CA1086706A - Knife gate valve - Google Patents
Knife gate valveInfo
- Publication number
- CA1086706A CA1086706A CA319,437A CA319437A CA1086706A CA 1086706 A CA1086706 A CA 1086706A CA 319437 A CA319437 A CA 319437A CA 1086706 A CA1086706 A CA 1086706A
- Authority
- CA
- Canada
- Prior art keywords
- flange
- slot
- space
- flow passage
- ring
- 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
Links
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
- F16K3/0281—Guillotine or blade-type valves, e.g. no passage through the valve member
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Sliding Valves (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A packingless knife gate valve is disclosed having a flow passage of substantially the same diameter therethrough. The valve comprises a pair of valve body housings each having a connector flange with a flange surface perpendicular to the flow passage, the flange surface on one housing facing the flange surface on the other housing. A slot is provided in each flange surface extending around the flow passage with the slot in one flange surface aligned with the slot in the other flange surface, a space between the flange surfaces having a guiding means on each side, means for connecting the two flanges together with the space between, a seal ring in each slot with a sealing surface of one ring touching a sealing surface of the other ring in the space between the flange surfaces, and a knife gate having a sharp edge disposed between the sealing surfaces of the seal rings adapted to move backwards and forwards in the space within the guiding means.
A packingless knife gate valve is disclosed having a flow passage of substantially the same diameter therethrough. The valve comprises a pair of valve body housings each having a connector flange with a flange surface perpendicular to the flow passage, the flange surface on one housing facing the flange surface on the other housing. A slot is provided in each flange surface extending around the flow passage with the slot in one flange surface aligned with the slot in the other flange surface, a space between the flange surfaces having a guiding means on each side, means for connecting the two flanges together with the space between, a seal ring in each slot with a sealing surface of one ring touching a sealing surface of the other ring in the space between the flange surfaces, and a knife gate having a sharp edge disposed between the sealing surfaces of the seal rings adapted to move backwards and forwards in the space within the guiding means.
Description
6~
Th~ present invention rclat~s to gate valves suitabl~
.or controlling the flow of abrasive slurries such as tailings from mining operations and the like.~ More particularly the in-vention relates to a knife gate valve having no gate packing box or stem packing box.
A knife gate valve having a thin bladed knife gate with a sharp edge which is forced between two seals made o~ resilient material is known. Examples of these types of valves are shown in Canadian Patent 598,397 and 614,768 to Williams and U.S. Patent -~
3,333,816 to Williams et al. All of the valves shown in these patents, however, include a gate or stem packing box to prevent leakage from the valve. These packing boxes cause the valve to become bulky and complex.
Clarkson in Canadian Patent 1,017,315 discloses a pack-lngless knife gate valve, but which has a special insert piece hav-ing a larger internal diameter than the normal flow passage way and a special liner to fit therein.
The present invention provides a packingless gate valve which has a pair of valve body housings which may have standard l`
pipe flange fittings, Victaulic (trade mark) pipe fittings or other types of fittings for standard pipe connections. The pair of valve bodies together need not be so wide as the valve shown in the Clarkson patent. Furthermore, the end connections of both valve bodies are standard pipe connections unlike the valve shown in the Clnrkson patent.
Packingless valves do from time to time leak and the present valve has a space between the two flange body housings mnintained by spacer strips on each side of the flowpassa~e and any leakage that does occur is allowed to drain from this space and does not cause a build up of particles which could prevent operation of the valve. The valve body housings each have a flange surface which is substantially perpendicular to the flow passage, the flange ,, ,~ . .
~0~ 1D6 ~surfaces on the pair of housings oppose each other. Each ~lange surface has a slot and the slo~s in the opposing ~lang~ sur~ac~s are aligned and extend around the ~low passage with a seal ring fitting in ~ach slot. lrhe seal ring has a sealing surface which mates with the sealing surface of the other seal ring and a knife blade is forced betwaen these two sealing surfaces which part to allow the knife blade to close the flow passage in the valve.
The present invention provides a packingless gate valve comprising a pair of valve body housings, each housing having a flow passage of substantially the same diameter therethrough, each housing having a connector flange with a flange surface perpendic-ular to the flow passage, the ~lange surface on one housing facing the flange surface on the other housing, a slot in each flange surface e~tending around the flow passage, the slot in one flange surface aligned with the slot in the other flange surface, a space between the flange surfaces having a guiding means on each side, means for connecting the two flanges together with the space in between, a seal ring in each slot with a sealing surface of one ring touching a sealing surface of the other ring in the space between the flange surfaces and a knife gate having a sharp edge disposed between the sealing surfaces of the seal rings adapted ~o move backwards and forwards in the space within the guiding means.
