Patent Publication Number: US-6209644-B1

Title: Assembly and method for forming a seal in a junction of a multilateral well bore

Description:
FIELD OF INVENTION 
     This invention relates to an assembly and method to be used in the formation of seals at the junction of lateral wells drilled through windows in a main well bore casing or through any tubular type materials. Specifically this invention relates to novel and improved assemblies and methods used for forming seals in any deviated well bore which is drilled off or from another well bore whether it is vertical, deviated or horizontal and whether it is the primary well bore casing or other tubular material. More specifically this invention relates to the completion procedures used in completion of wells with deviated well bores off a main or casing well bore where as part of the completion procedure the well may be cemented and sealed. 
     BACKGROUND OF THE INVENTION 
     The drilling and completion of horizontal wells in recent years has offered dramatic improvements in the production of hydrocarbons and their recovery from the formations in which they are found. Although horizontal wells have been known for many years, it has only been in the last decade that this technology has been accepted by the industry and used as a proven and cost effective means to increase production and maximize ultimate recovery of hydrocarbons from a reservoir formation while lowering the cost to do so. As the industry has come to realize, horizontal wells frequently improve production by factors of 5 to 10 time in suitable reservoirs, such as for example those which are located in naturally fractured areas or are in heavy oil application zones. 
     Because of the improved economics in both the cost of production and the ultimate recovery of hydrocarbons reserves associated with horizontal drilling generally, many areas of the world have adopted such drilling techniques over the older technique of just drilling vertical wells. As horizontal and multilateral wells generally minimize the number of well locations and infrastructure required to develop an oil and gas field, this technique has become 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 for drilling which have adopted the use of laterals or multilateral which are particularly useful for horizontal development include reservoirs in urban areas, wildlife preserves, and permanent frost zones. 
     Multilateral wells are becoming increasingly important both from the standpoint of drilling a new well or for reworking an existing well to improve productivity and maximize the recovery of hydrocarbon reserves in place. Thus the use of multilateral wells have been accepted in reservoirs were horizontal drilling allows optimization of hydrocarbon recovery as for example in water drive systems which allow water injection efficiency to be increased and in the development of thin, or stacked reservoirs which would otherwise require many vertical wells, and in well as reservoirs with coning problems where by using horizontal drilling allows laterals to be optimally spaced for the fluid contact. 
     The incentives of cost effectiveness and environmental soundness, have expanded the use of multilateral or horizontal wells to be used in both the development of new wells and for re-entry of existing wells in established fields for stimulation and workover activities. Further the industry in its search for the most cost effective means to produce hydrocarbons with the least environmental impact has turned to multilateral and horizontal wells in great numbers. 
     The reasons are simple, as to why the industry has turned to multilateral wells, because in using multilateral wells drilled off a single main well bore, only one single main well bore is needed to be drilled and the additional recovery from the well is achieved by drilling laterals from the one single main well bore. However as the industry has placed ever increasing dependence on S 0  multilateral well completion, there has been greater demand within the industry for advancing the technical capabilities of the multilateral technology. For example in completions systems and technology for the installation of lateral junctions in certain formations which are well known, there has been a primary barrier to the increased use of multilateral technology. This barrier has been the limitations in the completion options available, particularly in those situations in which a sealed junction is required to effectively produce a reservoir. Situations, such as those in which a hydraulically sealed lateral junction are desired, 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 formations fluids into the primary casing is unacceptable. These are just some of the situations which the current technology has not been able to over come on a consistent basis, except with the most expensive technologies in use today. 
     Further the technology which has only recently become available for the formation of junctions with hydraulic integrity is often too expensive to allow its utilization in all but the large budget wells, such as those found in offshore locations. At the present time, this sealed completion technology is generally not accepted as reliable by the industry for the average budget well. This has resulted in potentially high economic risk to install such systems. In addition, these completion systems may not allow the capability to selectively re-enter these laterals at a future time, nor to pressure test the junction for hydraulic integrity prior to the removal of the installation tools. 
     The prior art until the mid-1990&#39;s did not typically have a liner laid in a lateral and therefore these laterals were not tied back to the main well bore which severely limited or made impossible the re-entry of these laterals when workovers or cleanouts were required. However, subsequently, it became increasingly popular to case the laterals, as well as to tie back these laterals to the main well bore, but this tie back technology though making it easier to re-enter the well did not allow the junction to be hydraulically sealed to a significant pressure, such as 1,000 psi or more. 
     Also in the prior art where some sealing was able to be obtained it usually required multiple trips to install and perfect the seal, often 3 or more. This resulted in great expense in rig and personnel time, particularly in those high cost locations, such as offshore areas, which meant that many wells could not afford the technology and thus those wells could not receive the benefit of the multilateral technology. 
     Moreover, these earlier prior art systems did not allow the hydraulic integrity of the completed junction to be tested, and/or possibly repaired, prior to removing the tools used to install the seal. This was especially important in the high cost locations because of the excess expense in remobilization of the rig equipment and personnel for re-tripping back into the hole to bring the seal up to the design criteria determined necessary. 
