AU618078B2 - Process and device for protection and support of a seal in a valve arrangement - Google Patents

Description

PcI OPI DATE 11/08/89 APPLN. I D 30675 89 INTERNATIONAL AOJP DATE0/98 INTERNATIONALTE0/98 PCT NUMBER PCT/EP89/OOLIL (51) Internationale Patentklassifikation 4: F161( 3/244 25/00 (11) Internationale Veroffentlichungsnummer: WO 89/ 06763 Al (43) Internationales Verofentlichungsdatumn; 27. JI 1989 (27.07-89) (21) Internatlonales Akienzeichen: PCT/EP89/00044 (22) Internationales Anineldedaturn: 17. Januar 1989 (17.01.89) (31) Priorititsaktenzeichen: (32) Prioritatsdaten: (33) Priorititsland: P 38 01 569.2 P 38 01 561,7 20. Januar 1988 (20.01.88) Januar 1988 (20.01,88)

DE

(8 fsil~nug atz. AT ijro cbes Patent), AU, 4BE (euro -ch ten ,BR (europliscbes Patent), DE (europ isches Paten" DK, Fl, FR (europaisches Patent), GB (europlisches Patent), IT (europliisches Patent), JP, KR, LU (europtiisches Patent), NL (europtiisches Patent), NO, SE (europtlisches Patent), SU, US.

Veriiffentlicht Mit internationalern Recherchenbericht, Vor A blauf derfir Anderungen der A nspriiche zugelassenen Frist, Ver6ffentlichung wird wiederholt falls Anderungen eintreffen.

(7lX72) Anmelder und Erfinder: MIETH, Hans, Otto [DE/ DE]; Sandkrug, 3, D,2058 Schnakenbek (DE), (72) Erfinder; und Erfinder/Anmelder (nurfir US) SCHLOTTERBECK, Erich [DE/DE]; Pflasterstralie 4A, D-2053 Schwarzenbek (DE).

(54)Title: PROCESS AND DEVICE FOR PROTECTION AND SUPPORT OF A SEAL IN A VALVE ARRANGE-

MENT

(54)Bezeichnung; VERFAHREN UND VORRICHTUNG ZIJM SCHUTZ, UND ZUR STf..TZUNG, EINER DICH- TUNG EINER VENTILVORRICI-TUNG (57) Abstract A process and a device are useful for protecting and suppnrting a seal in, a 1 5 71 5a 9 4 Valve arrangement, The device comprises a closure member designed as a slide gate having a translational or rotationat movement, a seat region of the valve housing parts corresponding to said closure member, a closure part which can slide in the direction of the degree of freedom of the closure member, and a seal or sealing position which is effective between the closure member and the seat region or which co-operates with the closure part. Said process and device ensure, amongst others, that the seal in a valve arrangement of the type described in the Introductory part Is protected and supported in positions other than the closed position, To this end, the load on the seal or sealing position which ensures sealing in the closed position of the Valve arrangement is applied by the closure part in positions other than theL closed position. 2 6 (57) Zusamnmenfassung Die Erfindurig betrifft ein Verfahren und elne Vorrichtung zum Schutz und zur Sttltzung elner Dichtung elner Ven.

tilvorrlchtung, mit elnem schieberartig ausgebildeten, translatorisch oder rotativ verschiebbaren Schlleliglied,, einem hlerzu korrespondierenden Sltzbereich der Ventilgehllauseteile und elnem Verschluliteil, weiches in Rkhltung des Bewegungsfrel.

heitsgrades des Schlieligliedes verschlebbar ist,, und einer Dichtung bzw, Abdlchtungsstelle, die entweder zwischen Schlicet.

glied und Sitzbereich wirksamn ist oder mit dem Verschluliteill zusammen wirkt. Durch das vorgesohlagene Verfahren und die Vorrlchtung, zu seiner Realisierung wird tinter anderem sichergestelit. dali bel elner Ventlivorrichtung der einieltend gekennzeichneten. Gattung die Dichtung in anderen Stellungen als in der Schljelistellung geschtltzt und gest~tzt ht. Dies wird unter anderemn verfahrenstechnisch dadurch erreicht, daB die in der Schlielistellung der Ventilvorrlchtung. eine Dichtwir.

