Systems and methods for gate valves

A gate valve system includes a body including an upstream end, a downstream end, and a flow path extending through the upstream end and the downstream end. The gate valve system includes a gate assembly extending within the body, the gate assembly including a gate a stem secured to the gate and configured to place the expandable gate in a first position in which a flow of fluid is permitted between the upstream end and the downstream end and a second position in which the flow of fluid is prevented. The gate valve system also includes a lubrication port in an exterior of the body, the lubrication port being in fluid communication with an interior of the body and including a lubrication guiding insert configured to guide a supply of lubricating fluid to a location inside the body and between the upstream end and the downstream end.

TECHNICAL FIELD

Aspects of the present disclosure relate generally to valves and valve systems useful, for example, in oil and gas applications. In particular, aspects of the present disclosure relate to methods and systems for expanding gate valve assemblies.

BACKGROUND

Valve devices, such as gate valve assemblies, are useful for fluid handling in, for example, the oil and gas, power, chemical, water works, waste water, and manufacturing industries. Gate valve systems in particular are useful to selectively permit or block the flow of large volumes of fluid. Gate valves are robust systems that operate in harsh environments and under severe conditions. In order to perform in these environments, valve systems include components that are resistant to debris, corrosion, and wear. In order to ensure continued operation of the valve, components are regularly inspected and maintained. However, even when inspections and maintenance are performed regularly, wear occurs on moving parts that are inaccessible while the valve is in service. In addition to wear, corrosion can occur within the valve, often affecting locations that are inaccessible or difficult to access without removing the valve device from adjacent fluid handling components. Removing the valve from a line is a time consuming process.

Since it is desirable to infrequently remove the valve for maintenance or repair, components that are difficult to access may experience wear and corrosion at an increased rate compared to more readily-accessible components of the valve system. Wear and damage may occur even more quickly when lubrication becomes depleted. However, existing valve devices do not include adequate mechanisms for lubricating components of the valve that are difficult to access when the valve is connected to upstream and downstream components.

Additionally, under some circumstances, leaks can develop in one or more areas of the valve, such as a valve seat. Leaks, while rare, are critical conditions requiring immediate attention that disrupt operations. Traditional valve systems lack mechanisms for quickly halting a leak, potentially resulting in hazardous conditions.

SUMMARY

According to certain embodiments, systems and methods are disclosed for a gate valve for fluid handling.

In one aspect, a gate valve system may include a body having an upstream end, a downstream end, and a flow path extending through the upstream end and the downstream end. The gate valve system may include a gate assembly extending within the body, the gate assembly including a gate a stem secured to the gate and configured to place the expandable gate in a first position in which a flow of fluid is permitted between the upstream end and the downstream end and a second position in which the flow of fluid is prevented. The gate valve system may also include a lubrication port in an exterior of the body, the lubrication port being in fluid communication with an interior of the body and including a lubrication guiding insert configured to guide a supply of lubricating fluid to a location inside the body and between the upstream end and the downstream end.

In another aspect, a gate valve system may include a body having an upstream end forming an upstream opening a downstream end forming a downstream opening and an expandable gate moveable between an open position and a closed position. The gate valve system may include a seat ring positioned to contact the expandable gate when the expandable gate is in the closed position, the seat ring including a radially-extending passage and a sealant port extending within the body, the sealant port being in fluid communication with the radially-extending hole in the seat ring.

In yet another aspect, a method of assembling a gate valve system may include forming a body including an upstream end, a downstream end, and a flow path extending through the upstream end and the downstream end and placing an expandable gate valve assembly within the body, the expandable gate valve assembly including a gate within the body and a stem secured to the gate, the stem being configured to actuate the expandable gate between a first position in which a flow of fluid is permitted between the upstream end and the downstream end and a second position in which the flow of fluid is prevented. The method may also include forming a lubrication port in an exterior of the body, the lubrication port being in fluid communication with an interior of the body and including a lubrication guiding insert configured to guide a supply of fluid to a location between the upstream end and the downstream end.

In one aspect, an expanding gate valve assembly may include a body having an upstream end and a downstream end, a bonnet secured to the body, a gate assembly extending within the body and the bonnet, the gate assembly including a stem and an expandable gate, and a lubrication port formed in the body, the lubrication port providing access to the gate, wherein the lubrication port is located between the upstream end and the downstream end.

In another aspect, a method of servicing a gate valve assembly may include coupling a lubricant-introducing member having an internal fluid passage to a port of a body of the gate valve assembly, connecting an injection fitting to a recess formed in the lubricant-introducing member, and providing a supply of lubricant to a moving component of the gate valve assembly by injecting the lubricant through the injection fitting and through the lubricant-introducing member.

