This application claims the benefit of US provisional patent application 62/697,590 filed on June 13, 2018.

Field

The present invention relates to setting tools that can be used in an oil or gas well to secure a zone isolation device in the wellbore.

Summary

A gas operated setting tool in accordance with an embodiment comprises a cylinder, made from tubing, a bottom connector 20, a piston rod 40, and a top cap 30.

Brief Description of the Drawings

Figure 1 shows a cross section of a gas operated setting tool in the unstroked position in accordance with an embodiment of the invention.

Figure 2 shows an inset showing a cross section of a gas operated setting tool's shear ring 50 in the unstroked position in accordance with an embodiment of the invention.

Figure 3 shows a cross section of a gas operated setting tool in the stroked position in accordance with an embodiment of the invention.

Figure 4 shows a cross section of a gas operated setting tool in the unstroked position in accordance with an embodiment of the invention. Detailed Description

A gas operated setting tool in accordance with an embodiment comprises a cylinder, a bottom connector 20, a piston rod 40, and a top cap 30. A cylinder 10 is sometimes called a barrel 10, and a piston rod 40 is sometimes called a mandrel 40.

The outer tool assembly (OTA) comprises a top cap 30, a cylinder, and a bottom connector. The cylinder 10 has a top end and a bottom end. The cylinder's top end connects to the top cap 30and the cylinder's bottom end connects to the bottom connector. When the setting tool strokes the OTA moves axially relative to the piston rod 40 from the unstroked position shown in Figure 1 to the stroked position shown in Figure 3.

The piston rod 40, or mandrel, has a piston section 42, an upper section 41, and a lower section 43. A firing head can attach to the piston rod's upper section 41. A setting adapter can attach to the piston rod's lower section 43. Within the piston rod 40 is a hollow interior space called the power charge chamber 45. The power charge chamber 45 houses the power charge which, when fired, generates gas pressure needed to stroke the setting tool.

As shown in Figure 2, the top cap 30 has an interior surface that engages said piston rod 40 upper section's exterior surface. The engagement surfaces between the top cap 30 and the piston rod's upper section 41 comprise a circumferential shear ring 50 on one surface and a surface feature that comprises a circumferential groove, ledge, or ridge on the other surface. The shear ring 50 on one surface engages the surface feature on the other surface to prevent the top cap 30 from moving axially relative to piston rod's upper section 41, thus preventing the setting tool from stroking while traveling downhole. For some embodiments the piston rod's upper section 41 has the shear ring 50. For other embodiments the shear ring 50 could be part of the top cap's interior surface. The piston rod's shear ring 50 can be integral to the piston rod 40 by, for example, being machined into the piston rod's upper section 41. The shear ring 50 being incorporated into the mandrel streamlines manufacturing. The shear ring 50 also provides an operator with a more efficient way to attach the setting tool in the field. When the setting tool is activated the shear ring 50 will shear, rendering the tool inoperable after a single run.

Before the setting tool is fired the bottom of the piston rod's piston section 42 rests against the bottom connector. The piston rod 40 has port holes 44 that penetrate through the piston rod's piston section 42. The top of the port holes 44 open into the power charge chamber 45 and the bottom of the port holes 44 are against the bottom connector 20 so that the power charge chamber 45 is in fluid communication with the junction between the bottom of the piston rod's piston section 42 and the bottom connector. When the power charge fires gas flows from the power charge chamber 45 through the port holes 44 in the piston rod's piston section 42. The gas pushes directly against the bottom connector 20 and causes the bottom connector20, cylinder 10, and top cap 30 to move downward relative to the piston rod 40 while the piston rod 40 stays in place.

The bottom connector has a top end that is connected to the cylinder. The bottom connector 20 has an inner surface that forms a seal around the piston rod 40. O-rings help form the seal. The bottom connector's seal around the piston rod 40 allows the bottom connector 20 to move relative to the piston rod 40 by sliding. The bottom connector 20 has a bottom end where a setting sleeve can connect to the setting tool.

A setting tool in accordance with an embodiment is intended to be used with electric wireline service.

A prior art setting tool cannot be attached using a shear ring. Because shear ring attachment causes a setting tool to be disposable and reuse is not possible, using a shear ring is not feasible for most prior art setting tools. For some setting tools, geometry prohibits shear ring accommodation because they are not designed to allow shear ring placement.

An embodiment's cylinder 10 can be made from tubing. This feature is unique because design constraints and geometry make the use of tubing impossible for prior art setting tools, for which neither the tubing itself nor its connections will satisfy design requirements and safety factors.

