Shut-off device comprising a sealing device

Abstract

A valve includes a housing and a rotary body arranged notably therein with a through opening for a fluid, wherein a flow path is shut off or is at least partially opened in accordance with the rotational angle position of the rotary body about an axis of rotation, wherein the rotary body is connected to a spindle by which the rotary body is rotatable, wherein the housing is provided with a covering, and wherein the spindle reaches through the covering. The spindle is dynamically sealed by a sealing device which follows movements of the spindle relative to the housing and/or to the covering.

Claims

1. A valve, comprising a housing and a rotary body arranged rotatably therein, with a passage opening for a fluid, wherein a flow path is shut off or at least partially opened according to the rotational angular position of the rotary body about a rotation axis; wherein the rotary body is connected to a spindle by means of which the rotary body can be rotated; wherein the housing is provided with a cover; and wherein the spindle extends through the cover; wherein the spindle is dynamically sealed by a sealing device which follows movements of the spindle relative to the housing and to the cover; wherein the sealing device has a first compression ring and a second compression ring; wherein several sealing components are received axially between the compression rings; and wherein the sealing device houses the sealing components inside the sealing device under spring tension of a spring device inside the sealing device; and wherein the first and second compression rings are connected to ensure that the sealing components arranged between the first and second compression rings remain pressed together.

2. The valve as claimed in claim 1, wherein the sealing device has a fixed sealing portion and a dynamic sealing portion, wherein the dynamic sealing portion receives in sealing fashion the circumferential face of the spindle and is movable relative to the fixed sealing portion.

3. The valve as claimed in claim 1, wherein the sealing device has a first anti-extrusion ring and a second anti-extrusion ring which is axially spaced from the first, wherein the two anti-extrusion rings receive the outer circumferential face of the spindle.

4. The valve as claimed in claim 3, wherein several rings or cords with V-shaped, rectangular and/or other shapes of cross-section are arranged between the anti-extrusion rings.

5. The valve as claimed in claim 1, wherein a spring device acts at least on a gland ring, and/or wherein a spring device lies in sprung fashion on a gland ring, wherein the spring device rests directly or indirectly against the cover and/or against the second compression ring.

6. The valve as claimed in claim 1, wherein for static sealing, the sealing device comprises at least one membrane which is arranged between the cover and the housing.

7. The valve as claimed in claim 6, wherein the membrane is connected to the first compression ring.

8. The valve as claimed in claim 6, wherein as well as the first membrane, a further membrane made of a polymer or of polytetrafluoroethylene is provided which lies on the first membrane and is arranged between the cover and the housing.

9. The valve as claimed in claim 6, wherein as well as the first membrane, a body seal is provided which lies on the first membrane and is arranged between the cover and the housing.

10. The valve as claimed in claim 1, wherein the second compression ring has a reinforcing sealing ring or a packing sealable by a gland, wherein the gland is movable by a control element for sealing the valve.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The drawing shows:

(2) FIG. 1 a perspective view of a conical rotary body which is connected to a spindle, wherein the spindle is surrounded by a sealing device,

(3) FIG. 2 a sectional view of the upper part of a valve which has a housing, and a sectional view of the sealing device from FIG. 1, wherein arrows depict a force flow which is independent of the position of the rotary body, housing and cover,

(4) FIG. 3 a sectional view of the upper part of a valve which has a housing and a cover, and a sectional view of the sealing device from FIG. 1,

(5) FIG. 4 the left lower side of the sealing device according to FIGS. 2 and 3, wherein a first anti-extrusion ring is shown, on which several V-shaped rings made of PTFE are arranged so as to form an angular collar,

(6) FIG. 5 a perspective view of the first lower compression ring with a metallic membrane which is impenetrably connected to the compression ring, and

(7) FIG. 6 a depiction of a further sealing device, wherein security means for sealing the valve are shown, wherein a sectional view of the upper part of the valve is shown which has a housing and a cover, and wherein a detail view of the sectional view of the sealing device is shown.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(8) FIG. 1 shows a floating sealing device 1 for a spindle 2, which allows a significant improvement in the tightness against the atmosphere.