kung erzeugende Beanspruchung der Dichtung bzw,. Abdlchttungsstelle In anderen Stellungeri als in der Schileistellung durch das Verschlulitell hervqrgertifen wird, I a I 0 a.* *0 0 200 *:a *0 S

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*5 0?( 0 Sl rI 2 APPARATUS FOR PROTECTING AND SUPPORTING A SEAL OF A VALVE The invention relates to an apparatus for protecting and for supporting a seal of a valve comprising a valve comprising a casing defining an inner cavity and a seat region, a closing member which is displaceable translatorily or rotatively in the casing, a locking element which is displaceable in the direction of motion of the closing member, and sealing means which is either active between said closing member and said seat region or cooperates with said locking element, said sealing means comprising two seals or two sealing places, said closing member having a leakage cavity between the seals or sealing places and at least one conduit connected to said leakage cavity, said seal or sealing places being engaged by said locking element when the valve is other than closed such that the strain on the seal or sealing place producing a sealing effect in the closed position of the valve is replaced by engagement between said seals or sealing places and the locking element in positions other than the closed position.

A valve of the initially identified group of the art is known from DE-A-37 01 027 and also from Euopean Patent Application 0 279 177. The subject matters of the above mentioned patent applications according to the respective permeables of the main claims start out from a valve with a leakage cavity which is provided with two sealing places arranged in series and preventing in the closed position of the valve the overflow of fluids from one valve casing tbspe.011/mieth.spe 91 2 19 -3part into another. In the last mentioned patent application the two sealing places inter alia are realized by means of a sealing arrangement comprising two separate seals arranged on the side of the valve casing, said two discrete seals inter alia being provided as seals with circular cross section. As far as the two known valves are concerned the leakage cavity is arranged between the sealing places and connected with the environment of the valve via the valve casing. Said co-called double-seat valves, apart from the control of the medium inlet from the inner cavity of the valve to the leakage cavity known per se in connection with the closed position of the valve, solve the technical problem to control this inlet also in other positions of the valve. The solution of this technical prrblem is achieved in that the medium inlet from the inner cavity to the leakage cavity is controlled in positions other than the closed position of the valve by means of a provision substituting the closing m member to have the same effect as in the closed position with respect to its interaction with the leakage cavity.

With view to the actual realization of the object there is provided, among others, a locking element comprising an inner passage which is disposed in relatively mobile relationship to the closing member in the direction of the degree of its freedom of motion. Thereby the locking element, at least in the open position of the valve, is in permanent contact with the two sealing places or the two seals.

In each and every case of use the known locking tbspe.O011/mieth.spe 91 2 19 -4element is always in interaction with two seals or sealing places and according to its purpose it alone controls the medium inlet from the inner cavity to the leakage cavity between the two seals or sealing places.

As far as the known valves are concerned the locking element takes over, in positions other than the closed position of the valve, the protection and the support of the two seals or sealing places, if these are realized by sealing means arranged on the side of the valve casing. For seals arranged on the side of the closing member the known locking element in the proposed arrangement and mode of operation does not provide any protection or support.

Starting out from the state of the art shown it is the problem of the present Sinvention to ensure with a valve of the initially identified group of the art protection and support of the seal in positions other than the closed position. It is now intended to mainly show solutions which protect and support in particular seals arranged on the side of the closing member.

The invention provides a valve comprising a valve comprising a casing defining an inner cavity and a seat region, a closing member which is displaceable translatorily or rotatively in the casing, a locking element which is displaceable in the direction of motion of the closing member, sealing means comprising two seals or two sealing places which in the closed position of the valve engages said closing member S 20 and said seat region to produce a sealing effect, a leakage cavity between the seals or sealing places and at least one conduit through the closing member and connected to said leakage cavity, said seals or sealing places being engaged by said locking element, when the valve is other than closed, such that the strain on the seals or sealing places producing a sealing effect in the closed position of the valve is replaced by engagement of said seals or sealing places with the locking element.

