EP0144326A4 - Gate valve. - Google Patents
Gate valve.Info
- Publication number
- EP0144326A4 EP0144326A4 EP19840900169 EP84900169A EP0144326A4 EP 0144326 A4 EP0144326 A4 EP 0144326A4 EP 19840900169 EP19840900169 EP 19840900169 EP 84900169 A EP84900169 A EP 84900169A EP 0144326 A4 EP0144326 A4 EP 0144326A4
- Authority
- EP
- European Patent Office
- Prior art keywords
- seat carrier
- gate
- seal
- valve body
- valve
- 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.)
- Withdrawn
Links
- 239000002184 metal Substances 0.000 claims abstract description 20
- 229910052751 metal Inorganic materials 0.000 claims abstract description 20
- 230000000295 complement effect Effects 0.000 claims abstract description 12
- 238000007789 sealing Methods 0.000 claims description 15
- 239000012530 fluid Substances 0.000 claims description 12
- 239000000463 material Substances 0.000 claims description 9
- 125000006850 spacer group Chemical group 0.000 claims description 9
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims description 6
- 210000005069 ears Anatomy 0.000 claims description 6
- 238000007747 plating Methods 0.000 claims description 6
- 230000003247 decreasing effect Effects 0.000 claims description 3
- 238000010276 construction Methods 0.000 description 7
- 239000011248 coating agent Substances 0.000 description 4
- 238000000576 coating method Methods 0.000 description 4
- 238000011144 upstream manufacturing Methods 0.000 description 3
- KKEBXNMGHUCPEZ-UHFFFAOYSA-N 4-phenyl-1-(2-sulfanylethyl)imidazolidin-2-one Chemical compound N1C(=O)N(CCS)CC1C1=CC=CC=C1 KKEBXNMGHUCPEZ-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000003754 machining Methods 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- BFKJFAAPBSQJPD-UHFFFAOYSA-N tetrafluoroethene Chemical group FC(F)=C(F)F BFKJFAAPBSQJPD-UHFFFAOYSA-N 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- 229910000792 Monel Inorganic materials 0.000 description 1
- 239000011324 bead Substances 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- OANFWJQPUHQWDL-UHFFFAOYSA-N copper iron manganese nickel Chemical compound [Mn].[Fe].[Ni].[Cu] OANFWJQPUHQWDL-UHFFFAOYSA-N 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- 229920002313 fluoropolymer Polymers 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 238000005495 investment casting Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 238000004881 precipitation hardening Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
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
- F16K3/00—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing
- F16K3/02—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with flat sealing faces; Packings therefor
- F16K3/0227—Packings
- F16K3/0236—Packings the packing being of a non-resilient material, e.g. ceramic, metal
-
- 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
-
- 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
- F16K3/00—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing
- F16K3/30—Details
- F16K3/316—Guiding of the slide
Definitions
- the present invention provides a gate valve that utilizes metallic sealing and is of unitized construction.
- the valve includes a valve body that has the usual through passage for the fluid that is to be controlled and has a bore for receiving the internal portions of the valve with this bore intersecting and traversing the through passage.
- the portion of the bore adjacent to the through passage is conical and there is received in this conical region a seat carrier.
- This seat carrier has a through passage in alignment with the passage in the housing and a conical surface complementary with that of the housing bore.
- a seal is provided between the seat carrier and the body by means of an annular metallic seal member generally coaxial of these through passages and positioned at each end of the through passage in the seat carrier.
- the seat carrier is forced into its proper position in the valve body by means of assembling the valve and particularly the bolting down of the valve bonnet. This action squeezes the seal members or, in other words, energizes them into sealing position. When thus energized, the seal members maintain the conical surfaces of the seat carrier and the valve body in spaced relation.
- the action of forcing the seat carrier into position in the valve body causes compression of the seat carrier (deformation within the elastic l mit) and tensioning of the valve body ⁇ deformation within the elastic limit) the result of which is to provide a resilient bias urging the seal member into sealing position notwithstanding expansion and contraction of these valve parts due to temperature and pressure variations.
- the gate is loosely received within a suitable rectangular recess extending through the seat carrier and a seat arrangement is provided between the gate and the seat carrier so as to provide a metal-to-metal seal through the action of the controlled fluid against the gate.
- valve assembly is such that upon removal of the valve bonnet from the valve body, the entire internal valve assembly is removed as a unit.
- Figure 1 is a view partially in section of the gate valve of the invention with the gate in the closed position;
- Figure 2 is a similar view with the gate in the open position;
- Figure 3 is an exploded view of the gate valve of the invention.
