CA2921328A1

CA2921328A1 - Wear/seat rings for gate valves and knife gate valves

Info

Publication number: CA2921328A1
Application number: CA2921328A
Authority: CA
Inventors: Darcy L. Beaumont
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-10-12
Filing date: 2016-02-18
Publication date: 2017-08-18

Abstract

A gate valve or knife gate valve consisting of housing, sliding gate and seat rings. The seat rings are coated or lined with abrasion resistant materials to protect the valve housing from abrasive slurries. The seat ring includes a locking system which prevents the ring from falling out of the valve body. The seat rings can be rotated, removed or replaced easily with dedicated custom tools. The primary use of gates and knife gate valves is for industrial transportation of abrasive slurries.

Description

Background of the Invention Gate valves and knife gate valves are commonly used to isolate piping systems.
Gate valves and knife gate valves are the preferred choice when it comes to the transport of abrasive slurries. These abrasive slurries cause damaging erosion to the internal components of gate valves and knife gate valves. Therefore, it makes sense to line the gate valves and knife gate valves with rotatable, removable and replaceable sacrificial seat rings. The wear resistant seat rings protect the valve body from erosion caused by the abrasive material being transported or moved through the piping system and valves. The inside diameter of the seat rings align with the inside diameter of the piping system.
Without the rotatable, removable and replaceable sacrificial wear resistant seat rings, the entire valve would have to be replaced or repaired frequently. The rotatable, removable and replaceable wear resistant seat ring system allows owners and operators to rotate or replace these wear resistant seat rings easily. The wear resistant seat rings are designed to work with custom tools that rotate and/or remove the wear resistant seat rings. The wear caused by erosion is most prominent in the lowermost third of the piping system and valves. This results in uneven wear in the piping system and valves. The piping system must be replaced when worn out, or, to extend their life, the piping system is disconnected and rotated to a position with relatively less erosion. As the piping system is rotated, the wear resistant seat rings must also be rotated.
The wear resistant seat ring consists of a sub-straight with a coating or liner attached to the inside diameter of the seat ring. The wear resistant seat ring can also be a single material which has anti-abrasive characteristics. The flexibility of the wear resistant seat ring enables the use of different materials and wear resistant coatings in order to accommodate a number of different applications, environments, mediums and budgets.
The inlet wear resistant seat ring can incorporate a deflection cone shape to address an issue referred to as leading edge wear. The inlet wear resistant seat ring is angled resulting in a reduced inside diameter at the gate side of the wear resistant seat ring creating a deflection cone effect. This cone shaped inlet wear resistant seat ring deflects the slurry over the leading edge of the downstream wear resistant seat ring.
This is especially critical in the lowermost third of the valve housing where the majority of the erosion takes place. Deflecting the slurry reduces damage to the leading edge of the downstream wear resistant seat ring. Leading edge wear to the downstream wear resistant seat ring can affect the sealing and shut off capabilities of the valve and result in accelerated erosion.
The primary purpose of most valves is isolation. Valves tend to leak over time, but that is especially true when valves are moving slurries. The erosive nature of slurries damages the metal to metal surfaces that seal the valve. Soft seals can also be used to seal and

2 are easily damaged by abrasive slurries. Leakage in winter months can be especially harmful as the medium bypasses the gate and freezes just downstream of the gate. This is referred to as ice damming. Ice damming causes turbulence once the gate is opened which is never desirable. As well, large chunks of frozen medium can come dislodged from the piping system resulting in a large projectile flowing down steam causing damage to the piping system. Having replaceable soft seals on the wear resistant seat rings would be highly desirable.
The wear resistant seat rings must be rotatable, removable and replaceable.
However, the wear resistant seat ring must also be locked into position to prevent the inlet wear resistant seat ring from migrating into the centre where the gate opens and closes. As well, the downstream wear resistant seat ring must be prevented from doing the same. As wear resistant seat rings come in many shapes, a variety of locking systems must be incorporated. Hex screws, notched rings, grooved rings, o rings and balls or rods with convexed ends can be used to lock the wear resistant seat rings into position.
The wear resistant seat rings can also address a common issue found with MSS-compliant gate valves and knife gate valves. These valves have both a short and long pattern (face to face dimensions) version in many sizes. This makes it very difficult to build valves to accommodate this issue and makes it difficult for operators and end users to source valves to fit within the gaps in their piping systems. The wear resistant seat rings can be extended to meet the wider face to face dimensions in the MSS-SF?-135 specifications. The wear resistant seat rings can wrap around the face of the valve on one side or both sides. Doing so would extend and widen the face to face dimensions of the valve. Therefore, one valve body can accommodate both short and long patterns by installing wear resistant seat rings of different sizes and shapes.
Existing seat ring examples include:
Knife Gate Valve Prince D
Filed: Oct 12, 1970 Completely separate bolted knife gate valve body assembly with removable wear components CA 2543718 Al James T. Leblanc, Nancy Leblanc Filed: June 13, 2013 Wear ring retainer for a gate valve Robert A Blenkush, Sidney Watterodt Filed: June 13, 2013