For some embodiments the piston rod 40 is machined from a single piece of bar stock as shown in Figures 1 and 3. For other embodiments, as shown in Figure 4, the piston rod's upper section 41 is made from tubing and has a bottom connection, the piston section 42 has a top connection and a bottom connection, and the piston rod's upper section 43 is made from tubing and has a top connection. The piston rod's upper section 41 bottom connection connects to the piston section's top connection and the piston section's bottom connection connects to the piston rod's upper section 43 top connection. Prior art setting tools cannot have multi-part piston rods made partially from tubing because of design requirements and geometry. Use of tubing reduces material use and machining time to give an embodiment advantages over prior art setting tools in terms of production time and cost. Embodiments have significant geometrical differences from prior art tools and obtain movement differently.

Embodiments provide safety factors that prevent possible failures and disperse gases that actuate the tools differently. The outside tool assembly (OTA) comprises the top cap 30, barrel, and bottom connector. During deployment the shear ring 50 keeps the tool in place until it reaches its target location in the well bore. Then the wireline sends current to the tool. This energizes the igniter which shoots a flame that lights the power charge generating expanding gas in the power charge chamber 45. The gas escapes the power charge chamber 45 through the gas ports 44 that go through the mandrel's piston section 42.

This causes the OTA to break the shear ring 50 and begin moving down the Mandrel. The movement continues setting the plug into the well bore. Plugs with shear values from 28k to 55k attach to the tool by way of a wireline adapter kit (WAK). Once the shear value of the plug has been reached the WAK will shear loose from the plug. The OTA continues moving relative to the mandrel until the cylinder's bleed off port 11 passes the piston section O-ring and the bottom connector 20 O-ring reaches the piston rod lower section's O-ring relief. Gas pressure can then escape into the well bore. The stroke of the tool will stop when the top cap 30 moves far enough down to reach the piston section 42.

Some embodiments of a gas operated setting tool are assembled from four major machined parts: a top cap 30, a mandrel, a barrel, and a bottom connector. The mandrel has a top section that fits into the top cap's hollow interior and interfaces with the top cap 30 with a circumferential shear ledge preventing the tool from actuating during the deployment phase of the downhole trip. There is a bored hole in one end of the mandrel, a chamber 45 to house an explosive charge such as, for example, a "Go style" energetic. At the bottom of this chamber 45 there are two small holes that serve as gas ports 44 that are drilled linear through the middle section of mandrel that functions as the piston. The barrel 10 is a tubular body open on both ends and the bottom connector 20 is open on both ends but contains a sealed section on one end and threads into barrel section forming a lower piston section 42. The mandrel is placed through the formed lower piston section of the barrel 10 and the bottom connector 20 coming to rest with the piston section 42 of the mandrel in direct mechanical contact with the lower piston section of the bottom connector. Specifically, the mandrel's lower section is inserted from above into the barrel 10 and through the bottom connector's opening until the mandrel's piston section 42 contacts the bottom connector. The top cap 30 has two open ends and is place onto the top section of the mandrel and threaded into the barrel 10 securing the tool together and forming the uniform circumference shear ledge between the mandrel and the top cap 30 for the prevention of inadvertent stroking of the tool during deployment. The lower section of the mandrel and the lower section of the bottom connector 20 form a "Baker Style" connection for connecting a zone isolation plug or packer. An embodiment has a barrel 10 and a bottom connector 20 that are separate machined parts that screw together forming a lower piston. This serves two purposes. First, it makes machining the part less expensive. Second, it provides immediate contact with the piston rod's piston section 42 giving immediate movement of the tool when the gas is introduced. This means that the cylinder 10 sees less pressure for a shorter duration because the tool is already stroking before the cylinder 10 feels pressure. In contrast, prior art setting tools must pressurize analogous components significantly before stroking can begin. An embodiment's barrel 10 and bottom connector 20 have direct contact with the mandrel piston and gas vents pass through the mandrel piston coming to the top of the bottom connector's lower piston. Once the gas is introduced the lower portion the OTA immediately begin a downward movement to begin the setting process of the plug or packer. This enables the gas to act in a direct manner to actuate the tool for setting the plug or packer. An embodiment's shear ring 50 prevents movement (anti-preset) of the OTA until the power charge has fired. Prior art setting tools use a screw that penetrates radially to prevent premature movement. An embodiment uses a matching circular ledge machined onto both the top cap 30 and the mandrel to avoid the possibility of damage to the "anti-preset" system during the hook up process of the plug or packer or the hook up to the gun string since rotation of the tool will not damage a circumferential shear ring 50. For safety, it is important for the setting tool to come to the surface without any of the gas that operated the tool remaining inside it. Embodiments have a double pressure relief machined onto the lower portion of the mandrel. An embodiment can use a gas generating power charge that is standard to the industry. An embodiment can accommodate a firing head that attaches to mandrel and then to a gun string that is common to the industry. Unlike prior art setting tools, an embodiment can simultaneously use a "GO Style" gas generating power charge and a "Baker Style" lower end hook up connection.