In another aspect, an expanding gate valve assembly may include a body having an upstream end and a downstream end, a bonnet secured to the body, and a gate assembly extending within the body and the bonnet, the gate assembly including a stem and an expandable gate. The expanding gate valve assembly may also include a seal ring provided in the body and configured to form a seal with the gate and a port formed in the seal ring configured to receive sealant, the port forming a path for sealant toward at least one of the body or the gate.

In yet another aspect, a method of servicing a gate valve assembly may include closing the gate valve assembly by causing an expanding gate to contact a seat ring and introducing a sealant into a port provided on a seat to seal a leak in the gate valve assembly, wherein the sealant is introduced by a port provided on an inner circumferential surface of the seat ring when the gate valve assembly is under pressure.

DETAILED DESCRIPTION

FIG.1is a front view of an expanding gate valve assembly or system10according to aspects of the present disclosure. Gate valve system10may include a body12, a bonnet14, a stem16, and a gate assembly20(FIG.3) secured to stem16. Body12may extend from an upstream end110to a downstream end120(FIG.2), and include an upper end to which bonnet14is secured. Transverse ends140and150may extend between upstream and downstream ends110and120. Stem16may extend through bonnet14and the upper end of body12. Stem16may be secured at a center of valve system10, between upstream and downstream ends110and120, and between transverse ends140and150. Annular flanges or ports130, formed at upstream and downstream ends110and120, may be sized and shaped for connection to upstream and downstream pipeline components, and may include a series of bolt holes to allow ports130to facilitate leak-free connections to these components. A valve23, such as a ball valve, may allow an operator to withdraw a sample of fluid from valve system10during inspection or maintenance.

Body12and bonnet14may be formed of any suitable material. For example, body12and bonnet14may be formed of corrosion-resistant materials. In particular body12and bonnet14may be formed of a metal material, such as stainless steel (e.g., 17-4 stainless steel), carbon steel, etc.

Gate valve system10may include one or more service or lubrication ports30. Lubrication ports30may provide access to an interior of body12for a supply of lubricating fluid. Each lubrication port30may be positioned so as to protrude from body12at transverse end140or transverse end150. Similarly, transverse end150may include two or more lubrication ports30. Each lubrication port30may be in fluid communication with an interior of body12. For example, lubrication port30may be configured to guide a lubricating fluid, such as grease, to a location between upstream end110and downstream end120, as described below.

With reference toFIG.2, bonnet14may be secured to body12such that bonnet14surrounds stem16. Bonnet14may be secured to body12in any suitable manner. For example, bonnet14may receive a plurality of fasteners80, such as bolts, and a respective plurality of fixing members82, such as nuts (FIG.1). An upper plate34may form a flange positioned above bonnet14so as to extend proximally away from body12toward a proximal end of stem16. A packing injection fitting28may be provided on bonnet14to facilitate insertion of packing material for sealing stem16. Upper surface34and stem16may be provided at a central portion of valve system10between upstream end110and downstream end120.

FIG.3is a cross-sectional view along line III-Ill ofFIG.1. As shown inFIG.3, a gate assembly20may be moveably secured within a hollow interior of body12. Gate assembly20may include stem16, which includes a proximal end protruding through both bonnet14and upper plate34, and a distal end fixed to an expandable gate22. The proximal end of stem16, which corresponds to the upper end of stem16as shown inFIG.3, may be operably connected to an actuator18to operate gate assembly20. A packing assembly32may be provided within bonnet14adjacent to stem16. Packing assembly32may be configured to seal stem16and secure against leakage at an upper surface of bonnet14. Bonnet14make be secured to body12via an O-ring100and a gasket102.

Actuator18may include a handwheel that facilitates manual actuation of gate assembly20. For example, actuator18may include an internally-threaded handwheel that, when manually operated, raises and lowers gate assembly20to move gate assembly20between an open position and a closed position, respectively. In some configurations, actuator18may instead include a pneumatic control device configured to selectively position gate assembly20in the open position and the closed position. One or more controllers (not shown) may monitor states of a pipeline, such as fluid pressure upstream and/or downstream of gate valve system10. In response to detected states (e.g., a drop or increase in pressure below or above respective predetermined threshold values), the controller may actuate stem16and gate assembly20so as to block or permit flow of fluid between upstream end110and downstream end120, as desired, by introducing or removing air to the pneumatic control device. In such a configuration, valve assembly20be closed in response to the detection of a loss of upstream or downstream pressure, for example.

Valve seats or seat rings90may be secured within body12so as to face and abut upstream and downstream ends of gate assembly20. Seat rings90may be removably secured to body12, e.g., by threading or by press-fitting. Alternatively, seat rings90may be permanently secured to body12by welding.

