Patent Application
20130020092
The field of the invention is tools operated at a subterranean location with an applied magnetic field that also have an automatic timed actuation feature and an ability to pause actuation if there are issues that delay placement while offering the ability to subsequently shift from pause mode to actuation mode when the tool is at the desired location.
Subterranean tools need to be put into position into a wellbore before they are actuated. One such tool is a packer, which is used to isolate between or among zones for a variety of reasons including well control and production. Depending on the depth that the packer is to be set and assuming no unforeseen problems in running the packer to the target depth it is possible to have a packer automatically set after an allotted time on a timer that is tied to the setting mechanism. There are a variety of known ways to set a packer such as by using wellbore hydrostatic pressure, relative movement induced in a variety of ways, expansion and inflation, to name a few ways.
Triggering such setting of the packer can involve a locking mechanism that is unlocked such as for example with a magnetic field generated by a permanent magnet that is pumped downhole using opposed packing elements 76 and 78 as shown in
The present invention relates to tools that can be triggered to set on a timer that can be stopped if there is a problem in getting the tool into position within the preset time. The system also has the capability of having the timer restarted to count off the remaining time or to go immediately to actuate the setting mechanism for the tool. In the preferred embodiment the tool is a packer that is set with a reaction that generates gas pressure to create the movement to set the packer. The reaction is preferably initiated by the application of a magnetic field that triggers a valve to open to allow the reactants to mix to generate the gas that sets the packer. The magnetic field can be brought in close proximity with the tool with a permanent or electromagnet that can be delivered either on wireline or slickline or can be mounted internally to an object such as a ball or a plug that can reach the tool by gravity in a vertical well or can be aided in moving to the desired location with circulation. Optionally, the object transporting the magnet can land on a seat in the string that was used to place the packer to provide an emergency capability to set the packer with pressure on the seated object.
Those skilled in the art will better appreciate the details of the invention from a review of the preferred embodiment description and associated drawings while recognizing that the full scope of the invention is to be determined from the appended claims.
A subterranean tool that is self contained for actuation can be run into a desired location on an automatic set mode controlled by a timer. If a problem develops in getting the tool to the desired location in time a magnetic field can be brought to bear on the tool to stop the timer before the tool actuates. Once the tool is subsequently positioned at the desired location another magnetic field can be brought to bear near the tool to set it. Alternatively, the tool can be run to the desired location without activation with the timer and then the magnetic field can be brought to the tool to set it. The magnetic field can be lowered to the tool with wireline or can be dropped or pumped past the tool to actuate the tool. Optionally the field can be generated from within an object that ultimately lands on a seat to provide a backup way to set the tool using tubing pressure in the string used to place the tool.
a-1e shows the set position of the tool in a section view;
a-2e is the view of
Referring to
As shown in
Referring back to
As described above the generated gas from the reaction is preferably used to release pin 34 so that hydrostatic pressure can be used at the entry ports 36, 37 and 39 to ultimately put the seal/slip assembly 66 in the set position. While a reaction that generates gas can be one way to release the lock in response to a magnetic field as a signal, there are alternatives that can be used in conjunction or as a replacement to the gas generating reaction to release the pin 34 or even to provide the total force needed for a setting of the seal/slip 66. For example, if using an object 22 that lands on a seat 24 it allows the tubing passage 26 to be pressured up. The lock that comprises the pin 34 held by lock sleeve 28 can be urged to move from the
Those skilled in the art will appreciate that any type of tool can be magnetically set or have its ability to automatically set based on a timer interrupted with a further ability to set later using a magnetic signal. As a backup the magnetic signaling device can also land on a seat in the tubing to allow pressure buildup in the tubing to trigger a set for the tool. In one way this is done is through wall flexing to release a lock so that the tool can be set with a potential energy force that can be annulus hydrostatic or a compressed gas or spring located in the tool. Alternatively, in some applications where the annulus can be pressurized, the lock can be released from the annulus with applied annulus pressure and the tool then set with pressure differential using annulus pressure. In this case the sleeve 28 is moved with applied annulus pressure above the expected hydrostatic at the setting depth to trigger unlocking and setting the tool.
If triggering the lock with a magnetic field is used the permanent or electromagnet or other source used to generated the recognized field can be delivered on a variety of conveyances or dropped or pumped to the tool. The timer T if triggered when the tool 18 is run in will simply unlock the lock in the form of pin 34 without need of a magnetic field to trigger lock release. Preferably a discrete magnetic field is used to stop the timer T as opposed to providing the signal to unlock so that the tool 18 then sets. These differences can be in the wavelength or frequency of the field or other ways detectable by the processor associated with the tool 18.
Other types of energy fields are envisioned such as radio frequency, nuclear energy, as well as various types of electric and magnetic fields that can be detected without having a port in a tool mandrel at a location outside the mandrel. The preferred reactant is water reactive aluminum alloy material known as TAFA and sold by Tafa Inc. of New Hampshire, USA.
While the focus of the preferred embodiment has been the use of magnetic fields the scope of the invention encompasses a control device that can set or actuate the tool that has the capability of being stopped before a preplanned condition of any sort occurs and then can be triggered at a later time to set or actuate the tool. If a timer is involved and the time has not expired, the timer can be halted. Thereafter there are options to either restart the timer for the remaining time, reset the timer for the originally set time or some other interval of time or to simply bypass the timer and go directly to tool actuation. If there is no timer and the triggering event has not yet occurred then a signal can stop the tool from setting and a later signal that is the same or different can allow the tool to actuate. The initial triggering event can be pressure, temperature, pH or other wellbore conditions that preexist or that can be created at the desired location such as vibration, pipe wall strain, acoustic pressure pulses or radio frequencies. In essence the setting condition or programmable event can be the timer or timers or existing or created well conditions. When using well conditions and stopping the setting the options for setting the tool are to enable the system to wait for the well condition to exist or to simply enable the tool to immediately set on receipt of the signal. The signal can arrive in the form of balls that are dropped, drop bars, plugs or wiper plugs to name a few options. For most of these options the orientation of the object at well insertion is not material to the ability of the sensor to detect the targeted condition, such as a magnetic field for example. The signal transmitter can be delivered to the desired location by gravity, fluid flow, wireline, electric line, slickline or a tractor, to name a few options. The sensor for the signal can be mounted integrally to a string or in a separate tool mandrel that is part of the string. When using a magnetic signal, for example the housing for the sensor of that signal should not create interference. Thus, a housing for a magnetic field sensor created by a permanent or electromagnet, for example, can be contained in a non-magnetic housing. The sensor for the target condition can be at least partially exposed to well fluids in a tubular string or in a surrounding annular space. Wall openings in the string are preferably avoided to enhance the certainty of separation between the tubing fluid and the surrounding annulus fluids.
The above description is illustrative of the preferred embodiment and many modifications may be made by those skilled in the art without departing from the invention whose scope is to be determined from the literal and equivalent scope of the claims below.
