Methods and systems for a vent within a tool positioned within a wellbore

Systems and methods to maintain constant pressure within a chamber within a tool via a sliding seal, wherein the seal moves to increase or decrease the size of the chamber.

BACKGROUND INFORMATION

Field of the Disclosure

Examples of the present disclosure relate to systems and methods for a vent positioned within a wellbore. More specifically, embodiments related to a vent through the circumference of the tool positioned below a packer pair that is configured to set based on a pressure differential within a tool.

Background

Hydraulic injection is a method performed by pumping fluid into a formation at a pressure sufficient to create fractures in the formation. When a fracture is open, a propping agent may be added to the fluid. The propping agent, e.g. sand or ceramic beads, remains in the fractures to keep the fractures open when the pumping rate and pressure decreases.

To create the sufficient pressure to create fractures straddle packers may be used to isolate an area within the formation. Conventionally, straddle packers are set mechanically or based on a pressure differential between an inner diameter of the tool and an annulus. However, to create the pressure differentially it is typically necessary to create a column of fluid within the tool. To remove the column of fluid within the tool, it is required to reverse circuit fluid through a port positioned between or above the packer pair. This conventional process can take a substantial amount of time, which may shut down a wellbore for a sufficient period of time.

Accordingly, needs exist for systems and methods for fracturing systems with a vent that is positioned below a packer pair that is configured to set based on a pressure differential within the tool.

SUMMARY

Examples of the present disclosure relate to systems and methods utilizing a pressure differential open and close a vent extending through a circumference of the tool. In embodiments, the vent may be positioned below a packer pair, wherein the packer pair extends across an annulus. The tool may include a filter, vent, sliding sleeve, adjustable member, and piston.

The filter may be a passageway that is configured to limit impurities from flowing into a chamber housing the adjustable member. The passageway housing the filter may be positioned between a straddle packer pair, such that the passageway is positioned within an isolated zone. Through the passageway the chamber housing the adjustable member may be in communication with the annulus between the straddle packer pair, such that the chamber has a first pressure that is equal with that of the annulus pressure between the pair of packers.

The vent may include a plurality of orifices positioned proximate to a distal end of the tool, wherein the plurality of orifices extend through a circumference of the tool. The plurality of orifices may be configured to allow communication between an annulus positioned outside of the tool and the inner diameter of the tool. In an open mode, a distal end of the sliding sleeve may be offset from the vent, which allows the vent to be exposed. When exposed, the vent allows for communication between the inner diameter of the tool and the annulus. In a closed mode, the distal end of the sliding sleeve may be aligned with the vent, which may cover the vents and not allow communication between the inner diameter of the tool and the annulus. In embodiments, the vent may be positioned below a packer pair

The sliding sleeve may be positioned within the inner diameter of the tool, and may be configured to slide between the proximal end and the distal end of the tool. In embodiments, the sliding sleeve may move towards the distal end of the tool responsive to a pressure differential between the inner diameter of the tool and the annulus between the straddle packer pair being greater than a pressure threshold. When the pressure differential is greater than the pressure threshold, the sliding sleeve may move towards the distal end of the tool and cover the vent. The sliding sleeve may return towards the proximal end of the tool responsive to the pressure differential being less than the pressure threshold, wherein when returning towards the proximal end of the tool the sliding sleeve may uncover the vent. In embodiments, a first end of the sliding sleeve may be configured to be positioned between the straddle packer pair, and the second end of the sliding sleeve may be configured to be positioned below both packers within the packer pair.

The adjustable member may be a spring configured to compress and elongate based on the pressure differential between the inner diameter of the tool and the annulus between the packer pair, wherein the adjustable member may compress when the pressure differential is greater than a spring force and the adjustable member may return to a resting, elongated state, when the pressure differential is less than the spring force. The adjustable member may be configured to be positioned within a chamber that is in communication, via the filter, with an annulus between the straddle packer pair. Responsive to the pressure differential being above a pressure threshold, the adjustable member may compress. Responsive to the pressure differential being below the pressure, the adjustable member may elongate from the compressed state to an elongated state. In embodiments, the pressure differential may be associated with a spring force that is generated by the adjustable member that is a constant force in a direction from the distal end of the tool towards the proximal end of the tool. The adjustable member may be coupled to the sliding sleeve, wherein the sliding sleeve may move responsive to the adjustable member compressing and elongating. When the adjustable member compresses, the sliding sleeve may move towards the distal end of the tool, and when the adjustable member elongates the sliding sleeve may move towards the proximal end of the tool.

