1. Field of the Invention
The present invention relates to an apparatus and method using expandable tubulars to complete a well. More particularly, the invention relates to the installation of an expandable sand screen. More particularly still, the invention relates to a single trip installation process to set a liner hanger in a wellbore and then expand a sand screen.
2. Description of the Related Art
Hydrocarbon wells are typically formed with a central wellbore that is supported by steel casing. The casing lines a borehole formed in the earth during the drilling process. An annular area formed between the casing and the borehole is filled with cement to further support and form the wellbore.
Some wells are produced by perforating the casing of the wellbore at selected depths where hydrocarbons are found. Hydrocarbons migrate from the formation through the perforations and into the wellbore where they are usually collected in a separate string of production tubing for transportation to the surface of the well. In other instances, a lower portion of a wellbore is left open and not lined with casing. This xe2x80x9copen holexe2x80x9d completion permits hydrocarbons in an adjacent formation to migrate directly into the wellbore where they are subsequently raised to the surface, possibly through an artificial lift system.
Open hole completions can provide higher production than cased hole completions and they are frequently utilized in connection with horizontally drilled boreholes. However, open hole completions leave aggregate material, including sand, free to invade the wellbore. Sand entering an open hole wellbore causes instability within the open hole which enhances the risk of complete collapse. Sand production can also result in premature failure of artificial lift and other downhole and surface equipment due to the abrasive nature of sand. In some instances, high velocity sand particles can contact and erode lining and tubing.
Sand can also be a problem where casing is perforated to collect hydrocarbons. Typically, casing is perforated with a perforating assembly or xe2x80x9cgunsxe2x80x9d that are run into a wellbore and fired to form the perforations. Thereafter, the assembly is removed and a separate assembly is installed to collect the migrating hydrocarbons. The perforations also create a passageway for aggregate material, including sand to enter the wellbore. As with an open wellbore, sand entering the cased wellbore can interfere with the operation of downhole tools, clog screens and damage components, especially if the material enters the wellbore at a high velocity.
To control particle flow into a wellbore, well screens are often employed downhole. Conventional wellscreens are placed adjacent perforations or unlined portions of the wellbore to filter out particulates as production fluid enters a tubing string. One form of well screen recently developed is the expandable sand screen (ESS). In general, the ESS is constructed of different composite layers, including a filter media.
A more particular description of an ESS is found in U.S. Pat. No. 5,901,789, which is incorporated by reference herein in its entirety. That patent describes an ESS which consists of a perforated base pipe, a woven filtering material, and a protective, perforated outer shroud. Both the base pipe and the outer shroud are expandable, and the woven filter is typically arranged over the base pipe in sheets that partially cover one another and slide across one another as the sand screen is expanded. The ESS is expanded by a cone-shaped object urged along its inner bore or by an expander tool having radially outward extending rollers that are fluid powered from a tubular string. Using expansion means like these, the ESS is subjected to outwardly radial forces that urge the expanding walls against the open formation or parent casing. The components of the ESS are expanded past their elastic limit, thereby increasing the inner and outer diameter of the tubular.
A major advantage to the ESS in an open wellbore is that once expanded, the walls of the wellbore are supported by the ESS. Additionally, the annular area between the screen and the wellbore is mostly eliminated, and with it the need for a gravel pack. A gravel pack is used with conventional well screens to fill an annular area between the screen and wellbore and to support the walls of the open hole. With an ESS, the screen is expanded to a point where its outer wall places a stress on the walls of the wellbore, thereby providing support to the walls of the wellbore to prevent dislocation of particles. Solid expandable tubulars are oftentimes used in conjunction with an ESS to provide a zonal isolation capability. In addition to open wellbores, the ESS is effectually used with a perforated casing to control the introduction of particulate matter into the cased wellbore via the perforations.
While an ESS can reduce or eliminate the inflow of particles into a wellbore, the screen must be installed and expanded in order to operate effectively. Any delay in the installation permits additional time for sand to enter the wellbore and the time period is especially critical between the formation of perforations in a casing wall and the expansion of screen against the perforations. The delays are especially critical if the newly formed wellbore is placed in an over balanced condition prior to expanding the ESS. An overbalanced condition permits fluids to enter the formations and hamper later production of hydrocarbons.
In current installation procedures of ESS the operator makes two trips downhole. In the first trip, the operator sets a liner hanger to secure the ESS in the wellbore. After returning from the first trip downhole, the operator must make a second trip with an expansion tool in order to expand the ESS.
There are several disadvantages to a multiple trip installation procedure. The biggest disadvantage relates to expensive downtime necessary to make both trips. Also, a delay between the first and second trips can cause well control problems due to fluid loss. For example, pressurized fluid in the wellbore used to actuate various mechanical components during the installation process can enter the formations causing formations to clog-up or collapse, restricting the flow of hydrocarbons. In addition, loss of drilling fluid increases the completion cost of the well. In other instances, a delay between perforating a casing and expanding a sand screen against the perforations increases the likelihood that solids from the formations will enter the wellbore. In addition to the foregoing, packers used to fix an ESS in a wellbore often have a relatively small inside diameter. These packer-like components remain in the wellbore and can cause access problems for remedial work required below the suspension device.
There is a need therefore, for an apparatus to reduce the time needed to install an expandable sand screen in a wellbore. There is a further need to set a sand screen in a wellbore and then expand the sand screen in a single trip. There is a further need for a method and apparatus to facilitate the setting of a liner hanger in a wellbore prior to the expansion of an ESS. Still further, there is a need for an apparatus to minimize the exposure to formation solids before expanding the ESS. There is a further need for a single trip ESS apparatus that uses a liner hanger that does not restrict access within the wellbore after the ESS is expanded.
The present invention includes a method and apparatus for installing and expanding an ESS in a wellbore in a single trip. In one aspect of the invention, a liner hanger and expandable screen are provided and are run into the wellbore with an expansion tool and work string. After the hanger is set, the expansion tool is used to expand the screen. In another aspect, an annular area within the apparatus is utilized in order to set the hanger with pressurized fluid. Thereafter, cup packers used in sealing the annulus are lifted from the liner prior to expanding the screen. The expansion tool and work string are then removed leaving the expanded ESS and hanger in the wellbore.