With continued reference toFIG.3, stem16may extend within body12such that the distal end of stem16is fixed to gate22. A gate segment36of gate assembly20may be slidably secured to gate22. Gate segment36and gate22may have any suitable shape. For example, segment36and gate22may be disc-shaped, wedge shaped, etc. In some configurations, gate segment36may be configured to slide with respect to gate22, causing the gate assembly20to expand when in the closed position. A stop38may limit movement of gate segment36with respect to gate22. When valve system10is closed, gate assembly20may expand by an amount sufficient to form a tight seal with seat rings90that blocks fluid communication between upstream end110and downstream end120.

To prevent leaks from the top end of valve system10, an interface between a body-facing surface of bonnet14and an opposite surface of body12may be sealed by an O-ring100and a gasket102. To further prevent leaks at the top end of valve system10, a packing assembly32may be provided so as to surround stem16. With reference toFIG.4, which is a view of section IV inFIG.3, packing assembly32may include a lantern ring24sandwiched between packing material26positioned proximally and distally of lantern ring24. Packing material26may be material that was introduced through packing injection fitting28, for example. Packing assembly32may be configured to form a seal that prevents leaks from traveling toward the proximal end of stem16, without introducing a significant amount of resistance to the motion of stem16in a vertical direction.

FIG.5illustrates an exemplary configuration of a service assembly, such as lubrication port30, as viewed along line V-V ofFIG.1. Lubrication port30may be configured for use as a service point for inline maintenance, as described below, and may be accessible without disconnecting valve system10from upstream and downstream components. For example, lubrication port30may provide access to an interior of body12without disconnecting flanges130or removing bonnet14. Lubrication port30may include a fluid fitting40, such as a so-called giant button head injection fitting. Fluid fitting40may include a coupling end42for receiving a supply device (e.g., a grease gun) for supplying a fluid such as a grease or lubricant. Fluid fitting40may include an axially-extending fluid passage44to direct grease or lubricant supplied from coupling end42. Fluid passage44may include a one-way valve (not shown) such as a ball valve, such that fluid may only pass in a direction from coupling end42toward gate assembly20.

In one aspect, fluid fitting40may be secured by a passage member or lubrication guiding insert50of lubrication port30. Lubrication guiding insert50may protrude from body12to secure fluid fitting40during maintenance. Lubrication guiding insert50may be secured permanently, if desired, via fasteners80and fixing members82. A gasket83may be secured so as to surround a protruding portion of lubrication guiding insert50that extends within body12. Lubrication guiding insert50may include a proximally-located inner recess52at an exterior end of insert50that receives and secures fluid fitting40. In one aspect, side walls of inner recess52may include threading configured to mate with corresponding threading on the outer circumference of a delivery end of fitting40. Alternatively, inner recess52may receive insert50by a friction fit (e.g., press fit) or any other suitable mechanism.

An end of recess52that faces away from body12may include an opening configured to receive lubricating fluid from outside of body12. Recess52may transition to an axially-extending internal channel54, as shown inFIG.5. Internal channel54may extend from the proximal opening of channel54at the bottom of recess52toward an interior of body12, such as a position that supplies lubricating fluid to gate assembly20within body12. Channel54may define a “T” shaped fluid passage that diverts a flow of grease or lubricant into a plurality of separate radial passages58. This “T” shape may be formed by one or more passages58formed within a protruding distal end of lubrication guiding insert50. For example, passages58may be formed as holes formed at the interior end of insert50and extending to an exterior surface of insert50. While two passages58are illustrated, any number of passages58(e.g., three, four, or more) may be provided. If desired, internal channel54may extend to the interior end of lubrication guiding insert50, such that an opening formed at an end of internal channel54supplies lubricating fluid to one or more components of system10, such as gate assembly20.

In one aspect, lubricating fluid may be supplied to a location within the interior of body12where moving components of gate assembly20may be positioned (e.g., by placing valve system10in a closed position). For example, a surface64of gate assembly20may be positioned adjacent to radial passages58when valve system10is closed. Thus, passages58may be positioned to facilitate the introduction of lubricant to one or more high-wear components of gate assembly20when gate valve system10is in this closed position. In particular, lubricant may be directed onto a surface64, which is formed at an interface between moving components of gate assembly20, such as guide plate62, segment36, and/or gate22.

FIG.6is an enlarged view corresponding to features illustrated in section VI ofFIG.3. An upper portion ofFIG.6may correspond to a portion of body12that extends to transverse end140or150. Gate assembly20may be in the closed position such that gate22abuts an inward-facing surface of a ring shaped seat insert66placed within a main body of seat ring90. Seat insert66may be formed of any suitable material (e.g., nylon, reinforced polytetrafluoroethylene, devlon, etc.) configured to form a seal with a portion of gate22or segment36.

