the actuator to short-circuit and burn out, so that the gate valve cannot be used normally. After the seal of some flat gate valves is lost, the residual pressure cannot be completely released in the pipeline, the seal cannot be replaced, and the leakage problem cannot be solved in time.

[0003] Patent CN218377737U discloses a gate valve stem double sealing device, including a valve body with a flange plate on the top, a valve cover that can be detachably mounted on the top of the flange plate, a rod body that can be rotatably mounted in the valve body, a first-level sealing gasket that can be detachably mounted on the outer edge of the rod body, a stepped boss at the bottom of the boss, an anti-seepage sealing ring that is centrally configured at the bottom of the boss, a sealing groove that is adapted to the first-level sealing gasket and the stepped boss first-level anti-seepage sealing ring for sealing and installation is provided in the valve body, a second-level sealing gasket is configured on the outer edge of the bottom end of the rod body, an anti-seepage clamping ring that is tilted upward is configured on the outer edge of the second-level sealing gasket, a clamping groove that is adapted to the second-level sealing gasket and the anti-seepage clamping ring for sealing and installation is provided in the valve body, and the top of the rod body extends out of the flange plate and the valve cover and is structurally connected with a hand wheel. The gate valve stem double sealing device has a reasonable structure, is conducive to improving the sealing effect between the rod body and the valve body, and has strong practicality.

[0004] Although the above patent discloses a secondary sealing structure, it cannot be replaced when the seal fails, nor can it provide a timely warning after the seal leaks. Utility Model Content

[0005] The purpose of the utility model is to provide a two-level sealing structure of a flat gate valve to overcome the above-mentioned technical problems existing in the prior art.

[0006] To this end, the technical solution provided by the utility model is as follows:

[0007] A two-level sealing structure of a flat gate valve comprises a valve body, a valve plate, a valve stem and a primary sealing device, wherein the valve plate is arranged in the valve body, the valve stem is connected to the top of the valve plate, a sealing seat is connected to the valve body, the primary sealing device is arranged in the sealing seat, a secondary sealing device is also arranged in the sealing seat, the secondary sealing device is arranged above the primary sealing device, and an early warning mechanism is connected to the valve stem after the valve stem passes through the sealing seat.

[0008] The secondary sealing device is in the shape of a circular ring, a sealing filler groove is machined in the middle of the secondary sealing device, a filler pressing cone surface is machined on the inner surface of the lower circular ring, and O-rings are arranged in the sealing filler groove and the filler pressing cone surface.

[0009] A support cylinder is provided above the sealing seat, a screw rod is connected to the top end of the valve stem, the support cylinder is sleeved on the screw rod and the two are threadedly connected, and a hand wheel is connected to the upper part of the screw rod; the early warning mechanism is an oil leakage early warning channel, and the oil leakage early warning channel is connected to the support cylinder.

[0010] The oil leakage warning channel is a copper tube with an inner diameter of 4-5 mm.

[0011] The secondary sealing device is made of soft metal, and the soft metal is brass or copper.

[0012] The beneficial effects of the utility model are:

[0013] The two-level sealing structure of the flat gate valve provided by the utility model prolongs the sealing leakage period of the gate valve by adding a two-level sealing device. At the same time, when the two-level sealing device leaks, the two-level sealing device can be taken out for replacement, thereby solving the technical problem that the gate valve seal cannot be replaced when the flowing medium in the pipeline cannot be completely discharged.

[0014] The secondary sealing structure of the flat gate valve enhances the sealing effect by adding a secondary sealing device, and increases an oil leakage warning channel. When the seal leaks, it will issue a timely warning to prevent other losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure of an implementation method of the utility model;

[0016] Figure 2 It is an overall schematic diagram of the secondary sealing device of the utility model;

[0017] Figure 3 It is a cross-sectional view of the secondary sealing device of the utility model.

[0018] In the figure: 1. valve plate; 2. valve body; 3. valve stem; 4. valve stem threaded part; 5. hand wheel; 6. support cylinder; 7. sealing seat; 8. primary sealing device; 9. secondary sealing device; 10. oil leakage warning channel; 11. sealing packing groove; 12. packing pressing cone surface. DETAILED DESCRIPTION

[0019] The following is an explanation of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0020] The exemplary embodiments of the present invention are now introduced with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0021] Unless otherwise specified, the terms (including technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0022] Example 1

[0023] The utility model provides a two-stage sealing structure of a flat gate valve, such as Figure 1 As shown, it includes a valve body 2, a valve plate 1, a valve stem 3 and a primary sealing device 8, the valve plate 1 is arranged in the valve body 2, the valve stem 3 is connected to the top of the valve plate 1, the valve body 2 is connected to a sealing seat 7, the primary sealing device 8 is arranged in the sealing seat 7, a secondary sealing device 9 is also arranged in the sealing seat 7, the secondary sealing device 9 is arranged above the primary sealing device 8, and the valve stem 3 is connected to an early warning mechanism after passing through the sealing seat 7.

[0024] The utility model is modified to install a secondary sealing device 9 on the upper part of the original flat gate valve and the sealing device, which strengthens the sealing effect and prolongs the sealing leakage cycle of the gate valve. At the same time, an early warning mechanism is added, which will give a timely warning when the seal is lost to prevent other losses.