     The prior art in many cases had to leave a packer in the main well bore in order to even attempt the re-entry back into the lateral well bore, which thus placed an obstruction or limit on the access to the main well bore below the packer. This forced well operators to have to make an election of which way they wanted to go and limited the number of lateral which could be drilled off on main well bore, if they elected to leave the packer in place in the main well bore. 
     Further, the prior art is legion with patents attempting to solve the problems of providing a reliable completion of a multilateral well such as U.S. Pat. No. 2,397,070 which describes a lateral well bore completion using flexible casing together with a movable gate for closing off the lateral. Of a similar nature is U.S. Pat. No. 2,797,893, which discloses a method for completing lateral wells using a flexible liner and a deflecting tool. 
     Several other prior patents such as U.S. Pat. No. 5,318,122 attempted to accomplish seals using a deformable device that selectively seals the juncture between the vertical and lateral wells using an inflatable mold which utilized a hardenable liquid to form a seal in conjunction with an expandable memory metal device or other devices for plastically deforming a sealing material to form a seal. 
     Such patents as U.S. Pat. No. 5,787,987 attempted to form a seal in the joint between the window in the well bore casing and the tubing being run into the lateral, by attempting to use the inside surface of the well bore casing as the sealing surface in conjunction with the flange being put into the well to seat with it. The sealing surface about the well bore casing does not provide as high of quality seal because of the material of the well bore casing not being a material which has been prepared for the purpose of forming a seal. Once in place then another run would be made into the well to put in place a sleeve to wedge the flange against the inside wall of the well bore about the window to form the seal. In this patent the old problem of multiple runs into a well to achieve a seal in the window section again shows up. 
     Further such art of a general nature including U.S. Pat. Nos. 2,452,920, 4,402,552, 5,289,876, 5,301,760, and U.S. Pat. No. 5,474,131 provided yet more examples of the teaching of the prior art which attempted to solve the problems in this art without the results which are achieved by the invention of this patent. 
     OBJECTS OF THE INVENTION 
     This invention is most broadly related to an assembly and method for forming a seal at the junction of a lateral well bore drilled through a window in a main well bore casing, or any other tubular material which has a window section formed therein such that a hydraulic seal is formed between the junction of the vertical and lateral well, and further that a sealed isolation zone is created between the respective lateral wells in a multilateral well system. 
     More specifically this invention comprises a tubular member for being run into the well bore casing or other tubular material, having at least one orientation member for orientation of the tubular member in the main well bore casing, with the tubular sleeve member having an aperture through it for being run into the well bore casing for alignment of its aperture with the window in the well bore casing. Further this assembly has a seating surface on the inside of the tubular sleeve member proximate the aperture. Also a sealing member is positioned about the tubular member for seating with the seating surface inside the tubular sleeve means proximate the aperture in the tubular sleeve member and for forming a seal when brought into engagement with the sealing member as the tubular means is run into the well bore and the lateral well bore. A deflection member positioned and releasably sealed in the tubular sleeve for deflecting the tubular means through the window, and functionally connected to the at least one orientation member for orientation of the deflection member relative to said window in the well bore casing for defecting the tubular means through the window and for aligning the aperture through the one side of the tubular sleeve member with the window in the main well bore casing. In further aspects of this invention the object of providing an assembly and method for providing the ability to re-enter the lateral wells would be provided, and the capability to pressure test, and repair, if necessary the junction for hydraulic integrity prior to the removal of the installation tools from the well would be provided, the capability to perform the afore mentioned in a single drill pipe trip in order to reduce the cost of such sealed lateral completions to make the use of this technology economical for lower producing wells, and the capability to install the completion assembly in a single trip into the well bore would be achieved. 
     It is the object of this invention to over come some of the deficiencies, drawbacks and shortcomings in the prior art which are discussed above by the usage of the assembly and methods of the invention disclosed herein. 
     In that regard it is an object of this invention to provide the assembly and methods to form and establish hydraulic integrity of a junction at a window downhole between a main casing and a lateral well bore for the purpose of preventing fluids from migrating into or out of the casing through this junction. 
     It is a further object of this invention to provide the apparatus and methods to establish hydraulic integrity of the junction between a main casing or other tubular material and the lateral which is relatively simple and inexpensive to install which makes it suitable for use in moderate producing wells, which generally have smaller budgets. 
     Also it is an object of this invention to provide control orifices which can be used to selectively re-enter the lateral at a future time without the need for a packer device or other orientation members being required to remain in the main well bore as an obstruction in the main well bore after the sealing means is installed in the junction. 
     Yet another object of this invention is to provide a tight pressure seal above and below the window in the main casing, as well as a tight hydraulic seal all around the window in order to prevent the migration of fluids either into or out of the main well bore casing or tubular member, which in some cases would be a lateral well liner. 
     A further object of this invention is to generally use a compression seal member to achieve the tight pressure seal above and below the window opening in the main well bore casing, as well as the tight hydraulic seal all around the window opening to prevent the migration of fluids either into or out of the main well bore casing or tubular member, which in some cases would be a lateral well liner. 