3 These existing designs fall short in that they do not provide easily rotation and removal of the seat rings. Existing seat rings are not designed to work with a tool that rotates and/or removes the seat rings. They lack the flexibility to easily and quickly be removed and replaced with seat rings with new or different coatings or liners. They also lack the ability to easily replace worn out seals. Lastly, they lack the flexibility to convert a short pattern valve to a long pattern valve.
Summary of the Invention The present invention relates to gate valves or a knife gate valves having seat rings.
These rings are easily rotatable, removable and replaceable. Custom dedicated tools are attached to the seat rings to rotate, remove and replace the seat rings.
The seat rings consist of a sub-straight and can have a coating or liner attached to the inside diameter of the rings. This coating or liner has abrasion resistant characteristics and properties. The wear resistant seat rings can also be a single material having anti-abrasive characteristics and properties.
The inlet wear resistant seat ring can be designed to act like a deflection cone to address leading edge wear issues. This cone shaped inlet wear resistant seat ring deflects the slurry. Deflecting the slurry reduces damage to the leading edge of the downstream seat ring.
The wear resistant seat rings can also include a seal. This seal can be easily replaced.
The seals are critical to ensure the valve does not leak. Leakage in winter can result in ice damming which is not desirable.
The wear resistant seat rings must be rotatable, removable and replaceable.
However, the wear resistant seat rings must also be locked into to position so as to prevent them from migrating into the centre where the gate opens and closes. Hex screws, notched seats, grooved seats and o rings can be used to lock the wear resistant seat rings into position.
The wear resistant seat rings can be extended to meet wider face to face dimensions found in the MSS-SP-135 knife gate specifications. The wear resistant seat rings can extend out and around the valve housing to achieve this wider face to face dimension.
One or both rings can be extended.

4 Summary of the Drawings Figure 1 shows the cut away view of the side of a gate or knife gate housing.
It consists of the valve housing, the gate, separating perimeter seal and two standard seat rings with coatings or liners.
Figure 2 shows the front view of a seat ring with mounting points for the dedicated custom tool to rotate seat rings.
Figure 3 shows the cut away view of the side of a gate or knife gate housing.
It consists of the valve housing, the gate, separating perimeter seal, one seat ring with deflection and a coating or liner and one seat ring without deflection and a coating or liner.
Figure 4 shows the cut away view of the side of a gate or knife gate housing.
It consists of the valve housing, the gate, one flanged connection, one coupling ring connection, one inlet deflection seat ring with coating or liner, one outlet seat ring with coating or liner.
Figure 5 shows an expanded cut away side view of the bottom of the valve housing with grooves. It consists of a non-separating perimeter seal, two seat rings with coatings or liners, grooves and o rings to position both seat rings.
Figure 6 shows an expanded cut away side view of the bottom of the valve housing with grooves and notches. It consists of a knife gate, two seat rings with coatings or liners, two replaceable seals, notches, grooves and o rings to position both seat rings.
One seat ring is also held in position with a removable snap ring.
Figure 7 shows an expanded cut away side view of the bottom of the valve housing with notches. It consists of a non-separating perimeter seal, two seat rings with coatings or liners and notches are positioning both seat rings.
Figure 8 shows an expanded cut away side view of the bottom of the valve housing with grooves. It consists of a separating perimeter seal, two seat rings with coatings or liners, grooves and o rings to position both seat rings.
Figure 9 shows an expanded cut away side view of the bottom of the valve housing with a grove. It consists of a separating perimeter seal, one extended wrap around seat ring with coating or liner, one non-extended seat ring with coating or liner, a groove and o ring to position the seat ring. The extended seat ring is locked into position with hex screws.
Figure 10 shows an expanded cut away side view of the bottom of the valve housing. It consists of a separating perimeter seal and two extended wrap around seat rings with coatings or liners. The extended wrap around seat rings are locked into position with hex screws.