In other embodiments of the present invention the gate vnlve has seal rings which each have a circular backing ring with rasillent material attached thereto, the backing riDg being re-placeable wlthin the slot. In another embodiment, the sealing surface of each seal ring is radiused and in another embodiment the sealing surface of each seal ring has chamfered edges. In a still further embodiment, spacer strips are located at each side of the flow passage outboard of the slot in the space between the flange surfaces, the spacers forming the guiding means for the .
Th~ present invention rclat~s to gate valves suitabl~
.or controlling the flow of abrasive slurries such as tailings from mining operations and the like.~ More particularly the in-vention relates to a knife gate valve having no gate packing box or stem packing box.
A knife gate valve having a thin bladed knife gate with a sharp edge which is forced between two seals made o~ resilient material is known. Examples of these types of valves are shown in Canadian Patent 598,397 and 614,768 to Williams and U.S. Patent -~
3,333,816 to Williams et al. All of the valves shown in these patents, however, include a gate or stem packing box to prevent leakage from the valve. These packing boxes cause the valve to become bulky and complex.
Clarkson in Canadian Patent 1,017,315 discloses a pack-lngless knife gate valve, but which has a special insert piece hav-ing a larger internal diameter than the normal flow passage way and a special liner to fit therein.
The present invention provides a packingless gate valve which has a pair of valve body housings which may have standard l`
pipe flange fittings, Victaulic (trade mark) pipe fittings or other types of fittings for standard pipe connections. The pair of valve bodies together need not be so wide as the valve shown in the Clarkson patent. Furthermore, the end connections of both valve bodies are standard pipe connections unlike the valve shown in the Clnrkson patent.
Packingless valves do from time to time leak and the present valve has a space between the two flange body housings mnintained by spacer strips on each side of the flowpassa~e and any leakage that does occur is allowed to drain from this space and does not cause a build up of particles which could prevent operation of the valve. The valve body housings each have a flange surface which is substantially perpendicular to the flow passage, the flange ,, ,~ . .
~0~ 1D6 ~surfaces on the pair of housings oppose each other. Each ~lange surface has a slot and the slo~s in the opposing ~lang~ sur~ac~s are aligned and extend around the ~low passage with a seal ring fitting in ~ach slot. lrhe seal ring has a sealing surface which mates with the sealing surface of the other seal ring and a knife blade is forced betwaen these two sealing surfaces which part to allow the knife blade to close the flow passage in the valve.
The present invention provides a packingless gate valve comprising a pair of valve body housings, each housing having a flow passage of substantially the same diameter therethrough, each housing having a connector flange with a flange surface perpendic-ular to the flow passage, the ~lange surface on one housing facing the flange surface on the other housing, a slot in each flange surface e~tending around the flow passage, the slot in one flange surface aligned with the slot in the other flange surface, a space between the flange surfaces having a guiding means on each side, means for connecting the two flanges together with the space in between, a seal ring in each slot with a sealing surface of one ring touching a sealing surface of the other ring in the space between the flange surfaces and a knife gate having a sharp edge disposed between the sealing surfaces of the seal rings adapted ~o move backwards and forwards in the space within the guiding means.
In other embodiments of the present invention the gate vnlve has seal rings which each have a circular backing ring with rasillent material attached thereto, the backing riDg being re-placeable wlthin the slot. In another embodiment, the sealing surface of each seal ring is radiused and in another embodiment the sealing surface of each seal ring has chamfered edges. In a still further embodiment, spacer strips are located at each side of the flow passage outboard of the slot in the space between the flange surfaces, the spacers forming the guiding means for the .
- 2 -.,~ .
- "i ' "' i7~16 knife gate.
In drawings which illustrate embodiments oi th~ inv~ntion Fig. 1 is a cross sectional elevation through one embod-iment of the knife gate valv~ of the present invention.
Fig. 2 iS a cross ~ectional view taken at line 2-2 of Fig. 1. ;
Fig. 3 is an end view of one embodiment of a valve according to the present invention showing the operator mechanism.
