Wells – Processes – Placing or shifting well part
Reexamination Certificate
2000-04-24
2001-11-13
Bagnell, David (Department: 3672)
Wells
Processes
Placing or shifting well part
C166S117500, C166S182000, C175S061000
Reexamination Certificate
active
06315054
ABSTRACT:
FIELD OF INVENTION
The present invention relates and discloses assemblies and methods for locating lateral wellbores drilled from a main wellbore casing for positioning members with respect to the lateral wellbore and the main wellbore casing and for orientating and positioning reentry, completion and workover devices for entry into the lateral wellbores. These assemblies and methods include generally the presence of a first wellbore casing, a window formed in and through the first wellbore casing and a sill of the window formed in the first wellbore casing defining the window in the first wellbore casing and with the sill being convergently curved up hole to form an up hole apex in the first wellbore casing, at least a second wellbore proximate and in communication with the window and extending from the first wellbore casing, a tubular string, a housing member movably disposed in the first wellbore casing for being run into the first wellbore casing by the tubular string and connected to the tubular string, orientation and positioning members connected to the housing member for orientating and positioning the housing relative to the window upon up hole movement of the orientation and positioning member, and completion tools connected to the tubular string for movement into the first wellbore casing for completion. This present invention further includes devices connected to the tubular string for movement into the first wellbore casing and at least a second wellbore, and has selective separating mechanisms connected to the housing member for selective separation of the devices connected to the tubular string for allowing their movement into the second wellbore. Also this present invention further includes deflector members connected to the housing for deflecting the devices for reentry, workover, and reentry and completion as the devices and tubular string are selectively separated from the housing and advanced down hole into the deflector members and deflected by the deflector member into the at least second wellbore member. Further this present invention includes the presence of a deflector connected between the completion tools set above and below the at least second wellbore member which are set in the main wellbore casing for allowing reentry of tubing into the at least second wellbore member at any time after the setting of the completion tools in the main wellbore casing. Also this invention includes a sleeve with at least one seal for being moved into position to close the window from communication with the second wellbore to protect the second wellbore from being damaged from activity in the main well bore. Further this present invention provides a release for disengaging the orientation and positioning member to allow movement and removal of the orientation and positioning member out of the window for movement of the housing member in the well when desired.
1. Background of the Invention
Drilling and completion of horizontal wells in recent years has resulted in the dramatic improvements in the production and recovery of hydrocarbons from both new and older wells. Although horizontal wells have been accepted by the industry as a proven and cost effective means to increase production and maximize ultimate recovery of hydrocarbons from a reservoir while lowering the cost, they are expensive. It has, however, been proven that although horizontal wells cost significantly more to drill and complete than vertical wells, a horizontal well frequently improves production by a factor of 5 to 10 times in suitable reservoirs, such as those which are naturally fractured or in heavy oil applications. The economics associated with horizontal drilling are so favorable in many areas of the world that the drilling of vertical wells in these areas has become relatively rare. The increases in both the production and ultimate recovery of hydrocarbon reserves associated with horizontal drilling generally minimizes the number of well locations and infrastructure required to develop an oil and gas field. This is particularly important in high cost or environmentally sensitive areas, such as offshore locations, where reducing the number of platforms often results in significantly reduced investment and lower operational costs. Other areas which are particularly applicable for horizontal development include reservoirs in urban areas, wildlife preserves, and permafrost zones. In addition horizontal drilling allows optimization of water injection efficiency and the development of thin, stacked reservoirs that would otherwise require many vertical wells, as well as reservoirs with coning problems, in which horizontal drilling allows laterals to be optimally spaced for the fluid contact.
The industry has come to accept that multilateral wells are the most cost effective means to deliver horizontal wellbores. In addition this multilateral approach minimizes the environmental impact and amount of surface infrastructure required to develop an oil field. The reason is simple. A multilateral well allows multiple hydrocarbon reservoirs to be developed through the drilling of only a single main wellbore. Thus by using many lateral wells ie., multilateral wells, the advantages of horizontal drilling can be maximized on a single main well bore.
As a result of this multilateral wells have become increasingly popular over the last few years, both in the application as new wells to develop fields, as well as in the reentry of existing wells in established fields to increase production through stimulation, workover, and deepening activities. This increase is largely due to the lower oil and gas pricing levels that currently exist, which is therefore driving the industry to utilize the most cost effective means to produce hydrocarbon reserves. In addition, public awareness of the impact that drilling and production operations have on the environment has provided an additional incentive for the industry to minimize the number of wells and infrastructure required to develop oil & gas reserves. However, until recently individual laterals were not cased or tied back to the main production casing. This meant that it was difficult or impossible to reenter these laterals in the event that a workover, clean out or stimulation was required.
The technology now exists to drill, tie back and complete multiple laterals in vertical, deviated, directional or horizontal wells either at the time the well is drilled or at a later time in the life of the well. More than one lateral can now be “kicked off” at the same elevation of the main wellbore casing, and there is no limit as to how many laterals can be installed from a single main casing. Using this multiple lateral technology a customized drainage architecture can be installed which minimizes the distance that the hydrocarbons must travel to reach the wellbore and assures that the reservoir can be produced in the most efficient and cost effective manner. However in order to receive the full benefits of these advancements in the drilling technology, the laterals or multilateral must be able to be selectively reentered quickly and reliably, and completed in a cost effective manner.
For the above mentioned reasons, the industry is placing ever increasing dependence on multilateral well completions. As such, there is a great demand within the industry for advancing the technical capabilities of the completion systems which are available. The completion technology for the installation of lateral junctions in competent formations is well known. A primary barrier to the increased use of multilateral technology has been limitations in the completion options available, particularly in those situations in which a sealed junction is required to effectively produce a reservoir. Situations in which hydraulically sealed lateral junctions are desirable include unconsolidated or weakly consolidated formations, in order to avoid collapse of the junction or in those junctions in which water injection is planned, or when the influx of formation fluids into the primary casing is unacceptabl
Bagnell David
Parks & Associates P.C.
Walker Zakiya
Weatherford Lamb, Inc
LandOfFree
Assembly and method for locating lateral wellbores drilled... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Assembly and method for locating lateral wellbores drilled..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Assembly and method for locating lateral wellbores drilled... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2580940