     Also a further object of this invention is to provide a compression sealing member for creation of a seal between the tubular sleeve member in the main well bore casing and the tubular member, or production liner in some cases, in order to prevent the migration of fluids either into or out of the main well bore casing or tubular member. 
     Yet a further object of this invention is to provide a compression sealing member for receiving sufficient fluid to expand the compression sealing member to create a seal between the compression sealing member and the tubular sleeve member in the main well bore casing in order to prevent the migration of fluids wither into or out of the main well bore casing or tubular member, which may be a production liner. 
     A further object of this invention is to provide a sealing member for seating with the a seating surface inside the tubular sleeve member proximate the aperture through the one side of the tubular sleeve member, and moved into engagement with the seating surface for preventing the migration of fluids either into or out of the main casing or production liner. 
     Also an object of this invention is to provide a method to pressure test the multilateral junction subsequent to the installation of the sealed completion but prior to the removal of the tubular member running tool from the well bore, and thus allow a great cost savings compared to re-mobilizing the rig and operating personnel if it is discovered at a future time that the required pressure integrity does not exist. 
     Yet a further object of this invention is to provide a means to repair the seal created in the junction, if necessary, prior to the removal of the tubular member running tool from the main casing well bore, and thus realize a great cost savings as opposed to re-mobilizing a rig and operating personnel if it is found that the required pressure integrity was not obtained. 
     Also an object of this invention is to provide a deflection member with in the tubular sleeve member which deflects the tubular member or production liner through the window and into the lateral without the requirement for a separate drill pipe trip to install the deflector member. 
     A further object of this invention is to provide a deflection member which is positioned and releasable sealed inside the tubular sleeve member which provides hydraulic integrity prior to the establishment of the seal at the junction but when removed leaves the tubular sleeve member substantially open for access down the main well bore casing. 
     Yet another object of this invention is to provide at least one orientation member for orientation of said deflector member and for aligning the aperture through the tubular sleeve with the window and for operating in conjunction with the deflector member and tubular sleeve both of being set in the main well bore casing and in the removal from the main well bore casing to leave a clear well bore, which is unrestricted. 
     Also an object of this invention is to provide an orientation member, having spring loaded key located on the tubular sleeve member which pop open into a key way located in the main casing window to allow the tubular sleeve member be aligned with the window and to align the aperture through the one side of the tubular sleeve member with the window by following the window sill as it moves downward until it is properly aligned, thus eliminating the need for a packer device or other obstruction to remain in the main well casing bore that would restrict or prohibit access to the well bore below the obstruction. 
     Yet a further object of this invention to use the one orientation means for orientation of the deflection member to also actuate slip devices which provide a means to hold the tubular sleeve member in a set and fixed position and to also set a seal between the main well bore casing and the tubular sleeve member to seal the main well bore casing below the seal member when the orientation member has been fully oriented and set. 
     Also an object of the invention is to allow the deflector member located within the sleeve device to be recovered with a single trip of the drill string or wire line after the installation of the sealed multilateral junction is completed. 
     A yet further object of this invention is to provide an assemblies and methods to establish hydraulic integrity at the junction of a multilateral well bore in a single trip of the drill string, while greatly reducing the cost of this installation due to the saving in rig time. 
     Yet further and additional benefits and improvements or the invention will be appreciated by other skilled in the art and those advantages and benefits of the invention will become apparent to those skilled in the art upon a reading and understanding of the following detailed description and drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1A is a side elevation view in partial cross section of the assembly of this invention for forming a seal at the junction of a lateral well bore drilled through a window in the main well bore casing as the assembly is being lowered down hole pasted the window with the key member popped outward into the window opening. 
     FIG. 1B is side elevation view in partial cross section of the assembly of this invention for forming a seal at the junction of a lateral well bore drilled through a window in the main well bore casing as the assembly has come to rest on the window sill with the key member popped outward into the window opening and coming to rest on the window sill. 
     FIG. 2A is a front elevation view of main well bore casing having a window there in and through which a lateral well bore would have been drilled and in this embodiment an orientation key way is provided at the down hole end of the window sill for receiving a key member but as shown here no key member has reached the window and all that is showing is the window section in the well bore. 
     FIG. 2B is a representational front elevation view of a main well bore casing having a pre-cut window there through and showing a pre-cut key way in the window and the key member has popped outward into the window and is moving downward with rest of the assembly (not shown here) to find the key way for orientation of the rest of the assembly of this invention. 
     FIG. 2C is a representational front elevation view of a main well bore casing which is the natural result of down hole milling the window in the casing while down hole and the key member has popped outward into the window and is moving downward with the rest of the assembly (not shown) to land on the window sill of the window for orientation of the assembly. 
     FIG. 2D is a representational front elevation view of a main well bore casing which has a down hole milled key way milled in the window of the casing and the key member is being guided by the window sill to orient the assembly (not shown) of this invention and bring the key member to rest in the down hole milled key way. 
     FIG. 2E is a representational front elevation view of a main well bore casing which has a down hole milled key way milled in the window of the casing and the key member is being actively guided by the window sill to orient the assembly (not shown) of this invention in the process of bring the key member to rest in the down hole milled key way. 