The present invention shows how the interaction principle, known from the above mentioned patent application, between the locking element on the one hand and thile valve casing, the two seals or scaling places and the leakage cavity on the other hand, is now analogously replaced by an interaction principle between the locking element on the one hand and the closing member, the seal(s) or the sealing places and a leakage cavity on the other hand. Thereby it is achieved on the one hand that the i.i i i -i II i -1 I i locking element protects and supports a seal or even two seals disposed on the side of the closing member in positions other than the closed position of the valve. If between the two seals disposed on the side of the closing member there is provided a leakage cavity, the medium inlet from the inner cavity to the leakage cavity will also be controlled in positions other than the closed position of the valve with the same effect as in the closed position by means of an arrangement substituting the closing member with respect to its interaction with the leakage cavity.

The newly created valve is also capable of solving all of the known problems as explained in detail in the

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1 e e *me* e e eo Pif 6 above mentioned patent applications. There the most different procedures and features are indicated as solutions. They can be applied analogously and in an obvious manner to the newly created valve.

Two seals disposed on the side of the closing member, between which there is provided a leakage cavity which is connected via conduits with the environment of the valve, can be cleaned with the agents known from the above identified patent applications, in both the closed position and the open position of the valve. The cleaning of a single seal which is either disposed on the side of the valve casing or on the side of the closing member and which according to the invention is protected in all valve positions against the inner cavity of the valve casing, is provided according to an advantageous embodiment of the valve according to the invention in that the locking element is made to be permeable in the region where it overlaps the seal of the inner cavity of the valve casing in the direction of the seal. Since in this case the locking element needs not assume a sealing function but is merely to protect and support the seal when positioned on the side of the casing in the open position of the valve, it may, for example, be provided with a plurality of openings.

One further advantage achieved with the invention resides in the fact that the action principle known from DE-A-37 01 027 and EP-0 279 177 between locking element and seals arranged on the side of the valve casing is consistently transferred and applied to valves of the most

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0S SvY C~ 00 simple structure with a single on/off-function on the one hand and to complex valves means with the most different switching functions and properties on the other hand.

Thus it was possible for the first time to dispose a seal with circular cross section, a so-called O-ring, with restricted mobility in a groove on the side of the valve casing, which seal though simple in structure constituted a not unproblematical sealing element particularly if disposed on the side of the valve casing, since also in the open position of the valve said seal was fixed by the locking element in a position equivalent to that in the closed position of the valve. This has the further effect that also in the open position of the valve it is not exposed to the mechanical strain caused by the flow agent. In the known sealing arrangements the seal disposed on the side of the casing is completely open to the inner cavity of the valve casing when the valve is in the open position. The seal is subjected, without any protection, to flow forces, corrosion and erosion of the flowing agent, at least on its surface facing the inner cavity of the valve casing.

Without specific measures the problem of loose sealing arrangements cannot be solved with the means known so far. However, e.g. in the USA such loose secling arrangements are coercive measures provided as standard solutions for biological and cleansing reasons, yet hitherto the problem was solved in a generally unsatisfactory manner there because the above described mechanical instability of the seal was accepted or the tbspe.010/mieth.spe 91 2 19 i "1 lj_ -_li .i i .ili:- II -i~iii-- llii-~~: i) 8 seal was reinforced or disposed in a cage. The present invention solves the problem existing in connection with the loosely arranged annular seal with relatively simple means.

Since the principle of interaction between locking element and closing member as proposed according to the invention results in an enveloping of the locking element by the closing member in the open position of the valve, the feature for the locking element to be gathered from the known valves, i.e. the mandatory so-called "inner passage" is not applicable. In the open position of the valve the flowing agent now no longer flows through the locking element. This results in the advantage residing .in the fact that the seat region with view to its passage i cross section is no longer narrowed by the annular cross section of the locking element. A further advantage is to be seen in the fact that the locking element is conducted on or at the closing member with which, in the v open position of the valve, it forms an embrace. It is true that the known valve the locking element is also run *go on or at the closing member, yet the formation of an embrace is completed with the seat region of the valve S casing. In so far the means according to the invention 0* result in less strict requirements concerning guiding quality and/or an aligning arrangement between closing member axis and valve casing.