Figure 11 shows the side view of a valve body and one seat ring. The seat ring has a hole in the outside diameter to accommodate a ball which will engage a concaved groove in the valve body. A perpendicular hole is added to the face of the seat ring to accommodate a set screw or rod. When a set screw or rod is added to this hole it forces the ball into the concaved groove on the valve body and thereby creates a locking system that prevents the ring from falling out but allows for rotation.
Figure 12 shows the side view of a valve body and one seat ring. The seat ring has a hole in the outside diameter to accommodate a rod with convexed ends. One of the convexed ends of the rod engage a concaved groove in the valve body. A perpendicular hole is added to the face of the seat ring to accommodate a set screw or rod. When a set screw or rod is added to this hole it forces the rod into the concaved groove on the valve body and thereby creates a locking system that prevents the ring from falling out but allows for rotation.
Figure 13 shows the front and side view of the custom dedicated tool that rotates the seat rings.
Detailed Description Figure 1 shows the cut away view of the side of a gate or knife gate housing (1). It consists of the valve housing (1), the gate (4), separating perimeter seal (2) and two seat rings (3) with coatings or liners (6). The perimeter seal (2) separates the two seat rings.
Figure 2 shows the front view of a seat ring (3) with mounting points (10) for the dedicated custom tool (19) to rotate seat rings (3).
Figure 3 shows the cut away view of the side of a gate or knife gate housing (1). It consists of the valve housing (1), the gate (4), separating perimeter seal (2), one seat ring with deflection (9) and a coating or liner (6), one seat ring without deflection and a coating or liner (3). The perimeter seal separates the two seat rings (3, 9).
Figure 4 shows the cut away view of the side of a gate or knife gate housing (1). It consists of the valve housing (1), the gate (4), one flanged connection (15), one coupling ring connection (13), one inlet deflection seat ring (9) with coating or liner (6), one outlet seat ring (3) with coating or liner (6). A machined notch (12) is used to position both seat rings.
Figure 5 shows an expanded cut away side view of the bottom of the valve housing (1) with groves (11). It consists of a non-separating perimeter seal (8); two seat rings (3) with coatings or liners (6) and grooves (11) and o rings (5) to position both seat rings (3).
Figure 6 shows an expanded cut away side view of the bottom of the valve housing (1) with grooves (11) and notches (12). It consists of a knife gate (20); two seat rings (3) with coatings or liners (6), two replaceable seals (17), notches (12), grooves (11) and o rings

(5) to position both seat rings (3). One seat ring (3) is also held in position with a removable snap ring (16).
Figure 7 shows an expanded cut away side view of the bottom of the valve housing (1) with notches (12). It consists of a non-separating perimeter seal (8); two seat rings (3) with coatings or liners (6) and notches (12) are positioning both seat rings (3).
Figure 8 shows an expanded cut away side view of the bottom of the valve housing (1) with grooves (11). It consists of a separating perimeter seal (2); two seat rings (3) with coatings or liners (6), grooves (11) and o rings (5) to position both seat rings (3).
Figure 9 shows an expanded cut away side view of the bottom of the valve housing (1) with a groove (11). It consists of a separating perimeter seal (2), one extended wrap around seat ring (7) with coating or liner (6), one non-extended seat ring (3) with coating or liner (6), a groove (11) and o ring (5) to position the seat ring (3). The extended seat ring (7) is locked into position with hex screws (18).
Figure 10 shows an expanded cut away side view of the bottom of the valve housing (1). It consists of a separating perimeter seal (2) and two extended wrap around seat rings (7) with coatings or liners (6). The extended wrap around seat rings (7) are locked into position with hex screws (18).
Figure 11 shows the side view of a valve body (1) and one seat ring (3). The seat ring (3) has a hole in the outside diameter to accommodate a ball (21) which will engage a concaved groove in the valve body (1). A perpendicular hole is added to the face of the seat ring to accommodate a set screw or rod (23). When a set screw or rod (23) is added to this hole it forces the ball (21) into the concaved groove on the valve body and thereby creates a locking system that prevents the ring (3) from falling out but allows for rotation.
Figure 12 shows the side view of a valve body (1) and one seat ring (3). The seat ring (3) has a hole in the outside diameter to accommodate a rod (22) with convexed ends. One of the convexed ends of the rod 22 engage a concaved groove in the valve body 1.
A
perpendicular hole is added to the face of the seat ring to accommodate a set screw or rod 23. When a set screw or rod 23 is added to this hole it forces the rod 22 into the concaved groove on the valve body 1 and thereby creates a locking system that prevents the ring 3 from falling out but allows for rotation.
Figure 13 shows the front and side view of the custom dedicated tool (19) with mounting points 10 for rotation of seat rings (3, 9).