The piston may be positioned on a first end of the sliding sleeve. A first diameter across the piston may be greater than a second diameter across the inner diameter of the tool above the piston. This increase in area may be configured to increase the pressure within the inner diameter of tool that is aligned with the piston, which may enable the pressure differential between the piston and the annulus outside of the tool to be greater than the pressure threshold, while the pressure above the piston within the tool may be less than the pressure threshold.

DETAILED DESCRIPTION

FIG. 1depicts a tool100in a first mode, according to an embodiment. In the first mode, a vent120positioned proximate to a distal end104of tool100may be uncovered. In embodiments, responsive to generating a pressure differential between the inner diameter of tool100and an annulus between a packer pair being greater than a pressure threshold, a sliding sleeve130may move to cover the vent120. By covering vent120, tool100may be configured to generate sufficient pressure within the inner diameter of tool100during a stimulation and/or production stage. After the stimulation and/or production stage, vent120may be uncovered. By uncovering the vent120, a pressure differential between the inner diameter of tool100and the annulus may quickly and efficiently equalize leading to tool100being able to reset quicker. Tool100may include a filter110, vent120, sliding sleeve130, adjustable member140, and piston150.

Filter110may be a passageway that is configured limit impurities from flowing into a chamber housing adjustable member140. The passageway housing filter110may be positioned between a straddle packer pair, such that the passageway is positioned within an isolated zone. A lower straddle packer of the pair may be positioned between filter110and vent120, and an upper straddle packer of the pair may be positioned between filter110and a surface of the well. By extending a filter housing securing filter110in place110from the chamber to the annulus, communication may be enabled between the annulus and the chamber housing adjustable member140. This may enable the chamber housing adjustable member140to have a pressure that is equal to the isolated zone in the annulus between the straddle packer pair.

Vent120may include a plurality of orifices positioned proximate to a distal end104, wherein the plurality of orifices extend through a circumference of tool100. The plurality of orifices may be configured to allow communication between an annulus positioned outside of the tool at a location below the packer pair and the inner diameter of tool100. In an open mode, a distal end of sliding sleeve130may be offset and positioned above vent120, wherein the distal end of sliding sleeve is positioned closer to the surface of the well than vent120. This may allow the plurality of orifices to be exposed, permitting communication between the inner diameter of tool100and the annulus. In a closed mode, the distal end of the sliding sleeve130may be positioned below vent120, which may cover the plurality of orifices. This may limit communication between the inner diameter of tool100and the annulus.

Sliding sleeve130may be positioned within the inner diameter of the tool, and may be configured to slide between the proximal end102and the distal end104of the tool100. In embodiments, sliding sleeve130may move towards distal end104of tool100responsive to a pressure differential between the inner diameter of tool100and the annulus between the straddle packer paid being greater than a pressure threshold, wherein the pressure threshold is associated with a spring force generated by the adjustable member140. When the pressure differential is greater than the pressure threshold, sliding sleeve130may move towards distal end104of the tool and cover vent120. Sliding sleeve130may return towards the proximal end102of tool100responsive to the pressure differential being less than the pressure threshold, wherein when returning sliding sleeve130towards proximal end102of tool100may uncover the vent120. In embodiments, a first end of the sliding sleeve130may be configured to be positioned between the straddle packer pair, and the second end of sliding sleeve130may be configured to be positioned below both packers within the packer pair.

Seal132may be configured to be positioned adjacent to and/or below vents120when sliding sleeve130is moved towards distal end104of tool100. Seal132may have a length that is greater than that of a circumference of the plurality of orifices of vent120. This may limit, restrict, etc. the amount of fluid that can be communicated between the inner diameter of tool100and the annulus.