With reference to the figures of the drawing briefly discussed in the following the substantial features of the subject matter of the application are shown as examples tbspe. OlO/mieth.spe 91 2 19 i~ -9 and described with respect to their mode of action. The following reference numerals and designations are used (see list): List of Designations 09 00 fee 0*~ 00 Og

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00Cc *s S 0 1,2 la 3 4 4a 4b 4c 5 5a 6 6a 7 71 72 8 9 11 12 13 14

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valve casing casing groove seat region closing member first bar outlet tube groove locking element second bar leakage cavity drain bore seal first seal second seal distribution and jet means parittion wall feeding region outlet region cleaning tube annular gap casing seal diameter of the seat region leakage outlet/leakage

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0 C 00e@ S0 0, 23 fvr A tbspe. 010/mieth.spe 91 2 19

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10 R (feeding and/or outlet of cleansing agent) (cleanuing agent) V passage flow Figure 1 shows a center section through an embodiment of the valve according to the invention comprising two seals disposed on the side of the closing member and a leakage cavity provided in between, also in the closed position and in the open position; Figure 2 and Figure 3 show a center section through an embodiment according to Figure 1 with a cleansing agent inlet to the leakage cavity in the closed position and the open position of the valve; Figure 4 shows an embodiment according to Figures 2 and 3 with modified cleansing agent inlet and outlet, respectively; Figures 5 to 8 each show a center section through a S. valve according to Figures 5 and 6 with seals having restricted mobility and a differently constructed inlet for the cleansing agent and a differently constructed 0 outlet for the cleansing agent or the leakage; Figure 9 shows a center section both in the closed

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position and in the open position, of a modification which may be applied to the preceding embodiments, with the sealing means disposed on the side of the valve casing.

From Figure I there is evident the above mentioned substitution principle of a locking element 5 and a seat region 3 of a valve casing 1, 2 with view to a closing tbspe.l00/mieth. spe 91 2 19 r 11 member 4 and its seals 71 and 72. In the left-hand side representation the closed position of the valve is shown, wherein a representation of the means for actuating closing member 4 and locking element 5 was dispensed with.

Seat region 3 is in interaction with closing member 4 and its seals 71 and 72. In the open position of the valve (right-hand side representation) the action of seat region 3 with respect to seals 71 and 72 is substituted by locking element 5. The strain on seals 71 and 72 produced in the closed position of the valve and causing a sealing effect is produced by locking element 5 in positions other than the closed position. In the open position of the valve a passage flow V flows from valve S* casing part 1 to valve casing part 2 or vice versa. With view to the bore receiving closing member 4 locking element 5 exhibits the same dimension D as the connection 0 bore of valve casing parts 1, 2 in their seat region 3.

e The schematically shown valve is an inhibit valve with *O on/off-function.

The two seals 71, 72 have between them a leakage cavity 6. In the closed position of the valve said leakage cavity 6 on the one hand is defined by valve casing part 1, 2, and on the other hand is connected with the environment of closing element 4 via a drain bore 6a provided within said closing member 4. There is known a number of solutions for arranging drain bore 6a within said closing member 4, e.g. drain bore 6a can be arranged in an outlet tube 4b, which is connected with closing member 4 and projects from valve casing part 2. The Stbspe.OlO/mieth.spe 91 2 19 1111111" -111111 111 11 1 I O F 1 I, 12 S *0 00** 2

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0 L S"O- reversal thereof is also feasible, in that outlet tube 4b is arranged on the side of valve casing part 1 and extends therefrom to the environment of the valve. In the last mentioned case, drain bore 6a is then located in a first bar 4a by means of which closing member 4 is activated.