Referring now to th~ drawings, Fig. 1 and 2 show one embodiment of a knife gate valve according to the present invention wherein a first valve body housing 10 is connected to second valve body housing 11~ Both valve body housings 10 and 11 are substan-tially the same, they have a standard pipe flange 12 at one end with bolt holes 13 for connection to a pipe flange ~or a conduit or other connector. It will be appreciated that the standard pipe ~lange does not necessarily form part of this valve, the end con-nection may be a Victaulic type pips connection or olle end could be one type of end connection and the other end a di~ferent typs o~
end connection. The inside surfaces o~ the valve body housings 10 and 11 have connector ~langes 14 which both have flange surfaces 15 ~acing each other and substantially perpendicular to a ~low passage 16 in th~ valve body housings 10 and 11. The flow passage 16 in both body housings is sub~tant1ally the same cliameter. Each connector ~lange 14 is substantially rectangular in shape, and has a row o~ holes 17 in each flange 14 at opposite sides of the flow passage 16, and two spacer strlps 18 having holes therein to match the holes in the ~langes 14 are placed one on each side o~ ths flow passage 16 between the two ~langes 14 so that when the two flanges -~
14 are bolted together by bolts 19 through bolt holes 17 the spacer strips 18 provide a space 20 between t~e two flange surfa¢es 15~ Thus the spacer strips l8 provide guiding means for the knife gate valve. -~
A slot 21 having a rectangular cross se~tion is located in each ~lange surface lS around the flow passage 16 but within the area o~
- "i ' "' i7~16 knife gate.
In drawings which illustrate embodiments oi th~ inv~ntion Fig. 1 is a cross sectional elevation through one embod-iment of the knife gate valv~ of the present invention.
Fig. 2 iS a cross ~ectional view taken at line 2-2 of Fig. 1. ;
Fig. 3 is an end view of one embodiment of a valve according to the present invention showing the operator mechanism.
Referring now to th~ drawings, Fig. 1 and 2 show one embodiment of a knife gate valve according to the present invention wherein a first valve body housing 10 is connected to second valve body housing 11~ Both valve body housings 10 and 11 are substan-tially the same, they have a standard pipe flange 12 at one end with bolt holes 13 for connection to a pipe flange ~or a conduit or other connector. It will be appreciated that the standard pipe ~lange does not necessarily form part of this valve, the end con-nection may be a Victaulic type pips connection or olle end could be one type of end connection and the other end a di~ferent typs o~
end connection. The inside surfaces o~ the valve body housings 10 and 11 have connector ~langes 14 which both have flange surfaces 15 ~acing each other and substantially perpendicular to a ~low passage 16 in th~ valve body housings 10 and 11. The flow passage 16 in both body housings is sub~tant1ally the same cliameter. Each connector ~lange 14 is substantially rectangular in shape, and has a row o~ holes 17 in each flange 14 at opposite sides of the flow passage 16, and two spacer strlps 18 having holes therein to match the holes in the ~langes 14 are placed one on each side o~ ths flow passage 16 between the two ~langes 14 so that when the two flanges -~
14 are bolted together by bolts 19 through bolt holes 17 the spacer strips 18 provide a space 20 between t~e two flange surfa¢es 15~ Thus the spacer strips l8 provide guiding means for the knife gate valve. -~
A slot 21 having a rectangular cross se~tion is located in each ~lange surface lS around the flow passage 16 but within the area o~
- 3 -, ~ , . . . . .
6~7~
~he flang~ sur-~ac~ no-t cover~d by the spacor strip lB. The slot 21 axtends in a circle around the flow passage, and is aligned with the slot 21 in the opposite or adjacent valve body housing.
A seal ring 22 is located in each slot 21, the seal ring having a sealing sur~ace 23 so that the two seal rings 22 mate and seal at their sealing surfaces 23 in the space 20 between the ~lange surfaces 15 to prev~nt the liquid in tha valve escaping.
As shown in the drawings, the seal ring 22 has a circular metal bac~ing ring 24 with a resilient material attached thereto.
The resilient material forms the sealing surface 23 of the seal ring 21, the metal backing ring, preferably steel, acts as a rigid ~
support to retain the seal ring 22 within the slot 21. A rectan- -gular knii'e blade 25 having a tapered sharp edge 26 is supported ~rom a valve stem 27 and passes between the sealing surfaces 23 of the seal rings 22. The knife blade 25 passes between the spacer strips 18 on each side of the flanges 14 which act as guidas. As the knife blade 25 slowly moves downwards in the gap 20, the seal-ing surfaces 23 on the seal rings 22 are parted, but seal to bo-th sides of the knife blade 25. The knife blade may be located at any position within the flow passage 16 and in this manner9 the valve can be partially closed. When the knife blade 25 passes to ~he bottom of the valve body housing, the valve is closed complete-ly. ' The sealing surface 23 of each seal ring 22 may be sub-stantially flat as shown alternatively it may be radiused or have ch~mfered edges to provide easier parting when the sharp edge 26 o~ the Icnife gate 25 passes between the seal rings 22. In a pre-ferred embodiment the seal ring is formed from a Linatex (reg-istered trade mark) rubber material adhesively aittached to a steel ring. The seal ring 22 may be formed of a flexible material having a hardness of 35 to 40 Shore A Durometer. The backing ring may be a harder rubber or plastic material sufficient to support the ~01~16~
flexible portion which has th~ sealing sur~ace 23 thereon when the knife gate 25 is forced between the sealing sur~aces. In one embodiment the knife gate is between 1/8 and 1/~ inch thick.