- Figure 4 is a perspective view of the seal loading spacers that form a part of the valve
- Figure 5 is a view of the gate with a phanthom view of the spacers as they are positioned relative to the gate in the - valve
- Figure 6 is a perspective view of the seat carrier and one of the metallic seal rings
- Figure 7 is an enlarged section of the gate and the seat carrier with the gate in the closed position;
- Figure 8a is a sectional view of the ring taken along line 8- 8 of- Figure 6;
- Figures 8b, 8c, and 8d are views similar to Figure 8a by showing modified seal ring constructions.
- Figure 9 is an enlarged fragmentary sectional view of seal ring in position and energized.
- Figure 10 is a perspective view of another preferred • embodiment of the seat carrier and one of the metallic seal rings.
- Figure 11 is an enlarged fragmentary sectional view of the seat carrier of Figure 10 with the carrier forced down into its operative position in the valve body and with the seal ring energ zed.
- Figure 12 is an elevational view of still another preferred embodiment of seat carrier having a metallic sleeve insert to prevent inward distortion of the seal ring.
- Figure 13 is a sectional view taken from line 13-13 of Figure 12.
- Figure 14 is an elevational view of a further preferred embodiment of seat carrier where the seal ring is formed integral with the seat carrier.
- Figure 15 is a sectional view taken from line 15-15 of Figure 14. Detailed Description of the Preferred Embodiment
- a metallic gate val e having a valve body 10 with a through passage 12 therein and the usual flanges 14 for securing the valve within a pipe line or the like through which the passage of fluid is to be controlled.
- body 10 There is provided in body 10 a bore or chamber 16 which is cylindrical at its upper and lower regions as shown but has a conical intermediate portion 18 (Figure 3).
- the seat carrier 20 Received within the conical portion 18 is the seat carrier 20 which has an outer conical surface 22 complementary with the bore portion 18 and spaced therefrom when the seat carrier is properly assembled within the valve body bore 16.
- Seat carrier 20 has a through passage 24 that aligns with the passage 12 in the valve body.
- The,passage of fluid through the valve is controlled by the gate 26, the configuration of which is perhaps best shown in Figure 3 with the gate being of rectangular configuration and having a pair of opposed flat sealing surfaces 28 and 30.
- the gate is loosely received in the rectangular recess 32 that extends through the seat carrier 20 with this recess intersecting the through passage 24.
- the gate is vertically movable, as shown in Figures 1 and 2, to and from a closed position ( Figure 1) and an open position ( Figure 2). In the open position, the opening 34 in the gate is in alignment with the through passage 24 thereby permitting free flow of fluid through the valve.
- the positioning of the gate 26 is controlled by a suitable mechanism disposed within the valve bonnet 36 and any well- known mechanism for effecting this operation may be employed such as the manually operated non-rising stem mechanism generally depicted in Figure 1 and 2 and more fully illustrated and described in U.S. Patent 3,768,774 which is incorporated herein by reference.
- threaded stem 38 s loosely connected to the gate 26 by a T- slot type of connection 40. Th s permits limited relative movement between the gate and the stem.
- Stem 38 is threadedly engaged via the internal threads of the upper stem member 41 which is sealed with relation to the upper portion of bonnet 36 by suitable packing (not shown) and is operated by the hand wheel 42.
- Bonnet 36 is secured to the valve body 10 by means of the studs 44 which extend through openings in the valve bonnet and have nuts 46 threaded to their upper end for forcing the valve bonnet into position whereby its machined lower surface engages
- OMPI a complementary machine surface on the valve body at the upper end of the bore 16. Proper orientation of the bonnet with relation to the valve body is obtained by the indexing pins 48 and a seal is provided between these two members by means of the ring seal 50.
- a loading spacer which comprises two identical spacer members 52, one on each side of the gate 26. These members are secured to the seat carrier 20 by means of bolts 54 and are oriented with relation to the bonnet 36 by means of the pins 56.
- the spacers 52 are provided with inwardly projecting pins 57 which are so positioned as to engage the upper end of gate.26 when it is moved to its uppermost position.
- the purpose of these pins is to provide what is termed a unitized construction in that in assembling and disassembling the valve, the valve internals, i.e. the gate, the seat carrier, the seat loading spacer members, the ring seal and the valve bonnet, are assembled onto and disassembled from the valve body as a unit.
- the seal arrangement between the seat carrier 20 and the valve body 10 is a metallic seal, i.e.
- a seal ring 58 which, in the Figures 6, 9 and 13 embodiments, is received within an annular recess 60 of uniform depth at the outer end of the through passage 24 on each side of the seat carrier.
- the ring 58 is secured to the seat carrier so that it is inserted into and withdrawn from the valve body with the seat carrier and for this purpose ears 62 ( Figures 6 and 13) are provided. These are bent over into complementary bores or recesses 64 formed in the outer surface of the seat carrier 20 and in a manner to positively secure the ring 58 to the seat carrier.