Seat ring90may be secured within body12with one or more seat seals70(two shown inFIG.6). Seat seals70may be formed by one or more suitable sealing mechanisms, such as O-rings, ring seals, etc. One or more seat rings90may be configured to receive sealant supplied via one or more injection or sealant paths180. Sealant paths180may be configured to receive sealant supplied from an outside of seat rings90and guide this sealant to a location of seat ring90that has failed. For example, seat ring90may include one or more holes, such as radial passages184that are in communication with an outer circumferential surface of seat ring90.

One or more radial passages184formed in seat ring90may be in communication with one or more axial or longitudinal passages182that extend in a direction that is parallel to an axial direction defined by a radial center of seat ring90. Radial passage184may be formed as one or more holes extending through an outer surface of seal ring90. Radial passage184and/or longitudinal passage182may be configured to supply sealant to a point of failure, such as a leak. For example, as seat insert66may experience wear due to movement and force caused by contact with gate22, seat insert66may fail when exposed to excessive wear, force, or both. Longitudinal passage182may be in fluid communication with a surface of seat insert66to supply sealant in the event of a leak caused by failure of seat insert66.

While longitudinal passage182and radial passages184may be in communication with each other via a single injection port188extending to a transverse end140or150, passages182and184may be provided as separate paths that are configured to receive sealant from a plurality of separate ports, such as a plurality of ports188. For example, a plurality of ports188may be provided in body12to provide paths to each seal70and insert66.

As injection port188may extend to an outer surface of body12, such as a surface of transverse end140and/or150, injection port188may be accessible when valve system10is in the closed position, without the need to remove bonnet14and without disconnecting flanges130from upstream and downstream components. While injection port188is illustrated as having a straight path inFIG.6, injection port188may include one or more turns that facilitate access to an opening of port188and the supply of sealant to a desired location of seat ring90. As represented by the dashed lines inFIG.6, port188may include a widening or tapering opening. If desired, an end of port188configured to receive sealant may include any suitable fitting to facilitate the introduction of sealant. In the event of failure of a seal70resulting in a leak, sealant may be supplied from port188to a failed seal70.

In some embodiments, sealant path180may be configured to receive sealant from an inner circumferential surface of seat ring90, which may include, for example, an introduction port186. In some aspects, introduction port186may include a removable and/or frangible seal or insert that, when removed or punctured, facilitates the injection of sealant. Introduction port186may be useful, for example, when fluid is not supplied to valve system10. When ports186and188are both present, these ports may be aligned with each other or, if desired, at least partially offset from each other.

With reference toFIG.5, an exemplary process for inline maintenance (e.g., maintenance performed without disconnecting flanges130from upstream and downstream components of a pipeline), may include positioning fluid fitting40within recess52of lubrication guiding insert50. With fluid fitting40so positioned, a fluid or lubricant supply device may be fixed to fluid fitting40. For example, a grease or lubrication introduction device, such as a grease gun, may be secured to a proximal end of a fluid passage44located on coupling end42of fluid fitting40. Grease or other lubricant may be injected via fluid passage44such that lubricant flows through fluid passage44and enters an opening at an end of recess52at an opposite end of fitting40. The lubricant may travel through channel54to exit lubrication guiding insert50, either via an opening formed by channel54, or through one or more passages58. The grease or other lubricant may then enter high-wear areas of gate valve system10, such as gate assembly20. In particular, lubricant may be supplied to surface64to reduce friction experienced by moving parts of gate assembly20. This process may be performed, in its entirety, while fluid is present within upstream end110, for example, while gate assembly20is in a closed position resisting a flow of fluid from upstream end110.

With reference toFIG.6, an exemplary process for sealing a leak in gate valve system10may include supplying sealant to an injection port188extending, for example, through transverse end140and/or150. The sealant may travel through port188to one or more radial passages184extending through a radially-outer surface of seat ring90. Radial passages184may supply sealant to a seal70, such as an O-ring. A longitudinal passage182extending from radial passage184may supply sealant to seat insert66. If desired, injection port188may include a path in body that supplies sealant directly to seat insert66. Additionally or alternatively, an injection port186may be provided on an interior of seat ring90to supply sealant to longitudinal passage182.

It will be apparent to those skilled in the art that modifications may be made in the disclosed systems and methods without departing from the scope of the disclosure. Other aspects of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the features disclosed herein. It is intended that the specification and embodiments be considered as exemplary only.