US3734134A - Valve arrangement having two valves in a common housing and use of the arrangement in a vapor generating and utilizing plant - Google Patents
Valve arrangement having two valves in a common housing and use of the arrangement in a vapor generating and utilizing plant Download PDFInfo
- Publication number
- US3734134A US3734134A US00193224A US3734134DA US3734134A US 3734134 A US3734134 A US 3734134A US 00193224 A US00193224 A US 00193224A US 3734134D A US3734134D A US 3734134DA US 3734134 A US3734134 A US 3734134A
- Authority
- US
- United States
- Prior art keywords
- valve
- gear
- valve stem
- stem
- closure body
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000012530 fluid Substances 0.000 claims abstract description 22
- 238000006073 displacement reaction Methods 0.000 claims description 4
- 230000001105 regulatory effect Effects 0.000 abstract description 8
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000011144 upstream manufacturing Methods 0.000 description 3
- 230000001419 dependent effect Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 241000282320 Panthera leo Species 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K39/00—Devices for relieving the pressure on the sealing faces
- F16K39/02—Devices for relieving the pressure on the sealing faces for lift valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D17/00—Regulating or controlling by varying flow
- F01D17/10—Final actuators
- F01D17/12—Final actuators arranged in stator parts
- F01D17/14—Final actuators arranged in stator parts varying effective cross-sectional area of nozzles or guide conduits
- F01D17/141—Final actuators arranged in stator parts varying effective cross-sectional area of nozzles or guide conduits by means of shiftable members or valves obturating part of the flow path
- F01D17/145—Final actuators arranged in stator parts varying effective cross-sectional area of nozzles or guide conduits by means of shiftable members or valves obturating part of the flow path by means of valves, e.g. for steam turbines
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K25/00—Details relating to contact between valve members and seats
- F16K25/04—Arrangements for preventing erosion, not otherwise provided for
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/8593—Systems
- Y10T137/87096—Valves with separate, correlated, actuators
- Y10T137/87121—Coaxial stems
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/8593—Systems
- Y10T137/87265—Dividing into parallel flow paths with recombining
- Y10T137/87378—Second valve assembly carried by first valve head
Definitions
- the invention also relates to the use of Jan. 28, 1969 Switzerland ..001240/69 the valve arrangement in a steam or vapor generating plant for facilitating starting thereof.
- This invention relates to a valve arrangement comprising a first closing element which, in combination with a suitable seat, forms a first valve.
- the invention also relates to the combination of the valve arrangement according to the invention with a steam generating plant.
- the valve arrangement according to the invention is characterized by the provision of a second closing element which, with a passage for an operating fluid in the aforesaid first closing element forms a second valve arranged in parallel relation with the first valve with respect to fluid flow, the second valve being adjustable independently of the first valve.
- a second closing element which, with a passage for an operating fluid in the aforesaid first closing element forms a second valve arranged in parallel relation with the first valve with respect to fluid flow, the second valve being adjustable independently of the first valve.
- An object of the invention is the use of the valve arrangement according to the invention in lieu of a conventional parallel arrangement of a regulating valve for great pressure drops, particularly critical pressure drops, and a separate stop valve having a greater flow area than that of said regulating valve.
- valve arrangement according to the invention is the placement of two valves in a single housing, a smaller space requirement, and the simplification of the piping for the operating fluid in a plant equipped with the new valve arrangement since no by-pass line containing the smaller valve is required for the larger valves.
- the advantage of the use of the valve arrangement according to the invention in combination with a critical pressure steam or vapor generator will now be described. At a critical pressure drop of the operating fluid in a valve, the fluid attains the speed of sound whereby strong vibrations and/or cavitations may occur which destroy the valve.
- the smaller one of the two valves in a common casing may be built as a shut-off and regulating valve and very strong, i.e., suitable for great pressure drops, for regulating the flow of the operating fluid until the pressure at the valve has reached a value permitting opening the larger valve which is built for a considerably smaller, subcritical pressure drop.
