CN111237484A - An ultra-low temperature low leakage high pressure balance regulating valve - Google Patents

Abstract

The invention relates to an ultralow-temperature low-leakage high-pressure balanced regulating valve which comprises a flange type upper sleeve, a lower sleeve and a valve core, wherein the flange type upper sleeve is connected with the lower sleeve through a flange; the valve core is fixedly connected with one end of the valve rod, and the other end of the valve rod penetrates through the upper valve cover to be connected with the actuating mechanism; an annular groove is formed in the upper end face of the lower sleeve, and a guide wedge-shaped retaining ring and a disc spring group are placed in the annular groove; a PCTFE wedge-shaped sealing element is sleeved on the outer wall of the valve core, a wedge-shaped surface of the outer side surface of the PCTFE wedge-shaped sealing element is abutted against a wedge-shaped surface of the guide wedge-shaped retaining ring, and the inner side surface of the PCTFE wedge-shaped sealing element is attached to and sealed with the outer wall of the valve core; through set up PCTFE wedge sealing member outside the case, keep off the ascending holding power of direction wedge fender with dish spring group and trun into the power that PCTFE wedge sealing member level laminated the case to through the wedge face for the case is laminated sealed with PCTFE wedge sealing member all the time at the lift in-process, has solved the big problem of leakage of balanced sealing washer under the ultra-low temperature environment.

Description

An ultra-low temperature low leakage high pressure balance regulating valve

technical field

The invention relates to a valve body, in particular to an ultra-low temperature, low leakage and high pressure balance type regulating valve.

Background technique

With the continuous expansion of my country's LNG and air separation plant market, the demand for low-temperature valves is increasing, and the pressure level requirements for low-temperature valves are also higher. The traditional low-temperature and high-pressure regulating valves have large internal leakage and external leakage. The problems are becoming more and more obvious and need to be solved urgently. Most of the low-temperature and high-pressure valves used in my country are imported. In the field of low-temperature industrial automation control in China, limited by the sealing and reliability of the traditional single low-temperature balance sealing ring, it is difficult for users to meet the requirements of ultra-low temperature, low leakage and high pressure. Poor requirements, this ubiquitous phenomenon greatly restricts the research and development of domestic ultra-low temperature and high pressure valves.

To sum up, in order to meet the requirements of high pressure difference, low leakage and ultra-low temperature, solving the problem of large leakage of domestic balanced sealing rings in ultra-low temperature environment has become an urgent problem for our company's researchers.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is: the leakage of the balance sealing ring in the ultra-low temperature environment is large;

In order to solve the above-mentioned technical problems, the present invention adopts the following technical solutions:

The invention relates to an ultra-low temperature, low leakage and high pressure balanced regulating valve, which comprises an upper sleeve and a lower sleeve which are clamped to each other; the upper sleeve and the lower sleeve are provided with a through hole for lifting and lowering the valve core; the valve core and the valve stem One end of the valve stem is fixedly connected, and the other end of the valve stem is connected to the actuator through the upper valve cover; the upper end face of the lower sleeve is provided with an annular groove, and a guiding wedge-shaped retaining ring is placed in the annular groove. The disk spring used to support the guiding wedge-shaped retaining ring Group; a PCTFE wedge-shaped seal is sleeved on the outer wall of the valve core, the wedge-shaped surface of the outer side of the PCTFE wedge-shaped seal is abutted against the wedge-shaped surface of the guide wedge-shaped retaining ring, and the inner surface of the PCTFE wedge-shaped seal is sealed with the outer wall of the valve core;

The traditional single low temperature and high pressure balance sealing ring is deformed at ultra-low temperature, resulting in the leakage of the medium from the balance sealing ring. The invention adopts the wedge-shaped seal made of PCTFE, and the PCTFE wedge-shaped seal is not easily deformed at low temperature; an annular groove is provided on the lower sleeve, and a disc spring group is arranged in the annular groove, and the disc spring group is used to support the guide wedge-shaped retaining ring , the wedge-shaped surface on one side of the guiding wedge-shaped retaining ring is matched with the wedge-shaped surface on one side of the PCTFE wedge-shaped seal, and the upward support force of the disc spring group on the guiding wedge-shaped retaining ring is transferred to the PCTFE wedge-shaped seal through the wedge-shaped surface to fit the valve core horizontally. The force makes the valve core always fit and seal with the PCTFE wedge seal during the lifting process.