Fig. 3 shows an operating mechanism for the knife gate valve illustrated in Fig. 1 and 2 wherein the stem 27 connected to the knife blade 25 is a threaded spindle and extends upwards through a housing 30 which has a spindle nut 31 connected to a hand wheel 32. The housing 30 is mounted on a frame 33 with legs 3~ supported from the top side bolts 19 on each side of the valve body. Rotating the hand wheel 32 causes the spindle nut to rotate and the stem 27 rise upwards or downwards depending on the direc-tions of rotation, and thus move the knife blade 25. In a pre-ferred embodiment an indicator may be provided showing the exact location of the knife blade 25 within the flow passage of the valve.
In another embodiment the spacer strips 18 between the two ~langes 1~ are omitted, and each flange has a shoulder and raised surface which rest adjacent to each other thus leaving the space 20 between the flangas. The space 20 is of sufficient width to allow passage of the knife gate and the shoulders on the flanges at each side provide guides for the kni~e blade. ;
It will be understood by those skilled in the art that various changes may be made to this particular valve, for example an abrasive lining may be added in both halves of the valve body housings to avoid wear of the metal in the flow passage. The ~eal ring 22 may be replaced by merely removing the bolts 19 between the two connector flanges 1~, parting the flanges, removing -~he old seal rings 22 and inserting new seal rings into the slots 21. Other changes may be made to the knife gate valve of the present invention without departing from the scope of the present invention which is only limited by the claims.
6~7~
~he flang~ sur-~ac~ no-t cover~d by the spacor strip lB. The slot 21 axtends in a circle around the flow passage, and is aligned with the slot 21 in the opposite or adjacent valve body housing.
A seal ring 22 is located in each slot 21, the seal ring having a sealing sur~ace 23 so that the two seal rings 22 mate and seal at their sealing surfaces 23 in the space 20 between the ~lange surfaces 15 to prev~nt the liquid in tha valve escaping.
As shown in the drawings, the seal ring 22 has a circular metal bac~ing ring 24 with a resilient material attached thereto.
The resilient material forms the sealing surface 23 of the seal ring 21, the metal backing ring, preferably steel, acts as a rigid ~
support to retain the seal ring 22 within the slot 21. A rectan- -gular knii'e blade 25 having a tapered sharp edge 26 is supported ~rom a valve stem 27 and passes between the sealing surfaces 23 of the seal rings 22. The knife blade 25 passes between the spacer strips 18 on each side of the flanges 14 which act as guidas. As the knife blade 25 slowly moves downwards in the gap 20, the seal-ing surfaces 23 on the seal rings 22 are parted, but seal to bo-th sides of the knife blade 25. The knife blade may be located at any position within the flow passage 16 and in this manner9 the valve can be partially closed. When the knife blade 25 passes to ~he bottom of the valve body housing, the valve is closed complete-ly. ' The sealing surface 23 of each seal ring 22 may be sub-stantially flat as shown alternatively it may be radiused or have ch~mfered edges to provide easier parting when the sharp edge 26 o~ the Icnife gate 25 passes between the seal rings 22. In a pre-ferred embodiment the seal ring is formed from a Linatex (reg-istered trade mark) rubber material adhesively aittached to a steel ring. The seal ring 22 may be formed of a flexible material having a hardness of 35 to 40 Shore A Durometer. The backing ring may be a harder rubber or plastic material sufficient to support the ~01~16~
flexible portion which has th~ sealing sur~ace 23 thereon when the knife gate 25 is forced between the sealing sur~aces. In one embodiment the knife gate is between 1/8 and 1/~ inch thick.