- the smaller valve may be made as small as is possible considering the operating conditions of the plant wherein it is used.
- the larger valve has a large flow area and operates at little pressure drop. It may be constructed as an open closed or as a stop valve, eventually provided with course positioning means instead of with a continuously operating control drive.
- FIG. I is a longitudinal part-sectional view of a valve arrangement according to the invention.
- FIG. 2 is a simplified, part-sectional layout of a forced-flow steam or vapor generating plant comprising a valve arrangement according to the invention.
- numeral 1 designates a housing having an inlet 2 and an outlet 3 for an operating fluid.
- A. first valve stem 6 is placed in a guide element 4 which also forms the closure of the valve housing 1 and is sealingly connected to the valve housing by means of an autoclave closure 5.
- the stem 6 extends through a stuffing box 7 and is connected to a threaded spindle by means of two disconnectable coupling elements 8 and 9.
- the spindle 10 is supported by a nut element which is supported by a support element 18 whereto the nut element 15 is connected by two ballbearings 16 and 17. Rotation of the spindle 10 is prevented by a forked guide lever 19 which is connected by a link 20 to eyes 21 attached to the support element 18.
- An internally toothed gear 23 is wedged to an extension sleeve 22 of the nut element 15, a gear engaging the internal teeth 24 of the gear 23.
- the gear 25 is rigidly connected to an adjacent gear 27 by means of a pin 26, the gear 27 meshing with a stationary internal gear 28.
- the number of teeth of the gear 25 differs from that of the gear 27 by one.
- the gears .25 and 27 are placed on a pin 31 whose ends rest in flanges 32 and 33, respectively, of an annular support 34. There are four pins 31 with gears mounted thereon which are supported by the support 34 at 90 angular spacing.
- the upper flange 33 of the support 34 is provided with internal teeth 35 meshing with teeth of a pinion 36 of a servomotor 37 and with the teeth of a pinion, not shown, of a second servomotor 38.
- the lower end of the first valve stem 6 has a closure body 40 connected thereto which, by means of a seat 41 provided in the valve housing 1, forms a first valve 42.
- the closure body 40 has an extension provided with openings 43, 44 and 45 affording passage of the operating fluid.
- the first valve stem 6 is provided with a longitudinal bore 46 wherein a second valve stem 47 is guided, the upper end of the second valve stem being guided in a stuffing box 48, the lower end 49 of the stem 47 being of increased diameter to snugly fit into the bore 46.
- the large diameter end of the second valve stem forms a closure body capable of sitting on a seat 50 in the opening 43 for forming a second valve 51.
- the second valve stem 47 is connected to a push rod 58 of a servomotor 59 having a linear operating stroke, by means of a releasable coupling 55, a spindle 56, and a releasable coupling 57.
- the stem 56 is vertically movable in the threaded spindle 10.
- the servomotor 59 is rigidly connected to the spindle 10.
- the servomotor 59 is provided with a handwheel 60 for manual operation of the push rod 58, if desired. Since the servomotor 59 is rigidly connected to the stationary threaded spindle 10, the second valve stem 47 can be moved independently of the first stem 6 so that the valve effects of the valves 42 and 51 are independent of one another.
- the two valves may have a common drive. In this case the position of one valve is dependent on the position of the second valve; the valve effects, however, of the two valves are separated.
- the flow area of the first valve 42 is large and the pressure drop across this valve is small. It may be designed as a shut-off valve which is either open or closed.
- the second valve 51 has a much smaller flow area and may be designed as a shut-off and regulating valve. The second valve is built very strong and affords control of the rate of flow of operating fluid at a great pressure drop, for example a pressure drop which is equal to or greater than the critical pressure drop.