- the ring 58 is preferably of a metallic material that is ductile and softer than the material of the seat carrier 22 and the material of the valve body 10 and when the valve internals are assembled into position by means of securing the bonnet 36 in place, the seal ring 58 is deformed somewhat (stress exceeding the elastic limit of the material) so that it conforms to any irregularities in the surfaces of the seat carrier 22 and the valve body 12 with which it mates to provide a fluid tight seal.
- the seat carrier is also deformed within its elastic limit, i.e., stressed in compression and the valve body is deformed within its elastic limit, i.e.
- the seal is energized or at least partially energized by means of the assembling of the parts into position.
- tightening down on the nuts 46 forces seat carrier 20 down into position in bore 16 via valve bonnet 36 and spacers 52 and squeezes the seal rings 58 between the surfaces of bore 19 and the bottom of recess 60 because of the tapered or conical orientation of these sufaces.
- the thickness of the ring 58 is greater than the depth of the recess or counterbore 60 so that even when the ring has been somewhat deformed into sealing engagement with the seat carrier and the valve housing and the seat carrier is in position with nuts 46 fully tightened, the complementary surfaces of the seat carrier and the valve body are in spaced relation ( Figures 9, 11, 13 and 15).
- this arrangement permits the force exerted on the seat carrier 22 by the controlled fluid when the gate is in the closed position to further energize or deform the downstream seal ring 58 in high pressure environments and thereby enhance the sealing action.
- the pressure that it seals against when in the closed position is effective to force the gate into sealing engagement with the seat carried by the seat carrier. This pressure is present throughout cavity 16 (the upstream gate seal permitting the sealed against fluid to enter this cavity) so that the downstream seal ring 58 will have developed across it whatever the differential is between the upstream and the downstream pressures.
- the valve body 10 may be AISI 4130 (a low alloy steel), the carrier may be of 17- 4 Ph (a precipitation hardening stainless steel) and the seal ring may be of "MONEL Alloy 400", substantially pure nickel or a low carbon steel plated with tin, fluoro plastic or tetra fluoro ethylene.
- FIG. 10 and 11 a modified form of seat carrier is shown.
- the recess 60 of Figures 6 and 9 is eliminated and carrier 20a has a conical surface 22a against which the seal ring 58 is pressed.
- the seal ring is held in place by bending the ears 62 into recesses 64 provided in the seat carrier.
- the top and bottom ears may be engaged by set screws 90.
- the arrangement is such that with the seat carrier 20a forced down into position in the bore 16 and the seal ring 58 energized, the seat carrier is spaced from the valve body, i.e. conical surface 22a is spaced from surface 19.
- ears 62 in addition to securing ring 58 to seat carrier 20 and 20a so that the two are assembled and disassembled to and from the valve body as a unit, tend to prevent the ring from moving relative to the seat carrier as the latter is forced down into position in bore 16.
- FIGS 12 and 13 there is disclosed a still further modified form of seat carrier.
- This embodiment is similar to that of Figure 10 but provides a cylindrical internal member which acts as a stop to prevent the seal ring from moving out of position.
- the seat carrier is identified as 20b and has the conical surface 22b similar to the conical surface in Figure 10.
- the seal ring 58 is secured to the seat in the same manner as in the previously described embodiments.
- Seat carrier 20b is provided with a counter bore 92 at the ends
- this cylindrical stop member 94 OMPI of the passage 24 and received in this counter bore is the cylindrical stop member 94.
- the outer extremity of this top member conforms with the conical surface 22b of the seat carrier and extends slightly beyond this surface but less than the thickness of the seal ring 58 when the latter is in its energized sealing position within the valve body.
- this cylindrical stop member will maintain the seal ring in position during insertion and withdrawal of the seat carrier into and from the valve body and during operation of the valve thereby preventing the seal ring 58 from being displaced and malfunctioning.
- the ring 58 has a rectangu ar configuration with relatively broad surfaces engaging the valve body and the seat carrier.
- the modified ring construction 58b as shown in Figure 8b, there is provided a slightly raised annular portion 66 directed toward the surface of the valve body when the ring is assembled into the seat carrier. This decreased area of contact with the valve body will provide a high stress area and thus a greater deformation at this location.
- the ring may be provided with a plating of soft metallic material or tetra fluoro ethylene and very satisfactory results have been achieved by coating the surface with tin.
- This plating may be provided with either the configuration of Figure 8a or Figure 8b.
- Figure 8c illustrates the ring 58c with such a coating.
- This Figure 8c shows the tin coating 68 on the surface of the ring that engages the valve body. With this arrangement, satisfactory sealing has been obtained after assembling and disassembling a valve several times with the same seal ring being used.— It will be understood that the plating material may be on both surfaces of the ring if necessary or desired. The plating may provide a lower coefficient of friction as well as enhance the sealing action.