Adjustable member140may be configured to compress and elongate based on the pressure differential between the inner diameter of the tool and the annulus between the packer pair. Adjustable member140may be configured to be positioned within a chamber that is in communication, via filter110, with an annulus between the straddle packer pair. In embodiments, the chamber housing the adjustable member140may be isolated from the inner diameter of the tool, allowing for a pressure differential to be formed between the inner diameter of tool100and the annulus. Responsive to the pressure differential between the inner diameter of the tool and the annulus between the packer pair being above a pressure threshold, adjustable member140may compress. Responsive to the pressure differential between the inner diameter of the tool and the annulus between the packer pair being below the pressure, adjustable member140may elongate from the compressed state to an elongated state.

In embodiments, the pressure threshold may be associated with a spring force that is generated by adjustable member140that is a constant force in a direction from distal end104of tool100towards the proximal end102of tool100. Adjustable member140may be coupled to the sliding sleeve130, wherein sliding sleeve130may move responsive to adjustable member140compressing and elongating. When the adjustable member compresses, the sliding sleeve130may move towards the distal end of the tool, and when the adjustable member elongates the sliding sleeve130may move towards the proximal end of the tool.

Piston150may be positioned on a first end of sliding sleeve130. A first diameter across the piston may be greater than a second diameter across the inner diameter of the tool above piston150. This increase in area may be configured to increase the pressure within the inner diameter of tool that is aligned with piston150, which may enable the pressure differential between the piston and the annulus outside of the tool to be greater than the pressure threshold associated with the spring force.

FIG. 2depicts tool100in the second mode, according to an embodiment. Elements depicted inFIG. 2may be substantially similar to those described above. Therefore, for the sake of brevity a further description of these elements is omitted.

In the second mode, sliding sleeve130may have moved towards distal end104based on the pressure differential within the annulus between the packer pair and the inner diameter of tool100being greater than the spring force applied by adjustable member140in an opposite direction. Based on the pressure differential increasing, a ledge210on sliding sleeve140may apply forces in a direction towards distal end104to compress adjustable member140.

Responsive to moving sliding sleeve130, vent120may be covered by sliding sleeve130and sealed. This may allow for a production stage within the isolated zone between the packer pair, while not allowing for communication with an annulus through vent120.

In embodiments, the pressure differential may increase to be greater than the pressure threshold responsive to flowing fluid through the inner diameter of the tool100to set the pair of packers, wherein the pressure increases within the inner diameter of the tool100after the zone has been isolated. When the flow of fluid ceases through the inner diameter of tool100, the annulus between the packer pair and the inner diameter of the tool may have equalized pressure, which enables the spring force to be greater than the pressure differential. This may enable tool100to reset, moving sliding sleeve130towards proximal end102, and uncovering vent120.

FIG. 3depicts a method300for a system utilizing pressure differential to open and close a vent, according to an embodiment. The operations of method300presented below are intended to be illustrative. In some embodiments, method300may be accomplished with one or more additional operations not described, and/or without one or more of the operations discussed. Additionally, the order in which the operations of method300are illustrated inFIG. 3and described below is not intended to be limiting. Furthermore, the operations of method300may be repeated for subsequent valves or zones in a well.

At operation310, a fluid flow rate through the inner diameter of a tool may increase, which may cause a pair of straddle packers to set.

At operation320, a pressure differential between an annulus between the packer pair and the inner diameter of the tool may increase to be greater than a spring force in a second direction.

At operation330, the pressure differential may cause a ledge on a sliding sleeve to compress the spring, and allow the sliding sleeve to move towards a distal end of the tool. Responsive to the sliding sleeve moving, the sliding sleeve may cover a vent.

At operation340, fluid may cease flowing through the inner diameter of the tool, allowing the pressure within the annulus and the inner diameter of the tool to decrease to be less than the spring force.

At operation350, the spring force may elongate and apply pressure against the ledge of the sliding sleeve. This may cause the sliding sleeve to move towards the proximal end of the tool and uncover the vent.

At operation360, fluid may be communicated between the annulus and the inner diameter of the tool at a location below the packer pair. This may allow the packer pair to reset more efficiently and also allow pressures between the inner diameter of the tool and the annulus to more quickly equalize.