     FIG. 2F is a representational front elevation view of a main well bore casing which has a down hole milled key way milled in the window of the casing and the key member has been guided by the window sill to orient the assembly (not shown ) of this invention and the key member is at rest and secured in the down hole milled key way. 
     FIG. 3A is a side elevation view in partial cross section of the key member as it is mounted in the deflector member and showing the key member just as the tubular sleeve member having an aperture through one side is aligned with the window in the well bore casing. 
     FIG. 3B is a side elevation view in partial cross section of the key member as it is mounted in the deflector member and showing the key member with additional pressure having been applied to the deflector member to overcome the spring in the key member for driving the deflector member downward while the key member is stopped in the key way, and thereby forces the setting of the seal member and slip grabbing members to secure the tubular sleeve member and deflector member in a sealed and fixed position in the main well bore casing. 
     FIG. 4 Is a front elevation of the deflector member of this invention out of the tubular sleeve member of the assembly of this invention. 
     FIG. 5A is a side elevation view of the assembly of this invention in partial cross section which shows the deflector member positioned and releasable seated in the tubular sleeve member and the deflection member and key member having set the seal member to form a seal down hole in the main well bore casing between the main well bore and the tubular sleeve member and having set the slip grabbing means to prevent movement of the tubular sleeve member and the tubular member has been functionally separated from the deflector member and deflected and landed into the lateral well bore. Further the orientation key member is at position A—A in the muleshoe key way and the lower part of the aperture is at A′—A′ but prior to any controllable collapsing of the upper part of the tubular sleeve member in communication with the aperture. 
     FIG. 5B is a side elevation view of the assembly of this invention in partial cross section which shows the orientation key member for orientation of the tubular member seated in the key way of the mule shoe and the tubular sleeve member having been driven downward to set the up hole seal between the main well bore casing and the tubular sleeve member and having moved to a stopped position. Further the orientation key member is now shown at position B—B in the muleshoe keyway and has controllably collapsed the upper part of the tubular sleeve member in communication with the aperture and has moved the lower part of upper part of the tubular sleeve member in communication with the aperture to B′—B′ and the sealing member positioned about the tubular member for seating with the seating surface inside the tubular sleeve member proximate the aperture is being moved into place. 
     FIG. 5C is a side elevation view of the assembly of this invention in partial cross section which shows the orientation key member for orientation of the tubular member and the key member seated in the key way of the mule shoe with the tubular sleeve member driven downward to a stopped position C—C and the tubular member released from the orientation key member to move further downward to finally seat the sealing member against the seating surface inside the tubular sleeve member proximate the aperture through the tubular sleeve member at C′C′. 
     FIG. 6 is a partial cross section front view of the tubular sleeve member with the controllably collapsible upper part in view and uncollapsed. 
     FIG. 7A is a front elevation view of the tubular sleeve member with the orientation member for the tubular member and key in phantom view at a first position prior to the controlled compression of the upper tubular sleeve member but with the seal on the down hole end formed and slip grabbing members set. 
     FIG. 7B is a front elevation view of the tubular sleeve member with the orientation member for the tubular and key in phantom view at a second position after the controlled Compression of the upper tubular sleeve member and with the upper seal set. 
     FIG. 8 is a partial cross section of the tubular sleeve member, the tubular member, the sealing means positioned about the tubular member and seated with the surface inside the tubular sleeve member proximate the aperture and showing an elastic tubular seal member and a one way check valve to inflate the elastic tubular seal member. 
     FIG. 9 is a partial cross section of the seal at the junction formed in a lateral well bore and the assembly of this invention being used to pressure check the seal before leaving the well and pulling the equipment from the well. 
     FIG. 10 is a partial cross section the tubular sleeve member and deflector member in place in the well and the tubular member and sealing member positioned about the tubular member for seating being run on a different trip into the well to form a seal a the junction of the lateral well bore drilled through the window in the main well bore casing. 
     FIG. 11 is a partial cross section of the deflector member being pulled from the tubular sleeve member after the seal at the junction of the lateral well bore drilled through the window in the main well bore casing has been formed and showing that the main well bore casing will be substantially clear after the seal at the junction was formed. 
     FIG. 12 is a partial cross section of the main well bore casing with the seal at the junction of the lateral well bore drilled through the window in the main well bore casing has been formed and showing that the main well bore casing is substantially clear after the seal at the junction was formed. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring now to FIG. 1A wherein a representational main well bore is generally shown as with a main well bore casing shown at  11 , it should be understood all through out the teachings of this invention that while the drawings and discussion about the preferred embodiments may refer to vertical for the main well bore  10  or main well bore casing  11 , they, in fact, may be in a vertical position, or deviated therefrom, or a horizontal position, without departing from the teachings of this invention. Further it should be understood that the references to up hole and down hole as shown in the drawings and discussions about the preferred embodiment, may, in fact, in the ground be horizontal on occasions or even have up hole and down hole reversed, but the general teaching is that up hole mean back toward the surface of the ground and downhole means into the hole in the opposite direction from up hole whether it is down hole or not in the well. Similarly the term lateral well bore or a multilateral well bore may or may not be truly lateral or horizontal but may be just more deviated than the main well bore  10  from which it is “kicked off from” but it will be generally referred to as a lateral well bore  12  or a multilateral in the teaching of this invention never the less. 