Further embodiments of the valve with view to the arrangement of drain bore 6a are shown also in Figures 6, 7 and 8 (drain bore 6a is an outlet tube 4b emerging in downward direction). The right-hand side representation of Figure 1 shows the leakproof valve in its open position. Now the outside of leakage cavity 6 is defined by the inner jacket surface of locking element 5. In both the closed and the open position of the valve the leakage cavity 6 is closed against the inner cavity of valve casing parts I or 2. It can furthermore be recognized that with view to seals 71 and 72 and with view to leakage cavity 6 the locking element 5 substitutes seat region 3 of the valve casing pasts 1 and 2. In seat region 3 there can be arranged, not shown in Figure 1, a seat ring which is equally provided with the above mentioned functions on the side of the casing.

In figures 2, 3 and 4 a closing member 4 is shown which, in concurrence with the respective embodiment of the valve according to Figure 1, is equipped with two seals 71 and 72, said seals defining between them leakage cavity 6. Said leakage cavity 6 is not only connected to the environment of the valve via a drain bore 6a, as shown in Figure 1, but furthermore comprises a second connection path to the environment of the valve through which tbspe.010/mieth.spe 91 2 19

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13 cleansing liquid can be introduced to leakage cavity 6.

The above mentioned kind of leakage and/or cleansing agent-discharge (in Figures 2 and 3 designated L/R) and the cleansing agent feed R can also be applied to a sealing arrangement according to the embodiment of figure 4 wherein the two seals 71 and 72 are arranged with restricted mobility in closing member 4. Solutions in this respect can be gathered from DE-A-37 01 027 and EP-0 279 177. Figures 5, 6, 7, and 8 furthermore show solutions how cleansing agent can be fed into leakage cavity 6 or is conducted thereto.

Closing member 4 can e.g. be a hollow body between seals 71 and 72 (Figure the cleansing liquid being fed via distribution and jet-spraying means 8 to the area of If) seals 71 and 72.

The area between seals 71 and 72 can also be divided by a partition wall 9 (Fig.6), which forms a feed region 10 and an outlet region 11, so that the cleansing agent R is necessarily fed to the seal area and also discharged therefrom again.

In the embodiment according to Figure 7 a cleaning tube 12 with the distribution and jet-spraying means 8 is disposed in drain bore 6a of outlet tube 4b. Cleansing liquid R is fed to the sealing region and drained from there via an annular gap 13, formed between the inner wall of outlet tube 4b and cleaning tube 12.

0 The structure of the embodiment according to Figure 8 substantially corresponds to that of Figure 6, the feed for cleansing liquid R and the drain for the leakage tbspe.010/mieth.spe 91 2 19 14and/or the cleansing fluid L/R being provided at one side of closing member 4. The drive of closing member 4 is either effected by bar 4a, which is provided on that side of closing member 4 which is opposite to outlet tube 4b, and extends from valve casing part 1 or, if the first bar 4 a is omitted, via outlet tube 4b, the position of the mounted valve being shown in Figure 11, or a mounted position displaced by 180 as compared to the shown assembly.

The embodiments of the valve according to the invention as shown in Figures 1 and 2 to 8 each involve a so-called leakage-free-switching double seat valve. If locking element 5 is fixedly connected by means of bridges with valve casing part 1 or 2 then there results a valve with which a leakage-restricted switching is possible.

These connection bridges between locking element 5 and valve casing part 1 and 2 are to be provided with passage apertures which approximately correspond to the nominal 4* 49 cross section of the valve. Mode of action and function of this arrangement are known from the above mentioned S patent applications. There exists a coercive analogy resulting from the manifold aspects and ways of 9 consideration of the present problem, Figure 9 shows how a valve according to the preceding embodiments may be modified so that the seals are mounted on the side of the casing, even though only Sone seal is shown and the leakage cavity and drawn bores have been omitted. The representation on the left-hand side shows the closed position of the valve, that on the S tbspe.010/mieth.spe 91 2 19 Sr 1 korresponalerenaen waizoerclun ucr v1C:ntgcs anaCcicus unu 111111 u heitsgrades des SchlieBgliedes verschiebbar ist, und einer Dichtung bzw. Abdichtungsstelle, die entweder zwischen SchlieLB glied und Sitzbereich wirksam ist oder mit dem Verschluteil zusammen wirkt. Durch das vorgeschlagene Verfahren und die Vorrichtung zu seiner Realisierung wird unter anderem sichergestellt, daB bei einer Ventilvorrichtung der einleitend gekennzeichneten Gattung die Dichtung in anderen Stellungen als in der SchlieBstellung geschiftzt und gestiitzt ist. Dies wird unter anderem verfahrenstechnisch dadurch erreicht, daB die in der SchlieBstellung der Ventilvorrichtung eine Dichtwirkung erzeugende Beanspruchung der Dichtung bzw. Abdichtungsstelle in anderen Stellungen als in der SchlieBstellung durch das VerschluBteil hervorgerufen wird.

