Abstract:
In one aspect, a wellbore system is disclosed that in one non-limiting embodiment includes a first wellbore capable of producing a fluid from a first formation, a second wellbore intersecting the first wellbore at a junction, wherein the second wellbore is an open hole and capable of producing a fluid from a second formation and a sand screen at the junction configured to inhibit particles larger than a selected size from flowing from the second wellbore and the junction into the first wellbore.

Description:
BACKGROUND 
     1. Field of the Disclosure 
     This disclosure relates generally to wellbore systems, including multilateral wellbore systems that inhibit flow of particles over a certain size from one wellbore to another wellbore. 
     2. Background of the Art 
     Wells or wellbores are drilled in subsurface formations for the production of hydrocarbons (oil and gas). In some cases, multilateral wells are formed, wherein one or more wells are formed from a main wellbore. Sometimes lateral wellbores are also formed from one or more of the other lateral wellbores. Such a wellbore system is generally referred to a “multilateral wellbore” or a “multilateral wellbore system.” Typically, the main wellbore is a cased wellbore, in that, it is lined with a metal casing (typically a jointed metallic tubular). In some cases the lateral wellbore is not lined with a casing, i.e., it is left as an open hole. Sand control and other flow control devices are installed at locations from which the formation fluid is extracted into the lateral wellbore. However, in open hole lateral wellbores, the junction between the main wellbore and the lateral wellbore includes no sand control devices that prevent the flow of particles, such as sand, from entering into the main wellbore from the lateral wellbore. Excessive sand production is detrimental to the equipment in the wellbores. This problem can be exacerbated when the open hole is formed in an unconsolidated formation, as such formations can produce excessive amounts of sand. 
     The disclosure herein provides wellbore systems that include sand control apparatus that inhibit or prevent flow of particles above a certain size from the junctions and the lateral wellbores into the main wellbore and methods of installing such apparatus. 
     SUMMARY 
     In one aspect, a wellbore system is disclosed that in one non-limiting embodiment includes a first wellbore capable of producing a fluid from a first formation, a second wellbore intersecting the first wellbore at a junction, wherein the second wellbore is an open hole and capable of producing a fluid from a second formation and a sand screen at the junction configured to inhibit particles larger than a selected size from flowing from the second wellbore and the juncture into the first wellbore. 
     In another aspect, a method of forming a wellbore is disclosed that in one non-limiting embodiment includes: forming a first wellbore capable of producing a fluid from a first formation; forming a second wellbore from a junction in the first wellbore; and placing a sand screen at or proximate to the junction to inhibit and/or prevent particles larger than a selected size from flowing from the second wellbore and the junction into the first wellbore. 
     Examples of the more important features of the apparatus and methods of the disclosure have been summarized rather broadly in order that the detailed description thereof that follows may be better understood, and in order that the contributions to the art may be appreciated. There are, of course, additional features that will be described hereinafter and which will form the subject of the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a detailed understanding of the apparatus and methods disclosed herein, reference should be made to the accompanying drawing and the detailed description thereof, wherein: 
       The FIGURE is a schematic diagram of a non-limiting production multilateral wellbore system showing a cased main wellbore an open hole lateral wellbore and a sand screen at the junction of the main wellbore and the lateral wellbore for preventing flow of particles above a selected size from the junction into the main wellbore, according to one embodiment of the disclosure. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     The FIGURE is a schematic diagram of a non-limiting production multilateral wellbore system  100  showing a main wellbore and a lateral wellbore with a screen at the junction of the main wellbore and the lateral wellbore for preventing flow of particles above a selected size from the junction, according to one embodiment of the disclosure. The system  100  is shown to include a main well or wellbore  110  formed in a formation  102  for producing fluid  118  from formation  102 . The main wellbore  110  is shown as a cased wellbore that may be lined with a casing  104 , which may be any suitable liner, including, but not limited to, a pipe made from joining pipe sections or another metallic liner. The wellbore  101  is shown to include cement  106  in the annulus  108  between the wellbore  110  and the casing  104 . The casing  104  is shown to include a window  120  through which a lateral wellbore  180  has been formed to a depth  182 . In the particular embodiment of the FIGURE, the lateral wellbore  180  is shown as an open hole, i.e., it is not lined with a casing, such as casing  104  in the main wellbore  110 . For the purpose of this disclosure an open hole is at least partially not lined with a casing or liner. The lateral wellbore  180  and the main wellbore  110  form a junction  130  at the window  120 . In the particular embodiment of system  100 , the junction  130  between the main wellbore  110  and the lateral wellbore  180  is not sealed and thus fluid  132  from the formation  102  can flow from the formation  102  into the main wellbore  110  via the junction  130  as shown by arrows  133 . For illustration purposes and not as a limitation, the wellbore system  100  is shown to include a single lateral wellbore  180 . It will be understood that there may be more than one lateral wellbore formed from the main wellbore and/or from one of or more lateral wellbores. Furthermore, for the purpose of this disclosure, any or all such lateral wellbores may be open hole or cased-hole wellbores. 