Claims

Claims "The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows".
A gate valve or knife gate valve consisting of a housing, parallel sliding gate or knife gate and parallel seat rings.

1. A seat ring consisting of an upstream and downstream ring with a parallel gate or knife gate opening and closing between them.

2. A seat ring consisting of an inside diameter that matches the inside diameter of the piping system it is attached to.

3. The seat ring provides a seal between the seat and gate when upstream or downstream pressure is applied to a closed gate or knife gate.

4. A seat ring that guides and supports the gate or knife gate as it opens and closes.

5. A seat ring consisting of a tight tolerance fit between the outside diameter of the seat ring and valve housing opening.

6. A seat ring consisting of dimensions to ensure that the gate is not pinched when the valve housing is compressed between the downstream and up-stream piping system.

7. A seat ring that can be rotated removed or replaced by use of dedicated custom tools.

8. A seat ring consisting of mounting points to accommodate dedicated custom tools for rotating, removal and replacement of the seat ring or replaceable soft seal.

9. A seat ring consisting of multiple different materials, shapes, thicknesses, widths, inside and outside dimensions.

10.A seat ring consisting of a wear resistant coating or liner attached to its inside diameter to protect the valve housing and internal components of a gate or knife gate valve from erosion and damage.

11.A seat ring consisting of multiple different wear resistant coatings or liners.

12.A seat ring consisting of a single material with abrasion resistant characteristics and properties.

13.A seat ring consisting of a full port or reduced port.

14.An upstream (inlet) seat ring consisting of a cone shape to deflect abrasive slurries over the leading edge of the downstream seat ring.

15.A seat ring consisting of a soft seal that is energized when compressed to provide a tight shut off when the gate or knife gate is closed.

16.A seat ring consisting of a soft seal that is replaceable.

17. A seat ring consisting of multiple different locking mechanisms to position the seat ring on either side of the gate or knife gate allowing the gate or knife gate to open and close freely.

18.A seat ring consisting of multiple different locking mechanisms which include hex screws, notched seat, grooved seat and o rings.

19.A seat ring consisting of multiple different locking mechanisms which still allow the seat to be rotated removed or replaced.

20.A seat ring consisting of a ball positioned in a hole on the outside diameter of the seat ring which is recessed into the hole in the seat ring and is flush with the outside diameter of the seat ring until a set screw or rod is added to a perpendicular hole which forces the ball to protrude from the hole on the outside diameter of the seat ring and engage a concaved groove in the valve body creating a locking system which still allows the seat ring to be rotated.

21.A seat ring consisting of a rod with convexed ends positioned in a hole on the outside diameter of the seat ring which is recessed into the hole in the seat ring and is flush with the outside diameter of the seat ring until a set screw or rod is added to a perpendicular hole which forces the rod to protrude from the hole on the outside diameter of the seat ring and engage a concaved groove in the valve body creating a locking system which still allows the seat ring to be rotated.

22.A seat ring consisting of dimensions that meet short pattern face to face dimensions found in the MSS-SP-135 specifications.

23.A seat ring consisting of dimensions that meet long pattern face to face dimensions found in the MSS-SP-135 specifications.

24.A seat ring consisting of dimensions that extend and wrap around the face of the valve body to make a short pattern valve (face to face dimensions) into a long pattern valve (face to face dimensions) found in the MSS-SP-135 specifications.

25.A seat ring consisting of dimensions that can be integrated into MSS-SP-81 compliant gate valves and knife gate valves.

26.A seat ring consisting of dimensions that extend and wrap around the face of the valve body to make a short pattern valve (face to face dimensions) into a long pattern valve (face to face dimensions) for MSS-SP-81 gate valves and knife gate valves.