FIELD OF THE DISCLOSURE

[0001] The present disclosure generally relates to a multi-seat valve and methods for using a multi-seat valve. More particularly, the present disclosure relates to a multi-seat valve, which includes a seal on each side of a sealing member that is secured against a respective pair of seat profiles surrounding a fluid passageway and leak detection passage separating a pair of seat profiles.

BACKGROUND

[0002] Various types of valves may be used to control the flow of fluids through a pipeline. If the fluid(s) also include a mixture of solids, then an adequate seal may be difficult to achieve. Various types of valves have been designed to address the problem associated with achieving an adequate seal in different fluid environments.

[0003] A gate valve typically includes a valve housing for the gate valve in a retracted (open) position and a fluid passageway for connection with a pipeline. As implied by the name, the valve operates like a gate by moving between an open position in the valve housing and a closed position in the fluid passageway. Once closed, the valve is substantially sealed and prevents or obstructs movement of the fluid through the fluid passageway. The ability to achieve an adequate seal is subject to many various gate valve designs. Most gate valve designs, however, only include a single seal or seat on each side of the valve or gate to prevent fluid from moving through the fluid passageway and are not capable of detecting leaks.

[0004] A double block and bleed valve is another type of valve that may be used to replace existing valve technology and generate a double block and bleed (DBB) configuration in the pipeline. DBB valves can isolate both the upstream and downstream movement of fluid using two valves in the pipeline and a third valve positioned in a cavity between the two valves. Once the two valves are closed, the cavity can be drained using the third valve. This is useful for flow diverting, sampling or injection situations, and for maintenance and/or integrity check situations where seat leakage can be monitored through the third valve. If either valve is damaged, for example, leak detection requires bleeding fluid from the cavity through the third valve. This situation may prevent both valves from being inspected for the leak at the same time without diverting around the pipeline containing the DBB valve or worse-shutting down an entire system containing the pipeline. Moreover, DBB valves are expensive to replace and contain a greater number of potential leak paths compared to other types of valves.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The present disclosure is described with reference to the accompanying drawings, in which like elements are referenced with like reference numbers, and in which:

[0006] FIG. 1 is a cross-sectional view illustrating one embodiment of a multi-seat valve in a closed position.

[0007] FIG. 2 is a cross-sectional view illustrating the multi-seat valve of FIG. 1 in an open position.

[0008] FIG. 3 is a cross-sectional view illustrating an enlarged view of the multi-seat valve around 3-3 in FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The present disclosure overcomes one or more of the prior art disadvantages with a multi-seat valve, which includes a seal on each side of a sealing member that is secured against a respective pair of seat profiles surrounding a fluid passageway and leak detection passage separating a pair of seat profiles.

[0010] In one embodiment the present disclosure includes a multi-seat valve, which comprises: i) a body with a chamber and a fluid passageway; and ii) a sealing member moveably positioned within the body, the sealing member including a seal on one side for engagement with a pair of seat profiles on an interior surface of the body surrounding the fluid passageway and another seal on another side for engagement with another pair of seat profiles on another interior surface of the body surrounding the fluid passageway.

[0011] In another embodiment, the present disclosure includes a method for sealing a fluid passageway through a body, which comprises: i) moving a sealing member to a closed position in the fluid passageway; and ii) sealing the fluid passageway to obstruct a flow of a fluid through the fluid passageway by securing a seal on one side of the sealing member against a pair of seat profiles on an interior surface of the body surrounding the fluid passageway and by securing another seal on another side of the sealing member against another pair of seat profiles on another interior surface of the body surrounding the fluid passageway

[0012] The subject matter of the present disclosure is described herein with specificity; however, the description itself is not intended to limit the scope of the disclosure. The subject matter thus, might also be embodied in other ways, to include different structures, steps and/or combinations similar to those described herein in conjunction with other present or future technologies. Moreover, although the term "step" may be used herein to describe different elements of methods employed, the term should not be interpreted as implying any particular order among or between various steps herein disclosed unless otherwise expressly limited by the description to a particular order.