- Figure 8d shows a still further embodiment of ring construction with this configuration having a self-energizing effect.
- the ring 58d is provided with annular raised portions
- FIG. 14 and 15 there is depicted still another embodiment of seat carrier wherein the seal ring or member is formed integral with the carrier.
- the seat carrier is identified as 20c and it has a conical surface 22c in the same manner as the previously described embodiments.
- the seal ring or member identified as 58a s formed integral with the carrier. This may be done by first machining the surface 22c on the carrier and then by means of weld beads or clad welding forming the seal ring or member 58a with th s being formed by first laying down the weld and then machining the outer surface thereof so as to conform with the conical configuration of surface 18 of the valve body 10.
- the seat carrier can be formed by precision casting in which case the surface 22c will not be machined at all but only the outer surface of the seal ring or member 58a will be machined to accurately conform to the taper of surface 18 of the valve body.
- the seal ring or member 58a will be provided with a suitabl coating such as previously described and as, for example, tin, which is softer than the material of the valve body which will deform when the seat carrier is forced into place in the valve body and thus provi es a seal between the seat carrier and the valve body.
- a metal-to-metal seal is also provided between the gate 26 and the seat carrier 20 and for this purpose, as best shown in Figure 7, seat carrier 20 is provided with recesses or counterbores 76 about the entrances of the passages 24 into the
- the gate 26 is loosely received within- the recess 32.
- the thickness 82 of the gate is smaller than the width 84 of recess 32.
- the axial dimension 86 of the seats 78 is greater than the corresponding dimension of
- the annular members 80 may, where desired, be effective to form a low pressure seal between the seat and the seat carrier prior to the build-up of sufficient pressure to give the
- valve of unitary construction which has a metal-to-metal seal between the seat carrier and the valve body as well as between the qate and the seat carrier.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Ceramic Engineering (AREA)
- Sliding Valves (AREA)
- Centrifugal Separators (AREA)
- Valve-Gear Or Valve Arrangements (AREA)
- Output Control And Ontrol Of Special Type Engine (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US45457182A | 1982-12-30 | 1982-12-30 | |
US454571 | 1982-12-30 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0144326A1 EP0144326A1 (en) | 1985-06-19 |
EP0144326A4 true EP0144326A4 (en) | 1986-05-16 |
Family
ID=23805158
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19840900169 Withdrawn EP0144326A4 (en) | 1982-12-30 | 1983-11-16 | Gate valve. |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0144326A4 (en) |
NO (1) | NO843359L (en) |
WO (1) | WO1984002758A1 (en) |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3799191A (en) * | 1972-01-31 | 1974-03-26 | Exxon Production Research Co | Compartmented underwater equipment |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2997057A (en) * | 1957-02-28 | 1961-08-22 | Gen Controls Co | Valve structure having readily removable plug and seat structures |
US3548875A (en) * | 1969-03-28 | 1970-12-22 | Speakman Co | Valve cartridge |
US3656501A (en) * | 1970-05-26 | 1972-04-18 | Fmc Corp | Valve-operator assembly with alignment and locking mechanism |
US3658087A (en) * | 1971-02-08 | 1972-04-25 | Acf Ind Inc | Valve with integral closure and seat carrier unit |
FR2158684A5 (en) * | 1971-10-28 | 1973-06-15 | Semt | |
GB1465472A (en) * | 1974-02-07 | 1977-02-23 | Shipston Eng Co Ltd | Fluid control valves |
US3989285A (en) * | 1974-12-23 | 1976-11-02 | The United States Of America As Represented By The Secretary Of The Army | Compatible vacuum seal |
-
1983
- 1983-11-16 EP EP19840900169 patent/EP0144326A4/en not_active Withdrawn
- 1983-11-16 WO PCT/US1983/001797 patent/WO1984002758A1/en not_active Application Discontinuation
-
1984
- 1984-08-23 NO NO843359A patent/NO843359L/en unknown
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3799191A (en) * | 1972-01-31 | 1974-03-26 | Exxon Production Research Co | Compartmented underwater equipment |
Also Published As
Publication number | Publication date |
---|---|
EP0144326A1 (en) | 1985-06-19 |
NO843359L (en) | 1984-08-23 |
WO1984002758A1 (en) | 1984-07-19 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 19840814 |
|
AK | Designated contracting states |
Designated state(s): FR GB |
|
A4 | Supplementary search report drawn up and despatched |
Effective date: 19860516 |
|
RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: VETCO OFFSHORE INDUSTRIES, INC. |
|
RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: VETCO GRAY INC. |
|
17Q | First examination report despatched |
Effective date: 19870717 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 19891106 |
|
RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: MAA, TSORNG, JONG |