Downhole Sealing Tool Assembly and Associated Methods

This application claims priority to U.S. Provisional Application No. 63/570,954 filed on Mar. 28, 2024, and entitled, “Downhole Sealing Tool Assembly and Associated Methods”, and which is hereby incorporated by reference in its entirety.

Aspects of the present disclosure relate to downhole sealing tools, such as oil well packers, as well as methods for assembling, setting, using and retrieving such tools. Other aspects relate to the various associated tools used in combination with the downhole sealing tools.

An oil well packer may be defined as a mechanical device for blocking the passage of fluids and or debris in an annular space. Most of this debris emanates from the production zone perforations in a well, can be as large as gravel, but mostly silt and sand coming from the oil-bearing formation.

Downhole packers are well known in the oil and gas industry for sealing an annulus between various weight casings and mandrels at different underground locations in an oil well, for example, to exploit different production zones. Conventional downhole packers include multi-element elastomeric packers, packers including a single elastomeric element having metal or mesh back-ups, and inflatable packers.

Inflatable packers utilize air or other fluid injected into an expandable element to expand the outer shell to reach the interior of the casing. In inflatable packers, the inflation pressure must be higher than the system pressure in order to maintain a positive seal.

In accordance with the present disclosure, there is provided a Downhole Sealing Tool comprising:

The cylindrical mounting surface may extend at least partially along the length of the channel from one end.

At least one of the deformable rings and/or deflection rings may be formed from metal. (e.g., J55 or equivalent, K55 or equivalent, L80/4140, brass, copper, aluminium, or any malleable steel). The deformable rings and/or deflection rings may be formed from elastomer.

The Downhole Sealing Tool may comprise multiple deformable rings, wherein the multiple deformable rings comprise at least one elastically deformable ring and at least one plastically deformable ring.

A said cylindrical mounting surface may face outwards away from the channel. A said cylindrical mounting surface may face inwards towards the channel.

The cylindrical mounting surface may be recessed from an outer diameter of the tubular section (e.g., have a smaller inner diameter than the tubular section).

The cylindrical mounting surface may be recessed from an inner diameter of the tubular section (e.g., have a greater inner diameter than the tubular section).

In a non-compressed configuration, the outer surface of the set of multiple rings may be aligned with a surface of the tubular section. This may help the tool pass through the casing while being positioned.

One or more of the deformable rings may be a cut ring. One or more of the deformable rings may be a continuous ring. A ring may be circularly symmetric.

The Downhole Sealing Tool may be a liner hanger. The outer seal may connect to a casing (e.g., a production casing), and the inner seal may connect to a liner.

The inner seal may be activated prior to positioning downhole. The outer seal may be activated after having been positioned downhole.

The Downhole Sealing Tool may comprise only one seal (e.g., an inner seal or an outer seal).

The Downhole Sealing Tool may comprise a ratchet ring housing having an inner core and an outer core connected by a ratchet ring, which allows the inner core to be moved axially in only one permitted direction with respect to the outer core, and wherein one of the cores is aligned with the set of multiple rings, and the other core is connected to the tubular housing such that, when the ratchet ring is activated in the permitted direction, the multiple rings are compressed. This ratchet ring means that when the seal is activated using pressure, when the pressure is released, the seal remains in an axially compressed configuration. It will be appreciated that a ratchet ring may also be used to activate an inner seal. In such embodiments, the inner core may engage with the set of multiple rings, while the outer core is aligned with the tubular housing.

The Downhole Sealing Tool may comprise a tubular sub section which has a threaded connected for connecting to the tubular section, such that when the threaded connection between the tubular section and the sub section is tightened, the multiple rings are axially compressed.

The Downhole Sealing Tool may comprise a spring bed positioned between the threaded connection and the multiple rings.

According to a further aspect, there is provided a method of activating a Downhole Sealing Tool as described herein, the method comprising: axially compressed the multiple rings from a non-compressed configuration to a compressed configuration, thereby pushing each expandable ring away from the cylindrical mounting surface.