[0025] Example 2

[0026] Based on Example 1, this embodiment provides a two-stage sealing structure of a flat gate valve, such as Figure 2 As shown, the secondary sealing device 9 is annular, a sealing filler groove 11 is machined in the middle of the secondary sealing device 9, a filler pressing cone surface 12 is machined on the inner surface of the lower ring, and O-rings are arranged in the sealing filler groove 11 and the filler pressing cone surface 12. Figure 3 shown.

[0027] Working principle:

[0028] When the flowing medium passes through the valve plate 1, the medium moves upward along the valve stem 3. When the primary sealing device 8 leaks due to wear and aging, the medium will leak upward along the valve stem 3. Since there is an O-ring in the sealing stuffing groove 11 of the secondary sealing device 9, the medium will be prevented from further leaking upward. When the O-ring in the sealing stuffing groove 11 of the secondary sealing device 9 is also worn and aged, the medium will leak upward through the valve stem threaded part 4 and enter the early warning mechanism, reminding employees that the sealing device has been worn and leaked and needs to be replaced in time.

[0029] Example 3

[0030] Based on Example 1, this embodiment provides a secondary sealing structure of a flat gate valve, wherein a support tube 6 is provided above the sealing seat 7, a screw rod is connected to the top of the valve stem 3, the support tube 6 is sleeved on the screw rod and the two are threadedly connected, and a hand wheel 5 is connected to the upper part of the screw rod.

[0031] When the primary sealing device 8 leaks due to wear and aging, the medium will leak upward along the valve stem 3. Since there is an O-ring in the sealing stuffing groove 11 of the secondary sealing device 9, the medium will be prevented from further leaking upward. When the O-ring in the sealing stuffing groove 11 of the secondary sealing device 9 is also worn and aged, the medium will leak upward through the valve stem threaded part 4 into the support tube 6. At this time, the leaked medium will flow out from the early warning mechanism, reminding employees that the sealing device has been worn and leaked and needs to be replaced in time.

[0032] When the flowing medium in the pipeline cannot be completely discharged, the primary sealing device 8 cannot be replaced. At this time, the low pressure of the remaining flowing medium can be used to take out the secondary sealing device 9 for replacement. When replacing, first loosen the connecting bolts between the sealing seat and the support cylinder, then turn the hand wheel 5, the support cylinder 6 moves up along the screw rod and separates from the sealing seat 7, the second sealing device is exposed, and then the second sealing device is taken out, the O-ring in the sealing stuffing groove 11 is replaced, and then it is installed back on the sealing seat 7, and the same sealing effect can be achieved.

[0033] Example 4

[0034] On the basis of Example 1, this embodiment provides a two-stage sealing structure of a flat gate valve, wherein the warning mechanism is an oil leakage warning channel 10, and the oil leakage warning channel 10 is connected to the support cylinder 6;

[0035] The oil leakage warning channel 10 is a copper tube with an inner diameter of 4-5 mm.

[0036] When an electric actuator is installed on the top of the screw rod, the medium leaking from the valve stem threaded part 4 will flow out from the early warning channel, preventing the leaking medium from continuing to leak upward along the valve stem threaded part 4 into the electric actuator due to the support tube 6 being full, causing a short circuit and burning accident.

[0037] Example 5

[0038] On the basis of Example 1, this embodiment provides a two-level sealing structure of a flat gate valve, wherein the two-level sealing device 9 is made of soft metal, and the soft metal is brass or copper.

[0039] In summary, the two-stage sealing structure of the flat gate valve provided by the utility model uses a two-stage sealing device to extend the sealing leakage cycle of the gate valve; it solves the problem that the original seal of the gate valve cannot be replaced when the residual pressure cannot be completely released, and the newly designed replaceable secondary sealing device 9 solves the leakage problem. The oil leakage warning channel 10 can automatically discharge the leaked medium to prevent the leaked medium from leaking into the electric actuator along the screw rod, causing the actuator to short-circuit and burn out.

[0040] The above examples are merely illustrative of the present invention and do not constitute a limitation on the protection scope of the present invention. All designs that are identical or similar to the present invention fall within the protection scope of the present invention.

Claims

1. A two-stage sealing structure of a flat gate valve, comprising a valve body, a valve plate, a valve stem and a primary sealing device, wherein the valve plate is arranged in the valve body, and the valve stem is connected to the top of the valve plate, characterized in that: The valve body is connected with a sealing seat, the primary sealing device is arranged in the sealing seat, a secondary sealing device is also arranged in the sealing seat, and the secondary sealing device is arranged above the primary sealing device. After the valve stem passes through the sealing seat, an early warning mechanism is connected.

2. A two-stage sealing structure for a flat gate valve according to claim 1, characterized in that: The secondary sealing device is in the shape of a circular ring, a sealing filler groove is machined in the middle of the secondary sealing device, a filler pressing cone surface is machined on the inner surface of the lower circular ring, and O-rings are arranged in the sealing filler groove and the filler pressing cone surface.

3. A flat gate valve secondary sealing structure according to claim 1, characterized in that: A support cylinder is provided above the sealing seat, a screw rod is connected to the top of the valve stem, the support cylinder is sleeved on the screw rod and the two are threadedly connected, and a hand wheel is connected to the upper part of the screw rod; The early warning mechanism is an oil leakage early warning channel, and the oil leakage early warning channel is connected to the support cylinder.

4. A two-stage sealing structure for a flat gate valve according to claim 3, characterized in that: The oil leakage warning channel is a copper tube with an inner diameter of 4-5 mm.

5. A two-stage sealing structure for a flat gate valve according to any one of claims 1 to 4, characterized in that: The secondary sealing device is made of soft metal, and the soft metal is brass or copper.

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