In order to ensure that the supporting force of the disc spring group acting on the guide wedge-shaped retaining ring remains consistent, the present invention adopts a limiting ring extending downwardly from the guiding wedge-shaped retaining ring, the limiting ring is placed in the annular groove, and the limiting ring is sleeved with Disc spring group;

The limit ring makes the guide wedge-shaped retaining ring and the valve core set concentrically, and the limit ring can only move up and down due to the limitation of the disc spring group, so as to ensure that the PCTFE wedge-shaped seal acts on the PCTFE wedge-shaped seal equally everywhere, thus ensuring the same movement of the valve core. Axiality.

In order to prevent rainwater and condensed water from entering the thermal insulation layer, the present invention adopts at least one drip plate welded horizontally on the outer wall of the upper valve cover;

The drip plate can not only prevent rainwater and condensed water from entering the insulation layer, but also relieve the upward transfer of valve body temperature. After theoretical research and experimental verification, the present invention welds two drip plates on the upper bonnet, which can effectively reduce the length of the upper bonnet. It has two advantages: first, it reduces the length of the upper bonnet and reduces the consumption of materials. , and always keep the temperature at the packing above 0 °C; second, reduce the length of the upper bonnet, the length of the valve stem is also shortened, and the deformation and deflection of the valve stem are correspondingly reduced to ensure that the coaxiality between the valve core and the valve stem is excellent. To achieve the goal of low leakage of the valve.

In order to ensure the sealing between the valve stem and the upper valve cover, the present invention adopts a packing bottom gasket located at the gap between the valve stem and the upper valve cover, and an O-ring is arranged on the outside of the packing bottom gasket to fit with the inner wall of the upper valve cover; the inner side of the packing bottom gasket A valve stem sealing ring is arranged to fit with the outer wall of the valve stem; the bottom of the packing bottom pad is provided with a packing flat pad to prevent the valve stem sealing ring from being deformed and stuck in the gap between the valve stem and the upper valve cover.

The traditional sealing at the stuffing box only prevents the leakage of the medium by compressing the packing, which not only requires high quality of the packing, but also greatly increases the friction of the valve stem after the excessively compressed packing. In order to solve this problem, the valve stem balance sealing ring is added to the inner hole of the packing bottom gasket, and an O-ring is added to the outer edge of the packing bottom gasket, which effectively reduces the friction of the valve stem and realizes the characteristics of internal and external micro-leakage at the packing box, making the The reliability and safety of the valve are greatly improved; in summary, O-rings and stem sealing rings are set on the inner and outer sides of the packing bottom gasket, so that the medium flowing into the gap between the valve stem and the upper bonnet can be double-sealed inside and outside; in order to To prevent the valve stem sealing ring from being deformed and stuck in the gap between the valve stem and the upper valve cover, the present invention adds a packing flat pad on the packing bottom pad, and the packing pad will not deform during the movement of the valve stem, thereby preventing the valve stem from being deformed. The sealing ring is snapped into the gap between the valve stem and the upper bonnet; in addition,

In order to illustrate the connection relationship between the valve body, the upper valve cover, the upper sleeve and the lower sleeve, the present invention adopts the upper valve cover to be fixedly connected to the valve body, the top of the upper sleeve is provided with annular support ears, and the upper and lower end surfaces of the support ears are provided with seals The gasket is clamped at the connection between the upper valve cover and the valve body; the bottom of the lower sleeve is provided with a gap, and the middle of the valve body is provided with a boss for supporting the gap;