According to a further aspect, there is provided an Entry Guide Assembly comprising:

The access channels may comprise axial elongate channels.

The access channels may comprise slots.

The entry guide may comprise torque lugs, the torque lugs comprising a circularly asymmetric section which can be engaged by a running tool such that the rotation of the Entry Guide about the tubular axis can be controlled.

The entry guide may comprise an annular recess configured to engage with a running tool so that the axial position of the running tool with respect to the Entry Guide is fixed.

The pipe section and the entry guide section may be connected using a threaded connection.

According to a further aspect, there is provided a setting assembly comprising:

According to a further aspect, there is provided a Running Assembly comprising:

The sliding sleeve may be temporarily held in the first position using shear pins.

The running assembly may comprise a sliding sleeve hydraulic chamber at one end of the sliding sleeve, wherein when the sliding sleeve hydraulic chamber is pressurized, a force is exerted on the sliding sleeve along the sliding sleeve guide from the first position to the section position.

The sliding sleeve guide may comprise a closure mechanism for blocking the central channel, thereby allowing the central channel upstream from the closure mechanism to be pressurized.

The closing mechanism may be a ball drop.

The running assembly may comprise multiple axially oriented push rods.

The running assembly may comprise one or more push rod hydraulic chambers for activating the push rods.

The running assembly may comprise torque lugs, the torque lugs comprising a circularly asymmetric section which can be engaged by an entry guide such that the rotation of the entry guide about the tubular axis can be controlled.

According to a further aspect, there is provided a Pawl Grip assembly comprising:

The first tubular assembly may comprise an interior recess for receiving the sheared pawl insert and expanded pawl.

The pawl may comprise serrated inwardly facing gripping surfaces.

The pawl insert may have an annular shape.

The pawl ring may have a gap to allow the pawl ring to bend inwardly as the pawl ring engages with the inclined surface of the pawl insert. The pawl ring may be a split ring.

The deformable rings may be continuous or have a cut (e.g., be a piston, or split ring). The cut may be a skive cut, a butt cut, a step cut, or any other ring cut type.

Using multiple deformable rings within a single seal may help keep the Downhole Packer Tool aligned with the component (e.g., casing and/or liner) to which the Downhole Packer Tool is sealing.

The closing mechanism may comprise a flap valve.

The delivery assembly may comprise three sub-assemblies: a Sacrificial Housing sub-assembly, a Downhole Sealing Tool sub-assembly, and a Running Tool sub-assembly.

After the Downhole Sealing Tool sub-assembly is set downhole, only the Running Tool sub-assembly may be returned to surface. The Running Tool sub-assembly may comprise a drop Ball Seat and Ball, which is also returned to the surface. The Running Tool sub-assembly may be used repeatedly for setting multiple Downhole Sealing Tools.

The Downhole Sealing Tool may be deployed using drill pipe or a service rig work string. The Downhole Sealing Tool may be deployed on production tubing (e.g., 5½ inch).

The Delivery System may be activated by surface hydraulic means following a Ball drop procedure.

The Sacrificial Housing Sub-assembly may be able to carry up to 3000 m or more of liner (e.g., 7.0 inch, 23.0 lb/ft) suspended below.

The Delivery Assembly may be configured to fit within a pipe having a diameter between 4-12 inches. The Delivery Assembly may have a length between 40-80 inches. The Downhole Sealing tool may have a length of between 10-25 inches. Each ring may have a width of between 0.5-2 inches. The downhole tool may be capable of sealing to outwardly to a diameter of between 6 and 10 inches. The down hole tool may be cable of sealing to inwardly to a diameter of between 4 and 8 inches. The Downhole Sealing Tool may have a size of 9⅝″×7″, 11¾″×9⅝″ or 7″×4½″, where the first number in each pair represents the inner diameter which the outer seal is sealing against (e.g., the outer casing), and the second smaller number in each pair represents the outer diameter which the inner seal is sealing against (e.g., the liner).