     It should also be understood that while the preferred embodiments shown make reference to main well bore and main well bore casing, in fact any tubular product from which a lateral or multilateral drilling of a bore could be achieved could be used in the practice of this invention. Thus it could be used in the well bore of a lateral to drill another lateral well without deviating from the teachings of this invention. It could be used with coiled tubing to drill a lateral well from the coiled tubing which might be the equivalent of the main well bore casing or it may be a lateral well from which an additional lateral might be drilled without departing from the teachings of this invention. 
     Referring more specifically to FIG. 1A, the assembly for forming a seal at the junction of a lateral well bore  12  drilled through a window  13  is generally shown as  14 . In this particular FIG. 1A the assembly  14  is shown being lowered down hole in the main well bore casing  11 , which has the window  13  in a section of the casing already in place in the main well bore casing  11 . It should be understood that this window  13  could have been added to the make up of the casing string or it could have been milled down hole in place, either of which would not effect the practice of this invention, which makes this invention have universal application. 
     As can be seen in FIG. 1A this assembly  14 , at least in this embodiment, comprises generally a tubular sleeve member  15  with a releasablely sealed deflection member  16 , sometimes referred to as a “Whip Stock”, positioned in the tubular sleeve member  15 . The tubular sleeve member  15  is provided with an aperture  21 , as best seen in FIGS. 6,  7 A, and  7 B, through at least one side of the tubular sleeve member  15  which can be brought into alignment with the window  13  when the tubular sleeve member  15  is run into the main well bore casing  11  and has a seating surface  17 , shown in FIGS. 5A,  5 B, &amp;  5 C, and  8  inside the tubular sleeve member  15  which is proximate the aperture  21 . The deflection member  16  has an outwardly biased key  18  which when being run in is the main well bore casing  11  is compressed back into the deflection member  16  through a key hole  19  in the tubular sleeve member  15 . When however, because the assembly  14  is rotated in the main well bore casing  11  as it is let down hole, the outward biased key  18  arrives at the window  13  in the main well bore casing  11 , the key  18  will pop outwardly into the window  13  and catch on the sill  20  of the window  13 . This catching on the sill  20  of the window  13  by key  18  provides an operator on the surface with the knowledge that the assembly  14  has found the window  13  and will be properly oriented once the operator just lowers the assembly  14  straight down hole, because the outwardly biased key  18  which popped outwardly into the window  13  will follow the window sill  20  of the window  13 , as best seen in FIGS. 2A thru  2 F, to the down hole end  52  of the window  13  or into a window key way  26  into proper orientation for alignment and positioning the aperture  21  with the window  13  of the main well bore casing  11 . Also shown in FIGS. 1A and 1B, and additionally in FIGS. 6,  7 A and  7 B the tubular sleeve member  15  has on it&#39;s up hole end a tubular mule shoe  22  which will provide mechanical guidance into a mule shoe key way  23  which is also formed in the up hole end of the tubular sleeve member  15  for orientation of yet another part of the assembly  14  of this invention, which will be further explained later. 
     In at least the embodiment shown in FIGS. 1A and 1B, the tubular sleeve member  15  is releasablely and functionally connected to a tubular member  24  through intermediated parts but still remains part of the assembly  14 . For example the functional connection may be through intermediated parts such as by connecting the tubular member  24  to, for example, a well liner  55  which is connected to the deflection member  16  which is in turn connected to the tubular sleeve member  15  and still be part of the assembly  14  which can then, as in this embodiment, be used to run both the tubular sleeve member  15 , deflection member  16 , tubular member  24 , and the well liner  55  into the main well bore casing  11  and the lateral well bore  12  with only one trip into the well, while setting the intermediate parts and forming a seal. When this embodiment or any other is used the tubular member  24  is part of the assembly  14  and it has a sealing member  25  positioned about the tubular member  24  and an orientation key  40  for orientation of the tubular member  24  and the sealing member  25  relative to the aperture  21  of the tubular sleeve member  15  to bring the sealing member  25  into engagement with the seating surface  17  inside the tubular sleeve member  15  proximate the aperture  21  as the tubular member  24  is run into the lateral well bore  12  and the main well bore casing  11 . It will be understood by those skilled in the art that a drill string  53  might be connected to a “Stab-in”  54 , which may be a modified drill string section, which is connected to the tubular member  24  and which in turn might be connected to a lateral liner  55  for example or a wire is screen or other tubular material or intermediate material for placement in the lateral well bore  12  and then used to position the tubular sleeve member  15  and deflector member  16  with the window  13  and also run the tubular member  24  with the sealing member  25  positioned about the tubular member  24  into place on one trip into the well. Further those skilled in the art would also understand that a drill string  53  may be used to position the tubular sleeve member  15  and deflector member  16  with the window  13  and then run the tubular member  24  with the sealing member  25  positioned about the tubular member  24  at a later time without departing from the teaching of this invention. However when the tubular member  24  is run with the tubular sleeve member  15  the complete installation of assembly  14  can be completed for achieving a seal at the junction of a lateral well bore  12  and a main well bore casing  11  in a single trip into the well, which as those skilled in the art will appreciate is desirable. 