- numeral .65 designates a feedpump, 66 a feedwater valve, 67 a feedwater heater, 68 an economizer heating surface 69 a circulating pump, 70 an evaporator, 71 the valve arrangement according to the invention comprising partial valves BT and BTB, 72 a superheater, 73 a turbine inlet valve, 74 a high pressure turbine, 75 a reheater, 76 a low pressure turbine, 77 a condenser, 78 a condensate pump, 79 a condensate preheater, 80 a feedwater container, 81 a water circulating pipe, 83 a liquid-vapor separator having a liquid space and a vapor space, 82 a pressure control valve in a pipe connecting the separator to a conduit 87 receiving vapor from the evaporator 70,
- valve arrangement 71 which is in parallel relation to the separator 83, is to prevent flow of water from the evaporator 70 through the conduit 87 into the superheater 72, when the plant is started.
- valves BT, BTB and the valve 82 which is set for a predetermined pressure, for example 70 kglcm are initially closed.
- the turbine inlet valve 73 is partly open.
- the valve 82 opens and operating fluid flows into the separator 83.
- the separated vapor or steam flows through the throttle valve 86 into the superheater 72.
- the steam superheated in the superheater 72 flows through the turbine inlet valve 73 into the high pressure turbine 74.
- the valve 82 is gradually adjusted, by means not shown, to maintain a gradually increased pressure until, after a predetermined temperature, for example 290 C, has been reached by the steam generated in the evaporator 70, a constant pressure, for example 245 kg/cm is maintained upstream of the valve 82.
- a predetermined temperature for example 290 C
- a constant pressure for example 245 kg/cm
- the pressure of 245 kg/cm at the outlet of the steam generator or evaporator 70 is retained when changing operation from through the separator 83 to operation through the valve BTB. Combustion and feedwater supply are further increased and the output of the turbine is increased accordingly.
- the turbine inlet valve 73 remains in its initial position.
- critical pressure drop occurs therein.
- the pressure upstream of the turbine inletvalve 73 increases and the pressure drop across the valve BTB decreases. If the pressure drop across the valve is below the critical value, i.e., if the pressure upstream of the valve [is 245 kg/cm, the valve BT may be opened.
- valve ET When the plant operates at full load the valve ET is fully opened, whereas the valve BTB may remain open or may close dependent on the control arrangement.
- valve BTB When the plant operates at full load the valve ET is fully opened, whereas the valve BTB may remain open or may close dependent on the control arrangement.
- a valve system comprising a coaxial arrangement of a first valve and a second valve in parallel relationship with respect to a flow of fluid therethrough, said first valve comprising a first valve stem having a first closure body thereon and a first valve seat, said first valve stem being secured against rotation, said second valve comprising a second valve stem and a second valve seat on said first closure body, said second valve stem being slidably mounted in said first valve stem and drive means connected to said first valve and including a threaded portion on said first valve stem, a rotatably mounted nut element in meshing engagement with said threaded portion, said nut element having an internally toothed gear thereon, a first gear engaging said internally toothed gear, a second gear rigidly connected to said first gear and being in meshing engagement with a stationary internal gear having a number of teeth differing by at least one from that of the second gear, a support connected with said nut element rotatably mounting said first gear and said second gear on a common axis thereof, said support having an internally toothed
- a valve system comprising a coaxial arrangement of a first valve and a second valve in parallel relationship to each other with respect to a flow of fluid therethrough, said first valve comprising a first valve stem having a first closure body thereon and a first valve seat, said first valve stem being secured against rotation, said second valve comprising a second valve stem and a second valve seat on said first closure body, said second valve stem being slidably mounted in said first valve stem and drive means including a servomotor connected to said second valve stem for actuating said second valve independently of said first valve, said drive means being connected with said first valve stem of said first valve to move with said first valve stem during displacement of said first valve stem relative to said first valve seat and a second drive means including at least one servomotor for actuating said first valve.