In the present invention, bolts and nuts are used to connect the upper valve cover and the valve body. In addition, the top of the upper sleeve is provided with a support lug, and the support ear is provided with a sealing gasket and is clamped at the connection between the upper valve cover and the valve body to prevent the medium from flowing from the upper valve body. Leakage at the connection between the cover and the valve body;

In summary, the boss of the valve body is used to support the lower sleeve, the upper and lower sleeves are clamped to each other, and the upper sleeve is connected to the valve body through the support lugs and the upper valve cover, so as to realize the valve body, the upper valve cover, the upper sleeve, Connection of the lower sleeve.

Beneficial effects of the present invention: The present invention is an ultra-low temperature, low leakage, high pressure balanced regulating valve. By arranging a PCTFE wedge-shaped seal outside the valve core and a guide wedge-shaped baffle ring against the PCTFE wedge-shaped seal, the disc spring group is guided to the The upward supporting force of the wedge-shaped block is converted into the force of the PCTFE wedge-shaped seal to fit the valve core horizontally through the wedge-shaped surface, so that the valve core and the PCTFE wedge-shaped seal always fit and seal during the lifting process, which solves the problem of the balance seal ring in the ultra-low temperature environment. The problem of large leakage.

Description of drawings

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Fig. 1 is the structural representation of the present invention;

Fig. 2 is the enlarged view of Fig. 1 II;

Fig. 3 is an enlarged view of Fig. 1I;

Fig. 4 is the enlarged view of Fig. 1III place;

In the figure: 1-upper sleeve, 2-lower sleeve, 3-valve core, 4-valve stem, 5-upper bonnet, 6-annular groove, 7-guide wedge-shaped retaining ring, 8-disc spring group, 9 -PCTFE wedge seal, 10-limit ring, 11-drip plate, 12-packing bottom gasket, 13-O-ring, 14-stem seal, 15-packing flat gasket, 16-valve body, 17-ring Lugs, 18-notch.

Detailed ways

The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are all simplified schematic diagrams, and only illustrate the basic structure of the present invention in a schematic manner, so they only show the structures related to the present invention.

As shown in Figures 1-2, the present invention is an ultra-low temperature, low leakage, high pressure balanced regulating valve, comprising an upper sleeve 1 and a lower sleeve 2 that are clamped to each other; The valve core 3 is a through hole for lifting; the valve core 3 is fixedly connected with one end of the valve stem 4, and the other end of the valve stem 4 is connected to the actuator through the upper valve cover 5; the upper end surface of the lower sleeve 2 is provided with an annular groove 6, which is annular A guide wedge-shaped retaining ring 7 and a disc spring group 8 for supporting the guiding wedge-shaped retaining ring 7 are placed in the groove 6; a PCTFE wedge-shaped seal 9 is sleeved on the outer wall of the valve core 3, and the wedge-shaped surface on the outer side of the PCTFE wedge-shaped seal The wedge-shaped surface of the guide wedge-shaped retaining ring 7 is abutted, and the inner surface of the PCTFE wedge-shaped sealing member 9 is fitted and sealed with the outer wall of the valve core 3;

The traditional single low temperature and high pressure balance sealing ring is deformed at ultra-low temperature, resulting in the leakage of the medium from the balance sealing ring. The invention adopts the wedge-shaped seal made of PCTFE, and the PCTFE wedge-shaped seal is not easily deformed at low temperature; an annular groove is provided on the lower sleeve, and a disc spring group is arranged in the annular groove, and the disc spring group is used to support the guide wedge-shaped retaining ring , the wedge-shaped surface on one side of the guiding wedge-shaped retaining ring is matched with the wedge-shaped surface on one side of the PCTFE wedge-shaped seal, and the upward support force of the disc spring group on the guiding wedge-shaped retaining ring is transferred to the PCTFE wedge-shaped seal through the wedge-shaped surface to fit the valve core horizontally. The force makes the valve core always fit and seal with the PCTFE wedge seal during the lifting process.