     By referring to FIGS. 2A through 2F it can be better understood how key  18  is used with the window  13  and sill  20  of the window  13  to align and position the tubular sleeve member  15  with it&#39;s aperture  21  in position with the window  13 . As those skilled in the art will appreciate there are many kinds of windows which can be used by the industry in the multilateral or lateral drilling process and the assembly  14  of this invention can be used with almost all of them to practice the teaching of this invention for forming a seal at the junction of the lateral well bore  12  with the main well bore casing  11 . Thus this assembly  14  and the method of it&#39;s practice have universal application in the lateral and multilateral well arts with all types of windows. 
     For example referring to FIG. 2A a window  13  is shown formed in the main well bore casing  11  with a window key way  26  provided at the down hole end or sill  52  of the window  13  and located in the main well bore  10 . As shown in this FIG. 2A view the assembly  14  has not yet arrived at the window  13  because the window is clear. However by referring to the representational FIG. 2E it can be seen the assembly  14  of this invention has arrived at the window  13  and the key  18  which is connected to the assembly  14  has popped outwardly into the window  13  and is being lowered by the operator down hole. It can be seen in FIG. 2D that the sill  20  of the window  13  is guiding the key  18  and the assembly  14  into correct orientation and position as the whole assembly  14  is being lowered down hole by the operator from above. The key  18  will be in position when it reaches the down hole sill  52  at the down hole end of the window  13 . 
     Referring to FIG. 2F, it can be seen that the key  18  has finally come to rest in the key way  26 , when the window  13  has a key way  26 , which will positively position and align the aperture  21  of the tubular sleeve member  15  and the deflector member  16  with the window  13  of the main well bore casing  11  for the practice of this invention in forming a seal at the junction of the lateral well bore  12  in the main well bore casing  11 . 
     Referring to FIG. 2B as a further example, it can be seen that in a pre-cut window  13 , which would have been added to the main well bore casing  11  as part of making up the main well bore casing  11 , provides a window  13  and sill  20  with a key way  26  at the down hole sill  52  also for the practice of this invention using the assembly  14 . In FIG. 2B however as shown, the key  18  is not quiet in position in the key way  26  and thus the positioning and alignment of the assembly  14  has not been achieved yet, but is in process. 
     Referring to FIG. 2C, by way of explanation, it can be seen that a window  13  and sill  20  have been formed by a down hole milling operation and the window  13  and the sill  20  which are formed are just the natural result of the target configuration produced by the milling bit which would have been used to mill them in the down hole milling process. This natural result however allows the use of the assembly  14  of this invention to form a seal at the junction of the lateral well bore  12  and the main well bore casing  11  in the same manner as with the premilled windows  13 . 
     In some down hole milled window art, the art has perfected ways to also mill key ways down hole to achieve better alignment and positioning of tools for multilateral operations. For example in FIG. 2D, it can be seen that in a down hole milled window  13  and down hole milled key way  26  the assembly  14  of this invention is still useful. In the FIG. 2D shown, the key  18  has popped outwardly into the window  13  and has engaged the sill  20  of this window  13  which will give the operator on the surface an indication that the assembly  14  has reached the window  13 . The operator then would just let down on the drill sting, on which this assembly  14  might be run, to allow the sill  20  of the window  13  to guide the key  18  into the key way  26  for bring the assembly  14  of this invention into alignment with the window  13 . Once again the assembly  14  of this invention can be used with yet another type of window  13  and key way  26  found in the industry to achieve the results of this invention. 
     By now referring to FIG.  1 A and FIG. 1B it will be seen that in FIG. 1A that the assembly  14  with the key  18  popped outwardly through the key hole  19  into the window  13  has, thus, found the window  13  and is being lowered down hole toward the key way  26  but has not yet come to rest in the key way  26 , and is at a position A—A as shown, while in FIG. 1B the key  18  has come to rest in the key way  26 , and is at a position B—B as shown. In this embodiment the tubular member  24  is being used in conjunction with a drill string  53 , not shown in these figures, and a “Stab In”  54  connected at a drill collar  62 , not shown in these figures, to run the tubular sleeve member  15  into the main well bore casing  11  and into alignment with the window  13 . However the tubular member  24  and tubular sleeve member  15  may be run on any running device capable of running tools into the main well bore casing  11 . It should be noted that in other embodiments that the tubular sleeve member  15  may be set first and then the tubular member  24  might be run into the main well bore casing  11  and lateral well bore  12  at a later time without departing from this invention. 