(9) The sealing device 1 is guided exclusively by the spindle 2. This achieves as high a tightness as possible, in order to meet the high standards relating to uncontrolled emissions without intervention in the sealing device 1 in a reference period.

(10) A reference period here is a time period during which no access takes place to the sealing device 1. During such a period, the user expects no maintenance to be required.

(11) The spindle 2 is configured integrally with a rotary body 3 in which a passage opening 4 for a fluid is formed.

(12) FIGS. 2 and 3 show a partial sectional view of a valve comprising a housing 5 and a rotary body 3 arranged rotatably therein, with a passage opening 4 for a fluid. A flow path is shut off or at least partly opened according to the rotational angular position of the rotary body 3 about a rotation axis (not shown). The rotary body 3 is connected to a spindle 2 by means of which the rotary body 3 can be rotated. The housing 5 is provided with a cover 6. The spindle 2 extends through the cover 6.

(13) The spindle 2 is integral with and made of the same material as the rotary body 3. It is however also conceivable that the spindle 2 and the rotary body 3 are not formed integrally and/or not of the same material. A structural separation of the spindle 2 and rotary body 3 is conceivable. The rotary body 3 is formed so as to be conical, namely as a conical plug.

(14) The spindle 2 is dynamically sealed by a sealing device 1 which follows movements of the spindle 2 relative to the housing 5 and/or to the cover 6.

(15) FIG. 2 shows that the sealing device 1, 1′ has a fixed sealing portion 1a, 1′a and a dynamic sealing portion 1b, 1′b, wherein the dynamic sealing portion 1b, 1′b receives the circumferential face of the spindle 2 in sealed fashion and is movable relative to the fixed sealing portion 1a, 1′a. The fixed sealing portion 1a, 1′a is formed by membranes described below.

(16) The sealing device 1 has a first anti-extrusion ring 7 which functions less as a guide ring, and a second anti-extrusion ring 8 which is axially spaced from the first and functions more as a guide ring, wherein the two anti-extrusion rings 7, 8 receive the outer circumferential face of the spindle 2 inside the cover 6. The spindle 2 acts on the two anti-extrusion rings 7, 8. The anti-extrusion rings 7, 8 have a guide function. The spindle 2 itself has no operational play.

(17) Several rings 9 of V-shaped cross-section are arranged between the anti-extrusion rings 7, 8. These give extrusion protection for the rings 9 of V-shaped cross-section, which are encapsulated because of the structural arrangement of the spindle 2 and the anti-extrusion rings 7, 8. The rings 9 of V-shaped cross-section are made of polytetrafluoroethylene (PTFE), but may also be made of graphite. The rings 9 of V-shaped cross-section are encapsulated in a ring chamber.

(18) The first anti-extrusion ring 7, as well as the guide function, above all has the function of preventing an extrusion of the rings 9 through a gap. The first anti-extrusion ring 7 may however also not provide any guide function, but merely deploy an anti-extrusion function and be configured only as an anti-extrusion ring.

(19) A spring device 11 acts at least on a gland ring 10. The spring device 11 lies under spring force on the gland ring 10, wherein the spring device 11 rests against a second compression ring 13. An indirect support is also conceivable. The rings 9 of V-shaped cross-section are to this extent connected to a ring guide. The rings 9 of the V-shaped cross-section are held under permanent tension by several spring washers of the spring device 11, wherein the spring washers act on the metallic gland ring 10.

(20) The gland ring 10 may be designed in two pieces. This allows a reduction in effects attributable to expansion phenomena. Such phenomena may be provoked by temperature cycles occurring in any case because of the use of differently tempered media or in specific processes. Many processes have different temperature cycles when the media used in the processes are brought to different temperatures.