As shown in FIG. 2 , in order to ensure that the supporting force of the disc spring group acting on the guide wedge-shaped retaining ring remains consistent, the present invention adopts a limiting ring 10 extending downward from the guiding wedge-shaped retaining ring 8 , and the limiting ring 10 is placed in the annular groove 6 inside, and the limit ring 10 is sleeved with a disc spring group 7;

The limit ring makes the guide wedge-shaped retaining ring and the valve core set concentrically, and the limit ring can only move up and down due to the limitation of the disc spring group, so as to ensure that the PCTFE wedge-shaped seal acts on the PCTFE wedge-shaped seal equally everywhere, thus ensuring the same movement of the valve core. Axiality.

As shown in FIG. 1, in order to prevent rainwater and condensed water from entering the insulation layer, the present invention adopts at least one drip plate 11 welded horizontally on the outer wall of the upper valve cover 5;

The drip plate can not only prevent rainwater and condensed water from entering the insulation layer, but also relieve the upward transfer of valve body temperature. After theoretical research and experimental verification, the present invention welds two drip plates on the upper bonnet, which can effectively reduce the length of the upper bonnet. It has two advantages: first, it reduces the length of the upper bonnet and reduces the consumption of materials. , and always keep the temperature at the packing above 0 °C; second, reduce the length of the upper bonnet, the length of the valve stem is also shortened, and the deformation and deflection of the valve stem are correspondingly reduced to ensure that the coaxiality between the valve core and the valve stem is excellent. To achieve the goal of low leakage of the valve.

As shown in FIG. 3 , in order to ensure the sealing between the valve stem and the upper valve cover, the present invention adopts a packing bottom gasket 12 located at the gap between the valve stem 4 and the upper valve cover 5 , and an O-ring 13 and an O-ring 13 are arranged on the outside of the packing bottom gasket 12 . The inner wall of the upper valve cover 5 is fitted; the inner side of the packing bottom gasket 12 is provided with a valve stem sealing ring 14 which is fitted with the outer wall of the valve stem 4; the bottom of the packing bottom gasket 12 is provided with a valve stem sealing ring 14 to prevent the deformation of the valve stem 4 and the upper valve. Filling flat pad 15 at the gap of cover 5.

The traditional sealing at the stuffing box only prevents the leakage of the medium by compressing the packing, which not only requires high quality of the packing, but also greatly increases the friction of the valve stem after excessively compressing the packing. In order to solve this problem, the valve stem balance sealing ring is added to the inner hole of the packing bottom gasket, and an O-ring is added to the outer edge of the packing bottom gasket, which effectively reduces the friction of the valve stem and realizes the characteristics of internal and external micro-leakage at the packing box, making the The reliability and safety of the valve are greatly improved; in summary, O-rings and stem sealing rings are set on the inner and outer sides of the packing bottom gasket, so that the medium flowing into the gap between the valve stem and the upper bonnet can be double-sealed inside and outside; in order to To prevent the valve stem sealing ring from being deformed and stuck in the gap between the valve stem and the upper valve cover, the present invention adds a packing flat pad on the packing bottom pad, and the packing pad will not deform during the movement of the valve stem, thereby preventing the valve stem from being deformed. The sealing ring is snapped into the gap between the valve stem and the upper bonnet; in addition,

As shown in FIG. 4, in order to illustrate the connection relationship between the valve body, the upper valve cover, the upper sleeve and the lower sleeve, the present invention adopts the upper valve cover 5 to be fixedly connected with the valve body 16, and the top of the upper sleeve 1 is provided with an annular support lug 17. Sealing gaskets 18 are provided on the upper and lower end surfaces of the lugs 17, and are clamped at the connection between the upper valve cover 5 and the valve body 16; the boss;