Fig. 3 shows an operating mechanism for the knife gate valve illustrated in Fig. 1 and 2 wherein the stem 27 connected to the knife blade 25 is a threaded spindle and extends upwards through a housing 30 which has a spindle nut 31 connected to a hand wheel 32. The housing 30 is mounted on a frame 33 with legs 3~ supported from the top side bolts 19 on each side of the valve body. Rotating the hand wheel 32 causes the spindle nut to rotate and the stem 27 rise upwards or downwards depending on the direc-tions of rotation, and thus move the knife blade 25. In a pre-ferred embodiment an indicator may be provided showing the exact location of the knife blade 25 within the flow passage of the valve.
In another embodiment the spacer strips 18 between the two ~langes 1~ are omitted, and each flange has a shoulder and raised surface which rest adjacent to each other thus leaving the space 20 between the flangas. The space 20 is of sufficient width to allow passage of the knife gate and the shoulders on the flanges at each side provide guides for the kni~e blade. ;
It will be understood by those skilled in the art that various changes may be made to this particular valve, for example an abrasive lining may be added in both halves of the valve body housings to avoid wear of the metal in the flow passage. The ~eal ring 22 may be replaced by merely removing the bolts 19 between the two connector flanges 1~, parting the flanges, removing -~he old seal rings 22 and inserting new seal rings into the slots 21. Other changes may be made to the knife gate valve of the present invention without departing from the scope of the present invention which is only limited by the claims.
Claims (5)
1. A packingless gate valve comprising a pair of valve body housings, each housing having a flow passage of substantially the same diameter therethrough, each housing having a connector flange with a flange surface perpendicular to the flow passage, the flange surface on one housing facing the flange surface on the other housing, a slot in each flange surface extending around the flow passage, the slot in one flange surface aligned with the slot in the other flange surface, a space between the flange surfaces having a guiding means on each side, means for connect-ing the two flanges together with the space between, a seal ring in each slot with a sealing surface of one ring touching a sealing surface of the other ring in the space between the flange surfaces, and a knife gate having a sharp edge disposed between the sealing surfaces of the seal rings adapted to move backwards and forwards in the space within the guiding means.
2. The gate valve according to claim 1 wherein the seal ring has a circular backing ring with resilient material attached thereto, the backing ring being replaceable within the slot.
3. The gate valve according to claim 2 wherein the sealing surface of the seal ring is radiused.
4. The gate valve according to claim 2 wherein the sealing surface of the seal ring has chamfered edges.
5. The gate valve according to claim 1 or claim 2 wherein spacer strips are located one at each side of the flow passage outboard of the slot in the space between the flange surfaces, the spacers forming the guiding means for the knife gate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA319,437A CA1086706A (en) | 1979-01-10 | 1979-01-10 | Knife gate valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA319,437A CA1086706A (en) | 1979-01-10 | 1979-01-10 | Knife gate valve |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1086706A true CA1086706A (en) | 1980-09-30 |
Family
ID=4113288
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA319,437A Expired CA1086706A (en) | 1979-01-10 | 1979-01-10 | Knife gate valve |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1086706A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4765361A (en) * | 1987-06-29 | 1988-08-23 | Clifford Walter A | Ported gate valve |
| EP2990546A3 (en) * | 2014-08-29 | 2016-06-22 | PKZ v.o.f. | Method for replacing a fluid conduit, and closure coupler |
| NL2013388B1 (en) * | 2014-08-29 | 2016-09-26 | Pkz V O F | Method for replacing a fluid line and shut-off coupling. |
| US11300213B1 (en) | 2021-02-19 | 2022-04-12 | Emerson Automation Solutions Final Control US LP | Floating yoke connection |
| US11499644B2 (en) | 2020-08-25 | 2022-11-15 | Emerson Automation Solutions Final Control US LP | Sealing assembly for a knife gate valve |
-
1979
- 1979-01-10 CA CA319,437A patent/CA1086706A/en not_active Expired
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4765361A (en) * | 1987-06-29 | 1988-08-23 | Clifford Walter A | Ported gate valve |
| EP2990546A3 (en) * | 2014-08-29 | 2016-06-22 | PKZ v.o.f. | Method for replacing a fluid conduit, and closure coupler |
| NL2013388B1 (en) * | 2014-08-29 | 2016-09-26 | Pkz V O F | Method for replacing a fluid line and shut-off coupling. |
| US11499644B2 (en) | 2020-08-25 | 2022-11-15 | Emerson Automation Solutions Final Control US LP | Sealing assembly for a knife gate valve |
| US11300213B1 (en) | 2021-02-19 | 2022-04-12 | Emerson Automation Solutions Final Control US LP | Floating yoke connection |
| US11603938B2 (en) | 2021-02-19 | 2023-03-14 | Emerson Automation Solutions Final Control US LP | Floating yoke connection |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |