DE2257096A1 - VALVE ARRANGEMENT - Google Patents

Description

DR. MULLER-BORi; DiPL-PhYS-Un-MANlTZ DIPL-CHEM. DR. DEUFEL

DfPL-IPiG. FiNSTERWALD DlPL-TNG. GRÄMKOW

PATENT LAWYERS.

A 2259 l \, KQy. 1972

ATOlICC EHERGT Ol CANAM LIMITED '; OTTAWA, CAHADA

Valve arrangement

The invention relates to a valve arrangement.

It has already been proposed to seal a valve stem with a valve housing by means of bolts. In these proposals it was found that the useful life of the bellows for economical use with high temperature and high pressure radioactive fluids of, for example
is too limited.

for example 288 ° C. (5SO ⁰ F) and in kp / cm ² (2000 psi)

The object of the invention is to specify a valve arrangement, in which the valve stem is sealed with the valve housing by bellows and the bellows a have a longer service life than the known valve arrangements using bellows seals,

3G9829 / Ö3S9

Dr. Müller-Bort Dr. Manltz Dr. Deufel · Dlpl.-Inff. Flneferwald. Dlpl.-Ing. Grämkow

Braunschweig, Am Bürgerparktt Munich β 22 .Robert Koch StraBe t 7 Stu "aart-Bad Cannstatt, Marktstrafle

Telephone (0531) 7388T _Tetef0 " _{(0811) 283β45 | Τβ} | _βχ 5.J _{2050 mbpat} Telephone »711) 587281

- Bank: Zentraikaes · Bayer. Volksbanken, Munich, account no. 8822 Post check: Munich 954B5

A valve arrangement according to the invention has a Housing with a valve stem seat that serves as a sealing surface around a transport fluid channel through the housing to seal and a valve stem bore that is extends inwardly through the housing and ends at the valve stem seat, with an inner portion of the valve stem bore has a relatively larger cross-section than the remaining part, around an annular cavity to form, which extends inwardly from a constricted part, a valve stem which constricts in the Part is slidable and extends along the valve stem bore to oppose a sealing surface on the valve stem to seal the valve stem seat, a seal which sealing the valve stem in the narrowed part, three bellows in the annular cavity in series along this and around the valve stem, of which bellows an inner one at the inner end with one Part of the valve stem adjacent to the sealing surface is sealed, an outer end with the inner bellows and an adjacent end of an intermediate bellows is sealed to the housing, an outer end of the intermediate bellows and an outer bellows are sealed with the valve stem and an outer end of the outer bellows is sealed to the housing, so that the three bellows the annular cavity in four Seal volume, the first of which is a transport fluid cavity is around the inner bellows and emanates from the transport fluid channel, a second volume through a primary buffer fluid cavity within the inner bellows and the intermediate bellows, a third volume is formed by a secondary buffer fluid cavity, is formed around the intermediate bellows and the outer bellows and the fourth volume is formed by a control fluid cavity that extends

309829 / 03S9

from the inside of the outer bellows to the narrowed one Part extends, a filling channel for the primary buffer fluid, der.sich through the housing to the primary buffer fluid cavity extends, a filling channel for the secondary buffer fluid, which extends through the housing to secondary.buffer fluid cavity extends, a control fluid filling channel, which extends through the housing to the control fluid cavity extends, a valve actuator connected to the valve stem to move it, so that its sealing surface is moved in contact with the valve stem seat or away from it by means of the control fluid and means for supplying pressurized control fluid to the control fluid cavity and for actuating the valve actuator with essentially the same pressure.

The accompanying drawing shows, for example, an embodiment of a valve arrangement according to the invention shown in side view and in section.

As can be seen, the valve arrangement has a housing 1 with a valve stem seat 2, which serves as a sealing surface for sealing a transport fluid channel 4 through the housing 1, and with a valve stem bore 6 which extends inwardly through the housing 1 and ends at the valve stem seat 2, with an inner part of the valve stem bore 6 is of relatively larger cross-section than the remaining part, in order to form an annular cavity 8 which extends inwardly from a narrowed part 10. The valve stem 12 has a spindle part 13 which is slidable in the narrowed part 10 and extends along the valve stem bore 6 in order to seal a sealing surface 14 against the valve stem seat 2. A seal, which has the form of an O-ring _v seal 16, seals the valve stem 12 in the constricted

3G9829 / 03S9

Part 10 from · Three bellows 18, 20 and 22 are arranged in the annular cavity 8 and are connected one behind the other along this and around the valve stem 12. The inner bellows, designated 18, is sealed at the inner end 2H by a collar 26 against a part of the valve stem 12 adjacent to the sealing surface If. The outer end 28 of the inner bellows 16 and the adjacent end 30 of the intermediate bellows designated by 20 are sealed against a collar part 32 of the housing 1; the outer end 3t of the intermediate bellows 20 and the inner, adjacent end 36 of the outer bellows designated by 22 are sealed against the valve stem 12 by a collar 38.The outer end 40 of the outer bellows 22 is sealed against a collar part 42 of the housing 1. By sealing the ends of the bellows 18, 20 and 22 in the manner described, the annular cavity 8 is sealed in four volumes. The first volume is a transport fluid cavity HH uv around the inner bellows 18 and emanates from the transport fluid channel 4. The second volume is a primary buffer fluid cavity HS within the inner bellows 18 and the intermediate bellows 20. The third volume is a secondary buffer fluid cavity H 8 around the intermediate bellows 20 and the outer bellows 22 around. The fourth volume is a control fluid cavity 50 within the outer bellows 22 and adjacent to the constricted portion 10. A fill channel 52 for the primary buffer fluid extends through the collar portion 32 of the housing 1 to the primary buffer fluid cavity 46. A fill channel 54 for the secondary buffer fluid extends extends through a flanged portion 56 of the housing to the secondary buffer fluid cavity 48. A control fluid fill passage 58 extends through the housing 1. A valve actuator, indicated generally at 60, is connected to the valve stem 12 for closing

309829/0359

move so that the sealing surface It with the help of the control fluid in support of the valve stem seat 2 or of this way can be moved. A generally designated 62 device is used to stand under pressure To supply control fluid to the control fluid cavity 50 and the valve actuator 60 with essentially the press the same pressure.

The housing 1 is formed by a part 64 containing a transport fluid, the collar part 32, a part 66 containing a secondary buffer fluid, an annular seat 68, the collar part 42, a part 70 containing a control fluid and an end plug 72. The part 64, the collar part 32 and the part 66 are clamped together and sealed against each other, for which purpose clamping bolts and nuts, a pair of which are shown and _{denoted by 74 s} 76, and O-ring ^V seals 78 and 80 are used. The part 66, the annular seat 68, the collar part 42 and the part 70 are clamped together and sealed against one another by clamping bolts and nuts, a pair of which are shown and designated by 82, 84, and seals 86 and 88. The part 70 and the end plug 72 are clamped together by bolts 90 and sealed against one another by an O-ring seal 92 «'

The valve stem seat 2 is an inclined, concave annular surface which faces the valve stem 12, and the sealing surface 14 is an oblique convex annular one Area for contact with the valve stem seat.

The transport fluid channel 4 in the part 64 is through two Parts formed by an inlet 94 and an outlet 96 which are offset in the longitudinal direction such that the outlet 96 is above the inlet

309829/0359

and the valve stem seat 2 lies between them The valve stem 12 is slidable in the collar part 32 in which a channel 98 for the primary buffer fluid is provided which extends along the valve stem 13 and the primary buffer fluid within the inner bellows 18 with the primary buffer fluid inside of the intermediate bellows 20 connects to one another. The valve stem 12 is also slidable in the collar part 4 2, in which a control fluid channel 100 is provided which extends along the valve stem 12 in order that Control fluid within the outer bellows 22 with the To connect control fluid to the narrowed part 10

The part 70 has a cylindrical cavity 102, which contains the valve actuator 60, and a control fluid channel 104 which is connected to that part of the Cavity 102, which is located below the valve actuator 60, is in communication. In the end plug 72 is a control fluid channel 106 with that part of the cavity 102 in connection, which is above of the valve actuator 60 is located. The valve actuator is formed by a piston 108 » which is slidable in the cylindrical cavity 102 in the longitudinal direction of the valve stem 12 and on the spindle part 13 is attached, with an O-ring seal 110 den Piston 108 seals in the cylindrical cavity 102

The device 6 2 for the supply of the Steuerfluxda to Control fluid cavity 50 and for actuating the valve actuator 60 at substantially the same pressure has a source of control fluid under pressure 112, which is connected by a pipe 11t to a four-way valve 116, furthermore a discharge

309329/0359

Pipeline 118, which is connected to the four-way valve 116, pipelines 120 and 122, which the
Connect four-way valve 116 to channels 1OH and 106, uhd a pipeline 121 which connects pipeline IW to channel 58. A drain pipe 126 is connected to the valve 116.

In operation, when the valve arrangement is in the state shown in the drawing, the valve stem 12 is in the closed position in which a flow of transport fluid from the inlet 94 to the outlet 96 is prevented. When the valve stem is in the closed position, the top of the piston is 108
pressurized by control fluid from source 112 via conduit 114, valve 116 and conduit 122. The lower side of the piston 108 is connected to the discharge pipe 126 via the pipe 120 and the valve 116
tied together.

The control fluxdhdhlraum 50 is also pressurized from the source 112 via the conduits 114 and 124, which in turn pressurizes the secondary buffer fluid in the cavity 48 for this, whereupon the primary buffer fluid in the cavity 46 for this is pressurized, and finally the transport fluid in the transport fluid cavity 44 is under pressure load · the control fluid, the secondary buffer fluid, the
primary buffer fluid and the control fluid in control fluid cavity 44 are therefore all under substantially the same pressure. If one of the bellows 18, 20 or 22
damaged, any leakage occurs as a leakage
through the bellows,

When the valve stem 12 moves to the open position
is to be operated, the valve 116 is actuated to control fluid

309829/0359

under pressure via the pipe 120 of the underside of the Plunger 108 feed and the top of plunger 108 with drain pipe 126 through pipe 122 to connect · When the valve stem 12 moves upwards, the bellows 18 is closed somewhat, during the Bellows 20 is opened by the same small amount, so that the volume of the primary buffer fluid cavity 4 6 remains essentially constant * The bellows 22 is closed by the same amount that the bellows is opened, so that the volume of the cavity 48 for the secondary buffer fluid remains essentially constant "

The valve assembly described therefore did the following Advantages:

1) The contribution of the pressure of the fluids to the state of tension in the bellows 18, 20 and 22 can practically be eliminated because the pressures inside and outside the bellows 18, 20 and 22 are largely approximated to one another.

2) The lack of pressure drop across the bellows 18, 20 and 22 allows for versatility in the choice of bellows 18, 20 and 22 in terms of the materials used and the number of layers required. Eb can add weight to the desirable properties of the materials instead of their strength.

3) The novel arrangement of the bellows 18, 20 and 22 makes it possible that even two of the bellows fail before replacement is required.

Ό The fluid inside and outside each bellows 18,

309829/0359

20 and 22 cause hydraulic damping of any Resonance vibrations, which may be caused by the transport fluid or by an attached vibrations generated machine can be excited.