- a valve system comprising a coaxial arrangement of a first valve and a second valve in parallel relationship to each other with respect to flow a fow of fluid therethrough, said first valve comprising a first valve stem having a first closure body thereon and a first valve seat, said second valve comprising a second valve stem and a second valve seat on said first closure body, said second valve 'stem being slidably mounted in said firstvalve stem, and drive means including a servomotor connected to said second valve stem for actuating said second valve independently of said first valve, said drive means being connected with said first valve stem of said first 'valve to move with said first valve stem during displacement of said first valve stem relative to said first valve seat and a second drive means including at least one servomotor for actuating said first valve.
- a valve system comprising a coaxial arrangement of a first valve and a second valve in parallel relationship with respect to a flow of fluid therethrough, said first valve comprising a first valve stem having a first closure body thereon and a first valve seat, said second valve comprising a second valve stem and a second valve seat on said first closure body, said second valve stem being slidably mounted in said first valve stem and drive means connected to said first valve and including a threaded portion on said first valve stem, a rotatably mounted nut element in meshing engagement with said threaded portion, said nut element having an internally toothed gear thereon, a first gear engaging said internally toothed gear, a second gear rigidly connected to said first gear and being in meshing engagement with a stationary internal gear having a number of teeth differing by one from that of the second gear, a support connected with said not element rotatably mounting said first gear and said second gear on a common axis thereof, said support having an internally toothed gear and at least two servomotors provided with
- a valve system comprising a coaxial arrangement with drive pinions meshing with said toothed gear.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Control Of Turbines (AREA)
- Engine Equipment That Uses Special Cycles (AREA)
- Control Of Steam Boilers And Waste-Gas Boilers (AREA)
- Multiple-Way Valves (AREA)
- Lift Valve (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH124069A CH503930A (de) | 1969-01-28 | 1969-01-28 | Ventilvorrichtung und deren Verwendung |
Publications (1)
Publication Number | Publication Date |
---|---|
US3734134A true US3734134A (en) | 1973-05-22 |
Family
ID=4205748
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00193224A Expired - Lifetime US3734134A (en) | 1969-01-28 | 1971-10-27 | Valve arrangement having two valves in a common housing and use of the arrangement in a vapor generating and utilizing plant |
Country Status (9)
Country | Link |
---|---|
US (1) | US3734134A (enrdf_load_stackoverflow) |
BE (1) | BE744999A (enrdf_load_stackoverflow) |
CA (1) | CA945980A (enrdf_load_stackoverflow) |
CH (1) | CH503930A (enrdf_load_stackoverflow) |
DE (1) | DE1904971B2 (enrdf_load_stackoverflow) |
ES (1) | ES375551A1 (enrdf_load_stackoverflow) |
FR (1) | FR2031232A5 (enrdf_load_stackoverflow) |
GB (1) | GB1254262A (enrdf_load_stackoverflow) |
SE (1) | SE357422B (enrdf_load_stackoverflow) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4041979A (en) * | 1975-07-25 | 1977-08-16 | Sulzer Brothers Limited | Control valve having independently driven valves |
US4041980A (en) * | 1975-07-25 | 1977-08-16 | Sulzer Brothers Limited | Control valve having two independently driven valves |