     Referring to FIG. 1A, which is the running position of the assembly  14 , it can be seen, in this embodiment, that the deflector member  16  is positioned in the tubular sleeve member  15  and releasable and slidably sealed therein by an o-ring seal  27  which thus seals the tubular sleeve member  15  from fluid flow there through once the tubular sleeve member  15  is set in the main well bore casing  11 . Also, as best seen in FIGS. 3A and 3B, packer seal  28  is mounted on and through the tubular sleeve member  15  for being driven outwardly to form a seal between the main well bore casing  11  and the tubular sleeve member  15 . Further mounted down hole on tubular sleeve member  15  are slip grabbing members  30 , which are mounted for being driven outwardly into the main well bore casing  11  to grip the main well bore casing  11  for setting the tubular sleeve member  15  to prevent the movement of the tubular sleeve member  15 . It should be understood by referring to the FIGS. 3A &amp; 3B that once the key  18  comes to rest in the key way  26 , then because the key  18  is passed through the key hole  19  of the tubular sleeve member  15 , the tubular sleeve member  15  comes to a stop. Also coming to a stop are the parts mounted therein, such as the packer seal  28 , slip grabbing members  30 , and key  18 . When the tubular sleeve member  15  come to a stop in the main well bore casing  11 , the aperture  21  is aligned with the window  13 . The deflector member  16 , however, while being releasable and slidably sealed in the tubualr sleeve member  15  would continue downward in response to the well operator continuing to let the drill string  53  down hole. 
     The key  18  is mounted into the deflector member  16  in a spring receiving box  31 , which has a first key spring  32  therein for compression by the key  18  when the assembly  14  is being run into the main well bore casing  11  but which is outwardly biased against the key  18  for popping the key  18  through the key hole  19  into the window  13  as has already been discussed. However, also mounted in the spring receiving box  29  is a second key spring  33  for keeping the key  18  in a downward position until the key  18  comes to a stop when the key  18  comes to rest on the downhole sill  52  or key way  26  of the window  13 , but will then compress and allow the deflector member  16  to continue downward motion while the key  18  remains in the stopped position. As the key  18  previously discussed is stopped the tubular sleeve member  15  with the packer seal  28 , and the slip grabbing members  30  are also stopped, but the releasable and slidable sealed deflector member  16  continues downward and drives against the packer seal  28  with a 1st cam surface  29  located proximate the packer seal  28  to press the packer seal  28  into sealing engagement with the main well bore casing  11 . Also on the down hole end of deflectoin member  16  is a 2nd cam surface  67  which is located proximate the slip grabbing members  30  for driving the slip grabbing members  30  outwardly into the main well bore casing  11  to grip the main well bore casing  11  for setting the tubular sleeve member  15  to prevent the movement of the tubular sleeve member  15  This configuration at least in this one embodiment, thus allows for the sealing and fixedly setting of the tubular sleeve member  15  in the main well bore casing  11  with the aperture  21  of the tubular sleeve member  15  and the window  13  aligned for further operations which will be discussed. 
     It should be noted that the deflector member  16  has an inclined upper surface  34  for deflecting the tubular member  24  or any other tubular good, such as liner  55 , through the window  13  when the tubular member  24  is run into contact with the inclined upper surface  34  of the deflection member  16 . Also located on the up hole end of the deflector member  16 , as best seen in FIG. 4, is provided a female retrieving member  35  which will be more fully explained later but is for the purpose of pulling the deflection member  16  out of the tubular sleeve member  15  after the seal has been formed in the lateral well bore  12  and the main well bore casing  11 . Further in some embodiments of the deflector member  16 , attachment points  36  are provided along this inclined upper surface  34 . 
     Also in some embodiments where the assembly  14  of this invention is to be run as a unitized assembly, the deflector member  16  has attaching points  36  which are provided on the deflector member  16  for allowing the attachment of a controlled releasable connector member  37 , as for example shear pins, for joining the deflector member  16  releasablely and functionally to the tubular member  24  whether directly or functionally, for example through a lateral liner  55  for running the assembly  14  into the main well bore casing  11 . In this configuration the controlled releasable connector member  37  allows the controlled release of the controlled releasable connector member is  37  after the deflector member  16  is stopped from down ward motion. The deflector member  16  is stopped when it has moved down hole the distance allowed by the second key spring  33  and spring receiving box  31 . Once the deflector member  16  can no longer be moved down hole, then the controlled releasable connector member  37  are released at the attaching point  36  such that the tubular member  24  and the lateral liner  55 , for example, may continue down ward motion. Thus the tubular member  24  with the sealing member  25  position about the tubular member  24  can continue to be lowered down hole for the formation of a seal at the junction of the lateral well bore  12  and the main well bore casing  11  at the window  13 , after the tubular sleeve member  15  and deflector member  16  are fully set in place in the main well bore casing  11 . It should also be understood that the tubular sleeve member  15  could be set first and then the tubular member  24  could be run at a later time without departing from the teachings of this invention. Also between the attaching point  36  and the tubular member  24  may be connected other tubular goods, which would be intermediate thereto, for insertion into the lateral well bore  12  and which also provide a functional connection of the tubular member  24  and the deflector  16 . 