5) In addition, the potential frictional wear between the bellows 18, 20 and 22 and the valve stem 12 as well as between the bellows 18, 20 and 22 and the housing 1 due to the lubricating effect of the fluid

6) Oa the complete unit is hermetically sealed, i.e. no dynamic seals are used no spacer seal required for a full failure to prevent·

30982i /

Claims (1)

Patent claims ι Valve arrangement, characterized by a housing (1) with a valve stem seat (2) which has a sealing surface for sealing a transport fluid channel (1) through the housing (1), and a valve shaft bore (8), which extends inwardly through the housing (1) and terminates at the valve stem seat (2), where «is the inner part of the valve stem bore (6) has a relatively larger cross-section than the remaining part, to form an annular cavity (8) extending inwardly from a narrowed part (10), a valve stem (12) which is slidably arranged in the narrowed part (10) and extends along the valve Bore (6) extends to seal a sealing surface (11) on the valve stem (12) against the valve stem seats (2), a seal (18) which the valve stem (12) in the narrowed part UO) seals three bilges (18, 20, 22) in the annular cavity (8) and in Series connection, by its length and by the Valve stem (12), of which the inner bellows (18) is sealed at the inner end (2H) on a part of the valve stem (12) adjacent to the sealing surface (11), the outer end (28) of the inner bellows (18) and the adjacent end of the ζwiec-henliegend Bellows with the housing «(1) are sealed, the outer End (31) of the intermediate bellows (20) and the adjacent inner end (36) of the outer bellows (22) is sealed with the valve stem (12) and the outer End (10) of the outer bellows (22) with the housing (J) 3U9828 / 0359 is sealed so that the three bellows (18 _e 20, 22 j seal the annular cavity (18) to four volumes, a first volume forms a transport fluid cavity (H4) around the inner bellows (18) and with the transport fluid channel (U) communicates, a second volume forms a primary buffer fluid cavity (46) within the inner bellows (18) and the intermediate bellows (20), a third volume forms a secondary buffer fluid cavity around the intermediate bellows (20) and the outer bellows (22) forms, and the fourth volume is a control fluid cavity (50) which extends from inside the outer bellows (22) to the constricted part (10), a filling channel (5 2) for the primary buffer fluid through the housing (1) to the primary buffer fluid cavity (46), a filling channel (54) for the secondary buffer fluid extends through the housing (1) to the secondary buffer fluid cavity (48), a control fluid filling channel (58) which extends through the housing (1) to the Ste extends uerfluidhohlraum (50), a valve actuating · organ (60) which is connected to the valve stem (12) ₉ to move the latter and thereby the sealing surface (11) or on that bearing on the valve stem seat (2) by means of the control fluid . to move away from this seat and means for supplying pressurized control fluid to the control fluid cavity (50) and for actuating the valve actuator (60) at essentially the same pressure, 2, valve arrangement according to claim 1, characterized in that the valve actuating member (60) by a piston 309829/0359 2257036 (108) is formed, which is attached to the valve stem (3.2) and is slidable in a cylindrical part '(102) of the housing, which extends from the narrowed part (10) to the outside, and the .einrichtung (62), through which the control fluid can be pressurized, comprises a control fluid pressure source 012), further a valve (116) which connects the pressure source (112) with parts of the cylindrical extension (102) on each side of the piston (103), and Medium, "reach the pressure source (112) with the control fluid hollow" (SO.) Connect. 3. Valve arrangement according to claim 1, characterized in that the valve stem seat (2) has an inclined, concave *. is an annular surface facing the valve stem (12), while the sealing surface (I ¹ O on the valve stem (12) is an inclined, convex annular fleece to rest on the valve stem seat (2) <4 «Valve arrangement according to claim 1, characterized in that that two collars are provided on the valve stem (12), the inner end (2%) of the inner bellows (IS) on one (26) of the collar is attached to the valve stem (12) and the outer end (3 * 0 of the intermediate Bellows (20) and the inner adjacent end (36) of the outer bellows (22) on the other collar (If) are attached to the valve stem (12). Valve arrangement according to Claim 1, characterized in that the housing has parts which can be separated from one another, namely one containing the transport fluxd. Portion (64), a collar portion (32) slidably attached to the valve stem (12), a first. Buffer fluid channel (98) is provided between the collar (32) and the valve stem (12), the outer one. end (28) of the inner bellows (18) and "aas adjacent end (26) of the inner bellows (18) are attached to the collar part (26), a containing the secondary buffer fluid Part (66), a part (70) containing the control fluid and an end cap (72). JUJ82970359 Lee r s e 11 e