In the present invention, bolts and nuts are used to connect the upper valve cover and the valve body. In addition, the top of the upper sleeve is provided with a support lug, and the support ear is provided with a sealing gasket and is clamped at the connection between the upper valve cover and the valve body to prevent the medium from flowing from the upper valve body. Leakage at the connection between the cover and the valve body;

In summary, the boss of the valve body is used to support the lower sleeve, the upper and lower sleeves are clamped to each other, and the upper sleeve is connected to the valve body through the support lugs and the upper valve cover, so as to realize the valve body, the upper valve cover, the upper sleeve, Connection of the lower sleeve.

The invention is an ultra-low temperature, low leakage and high pressure balance type regulating valve. By arranging a PCTFE wedge-shaped seal outside the valve core and a guide wedge-shaped retaining ring against the PCTFE wedge-shaped seal, the disc spring group can block the upward supporting force of the guide wedge. By turning the wedge-shaped surface into the force of the PCTFE wedge-shaped seal to fit the valve core horizontally, the valve core and the PCTFE wedge-shaped seal always fit and seal during the lifting process, which solves the problem of large leakage of the balance sealing ring in the ultra-low temperature environment.

Taking the above ideal embodiments according to the present invention as inspiration, and through the above description, relevant personnel can make various changes and modifications without departing from the technical idea of the present invention. The technical scope of the present invention is not limited to the contents in the specification, and the technical scope must be determined according to the scope of the claims.

Claims (5)

1. The utility model provides an ultra-low temperature low leakage high pressure balanced type governing valve which characterized in that: comprises a flange type upper sleeve, a lower sleeve and a valve core;

the valve core is fixedly connected with one end of the valve rod, and the other end of the valve rod penetrates through the upper valve cover to be connected with the actuating mechanism;

an annular groove is formed in the upper end face of the lower sleeve, and a guide wedge-shaped retaining ring and a disc spring group used for supporting the guide wedge-shaped retaining ring are placed in the annular groove;

the outer wall of the valve core is sleeved with a PCTFE wedge-shaped sealing element, a wedge-shaped surface of the outer side surface of the PCTFE wedge-shaped sealing element is abutted to a wedge-shaped surface of the guide wedge-shaped retaining ring, and the inner side surface of the PCTFE wedge-shaped sealing element is attached to the outer wall of the valve core in a sealing mode.

2. The ultra-low temperature low leakage high pressure balanced type regulator valve of claim 1, wherein: the limiting ring is arranged in the annular groove, and the disc spring group is sleeved on the limiting ring.

3. The ultra-low temperature low leakage high pressure balanced type regulator valve of claim 1, wherein: at least one water dripping plate is horizontally welded on the outer wall of the upper valve cover.

4. The ultra-low temperature low leakage high pressure balanced type regulator valve of claim 1, wherein: a filler bottom pad is arranged at the gap between the valve rod and the upper valve cover, and an O-shaped ring is arranged on the outer side of the filler bottom pad and attached to the inner wall of the upper valve cover; a valve rod sealing ring is arranged on the inner side of the packing bottom pad and is attached to the outer wall of the valve rod;

the bottom of the packing bottom pad is provided with a packing flat pad which prevents the valve rod sealing ring from being deformed and clamped into a gap between the valve rod and the upper valve cover.

5. The ultra-low temperature low leakage high pressure balanced type regulator valve of claim 1, wherein: the upper valve cover is fixedly connected with the valve body, the top of the upper sleeve is provided with an annular support lug, the upper end surface and the lower end surface of the support lug are both provided with sealing gaskets, and the upper end surface and the lower end surface of the support lug are clamped at the joint of the upper valve cover and the valve body;

the bottom of the lower sleeve is provided with a notch, and the middle part in the valve body is provided with a boss for supporting the notch.

Images