(21) Stresses are deflected radially. The force which is exerted on the second compression ring 13 by the spring device 11 is deflected by the structure onto the first compression ring 12. This eliminates all effects on the other components which guarantee an internal tightness.

(22) FIG. 2 shows a mainly diagrammatic view to depict the force flow.

(23) FIGS. 2 and 3 show in detail that the sealing device has a first compression ring 12 and a second compression ring 13, wherein several sealing components are received between the compression rings 12 and 13. FIG. 4 shows detail views of the sealing components.

(24) For static sealing, the sealing device 1 may comprise at least one membrane 14 which is arranged between the cover 6 and the housing 5. Several membranes 14 may be secured metallically between the cover 6 and the housing 5.

(25) FIG. 5 shows that the membrane 14 is connected to the first compression ring 12, namely welded thereto. Other impenetrable connections between the membrane 14 and first compression ring 12 are however also conceivable with respect to FIG. 5.

(26) FIGS. 3 and 6 show that, as well as the first membranes 14, a further membrane 15 is provided which is made of a polymer, lies on a first membrane 14 and is arranged between the cover 6 and the housing 5. The further membrane 15 lies directly on the housing 5.

(27) The further membrane 15 is made of a polymer, in particular PTFE or PTFE compounds, and has a sealing effect which is doubled by a body seal 16 which guarantees the tightness in two directions, namely from inside to outside and vice versa.

(28) The body seal 16 is preferably formed as a flat seal which, in a first radially outer zone, is compressed between the cover 6 and housing 5 and, in a second radially inner zone, is compressed between the membrane 14 and the housing 5.

(29) The sealing effect described above is increased by the use of the second compression ring 13.

(30) FIG. 6 shows that an alternative sealing device 1′ comprises security means for sealing the valve.

(31) For this, the second compression ring 13′ has a reinforcing sealing ring 17 or a packing which may be sealed by a gland 18. The gland 18 is moved by a control element 19. The control element 19 is accessible to a user in an emergency. This device is independent of the cover 6 and may follow adaptation movements of the spindle 2 and rotary body 3, in particular downward movements.

(32) An inner seal, in particular an O-ring 22, guarantees the tightness between the second compression ring 13′ and the first compression ring 12. In the event of failure of the rings 9′, it is necessary to seal a cavity which lies below the reinforcing sealing ring 17 or the packing that can be actuated manually.

(33) Although FIG. 6 shows alternative rings 9′ of rectangular cross-section; however, in a similar fashion to FIG. 2, it is also conceivable to arrange the rings 9 shown in FIG. 3 next to anti-extrusion rings 7, 8.

(34) FIGS. 3 and 6 furthermore show a security pin 21 which ensures that the sealing components arranged between the compression rings 12, 13, 13′ remain pressed together.

(35) FIGS. 3 and 6 furthermore show that at least one adjustment element 20 may be provided for displacing the rotary body 3, in particular axially. In detail, three screw-like adjustment elements 20 are provided in order to create the inner tightness of the valve by downward movements of the spindle 2 and rotary body 3. These adaptation movements or downward movements are preferably oriented axially.

LIST OF REFERENCE SIGNS

(36) 1, 1′ Sealing device

(37) 2 Spindle for rotary body

(38) 3 Rotary body

(39) 4 Passage opening

(40) 5 Housing

(41) 6 Cover

(42) 7 First lower anti-extrusion ring or guide ring

(43) 8 Second upper anti-extrusion ring or guide ring

(44) 9 Ring of V-shaped cross-section of an angular collar

(45) 9′ Rings

(46) 10 Gland ring

(47) 11 Spring device

(48) 12 First lower compression ring

(49) 13, 13′ Second upper compression ring

(50) 14 Metallic membrane

(51) 15 Further membrane made of PTFE

(52) 16 Body seal

(53) 17 Reinforcing sealing ring or packing

(54) 18 Gland

(55) 19 Control element to reinforce seal

(56) 20 Adjustment element

(57) 21 Security pin

(58) 22 Inner seal or O-ring