[0013] Referring now to FIGS. 1-3, a cross-sectional view illustrates one embodiment of a multi-seat valve 100 in a closed position (FIG. 1) and an open position (FIG. 2). The multi-seat valve 100 includes a body 102 with a chamber 104 and a fluid passageway 106. The multi-seat valve 100 also includes a sealing member 108 moveably positioned within the body 102. The sealing member 108 includes a seal 110 on one side for engagement with a pair of seat profiles 112 on an interior surface of the body 102 surrounding the fluid passageway 106. This is more visible in FIG. 3, which is a cross-sectional view illustrating an enlarged view of the multi-seat valve around 3-3 in FIG. 1. In FIG. 3, the seal 110 is secured against the pair of seat profiles 112 when the sealing member 108 is at the closed position in FIG. 1. The sealing member 108 includes another seal 114 on another side for engagement with another pair of seat profiles 116 on another interior surface of the body 102 surrounding the fluid passageway 106. Although not shown in FIG. 3, the another seal 114 is secured against the another pair of seat profiles 116 when the sealing member 108 is at the closed position in FIG. 1. In this manner, the pair of seat profiles 112 and the another pair of seat profiles 116 are capable of forming a pair of seal locations 118 and another pair of seal locations (not shown), respectively, when the sealing member 108 is at the closed position in FIG. 1. The seal 110 and the another seal 114 may comprise an elastomer or any other type of elastic polymer suitable for sealing.

[0014] The body 102 includes a leak detection passage 120 with an opening 122 at one end between the pair of seat profiles 112 and an opening 124 at another end outside the fluid passageway 106. The body 102 includes another leak detection passage 126 with an opening (not shown) at one end between the another pair of seat profiles 116 and an opening 128 at another end outside the fluid passageway 106. Additional leak detection passages may be utilized depending on the multi-seat valve 100 specifications. Each leak detection passage 120, 126 may be coupled to a pressure sensor (not shown) at either opening 124, 128 to detect any leaks between the pair of seat profiles 112 and the another pair of seat profiles 116, respectively, when the multi-seat valve 100 is in a closed position (FIG. 1). In this manner, the fluid passageway 106 may be monitored to check for leaks and a leak may be detected without bleeding the fluid, as is typical with DBB valves, by simply detecting a rise in pressure at either opening 124, 128. In the closed position (FIG. 1) and the open position (FIG. 2), each leak detection passage 120, 126 is closed at the one end by the seal 110 and the another seal 114, respectively to obstruct the flow of fluid through each leak detection passage.

[0015] The sealing member 108 includes a gate 130 moveably positioned between a pair of slips 132, 134. Slip 132 includes the seal 110 and slip 134 includes the another seal 114, An operating shaft 136 is connected to the sealing member 108 for moving the sealing member 108 between the closed position in the fluid passageway 106 and the open position in the chamber 104. The operating shaft 136 is connected to the gate 130 in any manner to convey thrust forces for operation. The gate 130 contacts each slip 132, 134 and secures the seal 110 and the another seal 114 against the pair of seat profiles 112 and the another pair of seat profiles 116, respectively, when the sealing member 108 is at the closed position in FIG. 1. In this manner, fluid flowing through the fluid passageway 106 is obstructed to the point of sealing the fluid passageway 106 on each side of the sealing member 108. The operating shaft 136 is coupled to each slip 132, 134 in order to move the sealing member 108 between the closed and open positions and allow a range of retraction of each slip 132, 134 from the respective pair of seat profiles 112 and the another pair of seat profiles 116.

[0016] The multi-seat valve 100 provides additional leak detection between the additional pair of seat profiles 112 and another pair of seat profiles 116. Because the multi-seat valve 100 provides leak detection between the seal 110 and the another seal 114 through stem seal 115, in addition to between the additional pair of seat profiles 112 and another pair of seat profiles 116, it permits the total loss of sealing on one side of the sealing member 108 while performing seal confirmation on the other side of the sealing member 108. As a result, continued operation of the multi-seat valve 100 may be maintained in a leak condition that would otherwise require a system shutdown.

[0017] While the present disclosure has been described in connection with presently preferred embodiments, it will be understood by those skilled in the art that it is not intended to limit the disclosure to those embodiments. It is therefore, contemplated that various alternative embodiments and modifications may be made to the disclosed embodiments without departing from the spirit and scope of the disclosure defined by the appended claims and equivalents thereof.