US4060453A (en) * | 1975-04-30 | 1977-11-29 | Kraftwerk Union Aktiengesellschaft | Nuclear reactor installation |
US4066498A (en) * | 1974-03-01 | 1978-01-03 | Kraftwerk Union Aktiengesellschaft | Shut-off and safety device for a live steam line in a pressurized water reactor |
US4092214A (en) * | 1975-08-13 | 1978-05-30 | Kraftwerk Union Aktiengesellschaft | Nuclear reactor installation |
US4697615A (en) * | 1985-04-30 | 1987-10-06 | Asahi Glass Company Ltd. | Butterfly valve for controlling high-temperature fluid |
US5052430A (en) * | 1990-06-11 | 1991-10-01 | G. H. Bettis | Valve actuator |
RU2449196C2 (ru) * | 2010-07-02 | 2012-04-27 | Федеральное Государственное Унитарное Предприятие "Государственный научно-производственный ракетно-космический центр "ЦСКБ-Прогресс" (ФГУП "ГНПРКЦ "ЦСКБ-Прогресс") | Вентиль высокого давления |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2534279C2 (de) * | 1975-07-31 | 1984-09-06 | Deutsche Babcock Ag, 4200 Oberhausen | Ventil |
GB2193295A (en) * | 1986-07-03 | 1988-02-03 | Hattersley Newman Hender | Valves |
DE59103885D1 (de) * | 1990-09-29 | 1995-01-26 | Siemens Ag | Stellventil für dampfförmige oder flüssige Medien. |
SE467223B (sv) * | 1990-11-19 | 1992-06-15 | Tour & Andersson Ab | Ventil foer tvaa- eller flervaegs floedesreglering |
GB2268791A (en) * | 1992-07-15 | 1994-01-19 | Rexson Systems Limited | Dispensing valve |
-
1969
- 1969-01-28 CH CH124069A patent/CH503930A/de not_active IP Right Cessation
- 1969-02-01 DE DE19691904971 patent/DE1904971B2/de not_active Withdrawn
-
1970
- 1970-01-17 ES ES375551A patent/ES375551A1/es not_active Expired
- 1970-01-21 SE SE00720/70A patent/SE357422B/xx unknown
- 1970-01-26 CA CA073,061A patent/CA945980A/en not_active Expired
- 1970-01-27 GB GB3919/70A patent/GB1254262A/en not_active Expired
- 1970-01-27 BE BE744999D patent/BE744999A/xx not_active IP Right Cessation
- 1970-01-27 FR FR7002793A patent/FR2031232A5/fr not_active Expired
-
1971
- 1971-10-27 US US00193224A patent/US3734134A/en not_active Expired - Lifetime
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4066498A (en) * | 1974-03-01 | 1978-01-03 | Kraftwerk Union Aktiengesellschaft | Shut-off and safety device for a live steam line in a pressurized water reactor |
US4060453A (en) * | 1975-04-30 | 1977-11-29 | Kraftwerk Union Aktiengesellschaft | Nuclear reactor installation |
US4041979A (en) * | 1975-07-25 | 1977-08-16 | Sulzer Brothers Limited | Control valve having independently driven valves |
US4041980A (en) * | 1975-07-25 | 1977-08-16 | Sulzer Brothers Limited | Control valve having two independently driven valves |
US4092214A (en) * | 1975-08-13 | 1978-05-30 | Kraftwerk Union Aktiengesellschaft | Nuclear reactor installation |
US4697615A (en) * | 1985-04-30 | 1987-10-06 | Asahi Glass Company Ltd. | Butterfly valve for controlling high-temperature fluid |
US5052430A (en) * | 1990-06-11 | 1991-10-01 | G. H. Bettis | Valve actuator |
RU2449196C2 (ru) * | 2010-07-02 | 2012-04-27 | Федеральное Государственное Унитарное Предприятие "Государственный научно-производственный ракетно-космический центр "ЦСКБ-Прогресс" (ФГУП "ГНПРКЦ "ЦСКБ-Прогресс") | Вентиль высокого давления |
Also Published As
Publication number | Publication date |
---|---|
CA945980A (en) | 1974-04-23 |
ES375551A1 (es) | 1972-07-01 |
CH503930A (de) | 1971-02-28 |
FR2031232A5 (enrdf_load_stackoverflow) | 1970-11-13 |
SE357422B (enrdf_load_stackoverflow) | 1973-06-25 |
DE1904971A1 (de) | 1970-08-06 |
BE744999A (fr) | 1970-07-27 |
GB1254262A (en) | 1971-11-17 |
DE1904971B2 (de) | 1972-03-23 |
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