p I i 15 right-hand side the open position. In the closed position of the valve, seal 7, which is embedded in a casing groove la with free axial motion, is fixed in a manner known per se by means of closing element 4. For the sake of simplicity casing seal 14 required between valve casing parts 1 and 2 is shown in a very simplified manner as far as its arrangement and embedding are concerned. The nature of the modification is evident from the open position of the valve (right-hand side representation), wherein locking element 5 has substituted the position with view to seal 7 taken by the closing member 4 in the closed position. In none of the switching states shown. nor in the not shown intermdeiate states, the so-called "loose" seal 7 is exposed to the mechanical attack of the flow agent.

Seal 7 and casing groove la surrounding it become accessible to cleansing liquid in the open position of the 8 ,valve if locking element 5 is made permeable from the inner cavity of valve casing 1, 2 in the direction of seal 7 in the area of its overlapping with seal 7. For S instance, locking element 5 can be provided with a large number of openings, so that, for instance, it has the shape of a cage. However, there can also be provided i recesses passing through from the front side of locking clement 5, which recesses make possible the access of cleansing fluid between the outer surface of locking element 5 and seal 7.

If locking element 5 is of very short length in the direction of its switching mobility, so that there is tbspe.OlO/mieth.spe 91 2 19 16 given a spatial connection between the inner cavity of' valve casing 1, 2 and the walls surrounding seal 7, then there is possible in the open position of' the valve, an access of cleansing fluid from the inner cavity of valve casing 1, 2 to the sealing region in question.

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Claims (7)

1. A valve comprising a casing defining an inner cavity and a seat region, a closing member which is displaceable translatorily or rotatively in the casing, a locking element which is displaceable in the direction of motion of the closing member, sealing means comprising two seals or two sealing places which in the closed position of the valve engages said closing member and said seat region to produce a sealing effect, a leakage cavity between the seals or sealing places and at least one conduit through the closing member and connected to said leakage cavity, said seals or sealing places being engaged by said locking element, when the valve is other than closed, such that the strain on the seals or sealing places producing a sealing effect in the closed position of the valve is replaced by engagement of said seals or sealing :places with the locking element,

2. The valve of claim 1, further comprising a second conduit in said closing member and a cleansing agent feed to said second conduit,

3. The valve of claim 1 or 2 wherein said sealing means is disposed on the seat so region of the casing, said closing member interacting with Said sealing means in the closed position and being substituted by said locking element in positions other than said closed position.

4. The valve of any preceding claim, wherein said sealing means exhibits a restricted mobility in the direction of movement of said closing member.

The valve of any preceding claim, wherein said locking element in the region where it overlaps with said sealing means when the valve is not in its closed position is permeable from the inner cavity of the valve casing to the sealing means.,

6. The valve of any preceding claim, wherein said locking element is dimensioned in the direction of its displacibility such that there exists a spatial connection between the inner cavity of the valve casing and the valve casing region surrounding the ,MVS I -18- sealing means.

7. A valve substantially as hereinbefore described with reference to Figure 1 or Figures 2 and 3 or Figure 4 or Figure 5 of Figure 6 or Figure 7 or Figure 8 or Figure 9 of the accompanying drawings. DATED this 11th day of August, 1991. CARTER SMITH BEADLE Qantas House, 2 Railway Parade, Camberwell, Victoria 3124, Australia. Not: 0.. 0 M VS'