     The lateral wellbore  180  includes inflow devices, such as a sand screen  184  and other devices, such as flow control devices (valves, pressure drop devices, etc. known in the art), collectively referred to by numeral  186 . Fluid  188  from a production zone  190  may flow into the lateral wellbore  180  via devices  184  and  186 , as shown by arrows  188   a . The fluid  188  flows into the wellbore  180  and then into the main wellbore  110  at the junction  130 , as shown by arrows  188   b . As noted earlier, fluid  132  from the formation proximate the junction  130  also may flow into the main wellbore  110  as shown by arrows  133 . In one non-limiting embodiment, a lateral liner  140  (sometimes referred to in the industry as “lateral hook liner”) extends from a location  140   a  in the main wellbore  110  uphole (or above) of the junction  130  to a location  140   b  downhole (or below) of the junction  130  proximate to the screen  184  in the lateral well bore  180 . The lateral liner  140  includes a through passage  144  that provides a through opening in the main wellbore  110  across the junction  130 . The fluid  132  from the junction  130  flows or is directed to flow into the main wellbore  110  via fluid path  134  between the lateral liner  140  and the casing  104 . The fluid  188 , however, will generally flow into the main wellbore  110  from inside of the lateral liner  140 , as shown by arrows  188   b . Alternatively, the lateral liner may be located at any other suitable location in the wellbore system  100  so as to direct the fluid  132  from the junction toward the sand screen  160 . 
     Still referring to the FIGURE, the main wellbore  110  is shown to include a production string  112  having a production tubing  114  that includes a window or opening  150  that in one embodiment may extend across the window  120 , such as from a location  150   a  above the window  120  to a location  150   b  below the window  120 . Seals, such as packers  134   a  and  134   b  are respectively placed between the tubing  114  and the casing  104  above and below the window  120  to cause the fluid  188   b  to flow from the lateral wellbore  180  into the production tubing  114  and to cause fluid  132  to flow into the production tubing via fluid path  136 . 
     In one non-limiting embodiment, a flow control device, such as a sand screen  160  of sufficient length and size is placed in the production tubular  114  to inhibit or prevent flow of solid particles above a certain (selected) size in the fluid  132  and fluid  188   b  from entering the production tubing  114 . In one aspect, the sand screen  160  may extend from a location  160   a  above the junction  130  to a location  160   b  below the junction  130 . In one non-limiting embodiment, the sand screen  160  may be placed in a tubing  170  and placed inside the production tubing  114 . Alternatively, the sand screen  160  may be placed in the lateral wellbore  180  or partially in the main wellbore  101  and partially in the lateral wellbore  180 , each such screen adapted to or configured to inhibit or prevent solid particles above a size from entering the flow of the fluid toward the surface. In one non-limiting embodiment, the production tubing  114  includes an inward profile (also referred as indentations)  116  and the tubing  170  includes a collet  172  that is configured to engage with (mate with) the profile  116 , so that when the collet  172  engages with the profile  116 , the tubing  170  will securely hang inside the production tubing  114 . In one embodiment, the tubing  170  also included another profile  176 . To install or place the screen  160  in front of the junction  130 , collet  175   a  on a run-in tool  175  is engaged with the profile  176  on the tubing  170  at the surface. The run-in tool  175  carrying the tubing  170  and the sand screen  160  is moved into the production tubing  114  until the collet  172  engages with the profile  116 . In aspects, the force (pull force) required to dislodge the collet  172  from the profile  116  is greater than the pull force required to dislodge the collet  175   a  from the profile  176  and thus the run-in tool  175  from the profile  116 . Once the tubing  170  has been placed in the production tubing  114 , the run-in tool  175  is pulled out of the tubing  114 , leaving the sand screen  160  in front of the junction  130 . Seals  162   a  and  162   b  are provided between the tubing  170  and the production tubing  114  to prevent flow of the fluid from the lateral wellbore  180  or the junction  130  to bypass the sand screen  160 . In other aspects, devices in addition to the sand screen may also be placed outside the screen ( 198 ) r inside the screen ( 189 ). For example, a flow control device, such as sliding sleeve valve, may be placed inside the sand screen  160  to control the flow of the fluid from the lateral wellbore  180 . In another aspect, a flow control device that discriminates flow of one type of fluid against another type of fluid may be placed inside the sand screen  160 . Such devices are known in the art and may include, but are not limited to, device having a tortuous fluid flow path; a device that inhibits flow of water compared to the flow of oil or gas; and a flow that created a greater pressure drop for water compared to oil or gas. Also, the sand screen may be any suitable sand screen. 
     The foregoing disclosure is directed to certain exemplary embodiments and methods. Various modifications will be apparent to those skilled in the art. It is intended that all such modifications within the scope of the appended claims be embraced by the foregoing disclosure. The words “comprising” and “comprises” as used in the claims are to be interpreted to mean “including but not limited to”. Also, the abstract is not to be used to limit the scope of the claims.