     As the Tubular member  24  with the sealing member  25  positioned thereabout, continues down ward motion, an orientation key  40  releasablely connected to the stab in  54  by shear pins  56  at a predetermined distance from the sealing member  25  comes into engagement with the tubular mule shoe  22 , located on the up hole end of the tubular sleeve member  15  and provides mechanical guidance of the orientation key  40  to the mule shoe key way  23  for orientation of tubular member  24  and the sealing member  25  positioned thereabout. Once the orientation key  40  is stopped in the mule shoe key way  23  in the proper orientation, continued down hole pressure is applied to the tubular member  24  and the orientation key  40  shears shear pins  56  and releases the stab in  54  and tubular member  24  for a final push to put the sealing member  25  into place against the seating surface  17  inside the tubular sleeve member  15  proximate the aperture  21  and puts the tubular member  24  and the stab in  54  into the lateral well bore  12 . It would be understood by those skilled in the art that a lateral liner, lateral screen, or any other tubular goods could be used in place of the stab in  54  or with the stab in  54  to put them into the lateral well bore  12  in this manner and still form the seal of this invention. 
     In yet other embodiments of the assembly  14 , the tubular sleeve member  15  is formed in two pieces with the upper part, generally referred to at  41 , of the tubular sleeve member  15  being for controlled collapse and for sealing the tubular sleeve member  15  against the main well bore casing  11  proximate the upper part  41  of the tubular sleeve member  15  and for downward adjustment of the upper part, generally referred to at  42 , of the aperture  21  in the tubular sleeve member  15  by bringing the seating surface  17  located on the upper part  42  of the aperture  21  inside the tubular sleeve member  15  proximate the aperture  21  into a preferred configuration for mating with the sealing member  25  positioned about the tubular member  24  for seating. 
     Yet in other embodiments of the assembly  14  the tubular sleeve member  15 , as set out above, may be formed in two pieces which are respectively the upper part  41  and lower part  69 . The upper part  41  of the tubular member  15  being formed into a tubular insert  43  for insertion into the lower part  69  of the tubular member  15  as shown in FIGS. 6,  7 A, and  7 B. Further the tubular insert  43  has an arched lower section  44  which frames the upper part  42  of the aperture  21  of the tubular sleeve member  15 , as shown in FIGS. 6,  7 A &amp;  7 B. Also connected to the tubular insert  43  is a circular packer seal  45  with a fixed compression ring  46  positioned above the circular packer seal  45  for compressing the circular packer seal  45  into sealing engagement with the main well bore casing  11  for forming a seal there between when the tubular insert  43  is moved downward and the circular packer seal  45  is compressed against the up hole end  68  of the lower part  69  of the tubular sleeve member  15 . In this embodiment once the orientation key  40  is stopped in the mule shoe key way  23  in the proper orientation, continued down hole pressure is applied to the tubular member  24  and the orientation key  40  drives the upper part  41  of the tubular sleeve  15  or in this embodiment tubular insert  43  downward, which also moves the arched lower section  44 , which is formed in the tubular insert  43 , downward with the resulting change in the configuration of the aperture  21 , as best seen in FIGS. 6,  7 A &amp;  7 B. 
     In this embodiment the outside surface of the tubular insert  43  has sealing and gripping surfaces  47  for mating with sealing and gripping surfaces  48  located on the inside of the tubular sleeve member  15  when the two sealing and gripping surfaces  47  &amp;  48  are pushed together. Thus when the orientation key  40  drives downward on the mule shoe key way  23  it drives the tubular insert  43  with the sealing and gripping surfaces  47  into engagement with the sealing and gripping surfaces  48  to both seal the tubular insert  43  and the inside surface of the tubular sleeve member  15 . Once the sealing and gripping has occurred continued pressure on the tubular member  24  releases the tubular member  24  and stab in  54  from the orientation key  40  by shearing shear pins  56  for the final push to put the sealing member  25  into place against the seating surface  17  inside the tubular sleeve member  15  proximate the aperture  21  which has now had the configuration of the aperture  21  changed by the arched lower section  44  of the tubular insert  43  being moved down ward and the sealing gripping surfaces  47  ad  48  are mated. One of the functions for the adjustment of the configuration of the aperture  21  is to provide both a sealing engagement between the sealing member  25  positioned about the tubular member  24  and the seating surface  17  inside of the tubular sleeve member  15  proximate the aperture  21  and also between the tubular member  24  and the aperture  21  by the downward movement by the arched lower section  44  thus forming a seal at the junction of the lateral well bore  12  and the main well bore casing  11 , as shown in FIG.  8 . Even in some embodiments as shown in FIGS. 7A &amp; 7B, compressible material  61  is connected about the aperture  21  of the tubular sleeve member  15  for sealing the tubular member  24  when the aperture  21  is downwardly adjusted by the arched section  44 . 
     In yet other embodiments as shown in FIG. 8 the sealing member  25  has positioned thereon a compression seal gasket  49  for forming a compression seal when the sealing member  25  is brought into engagement with the seating surface  17  inside the tubular sleeve member  15  proximate the aperture  21  as the tubular member  24  is run into the main well bore casing  11 . 
     Another embodiment, as also show in FIGS. 8 and 9, shows a elastic tubular seal  50  about the sealing member  25  of the tubular member  24  which is in fluid communication by way of a one way check valve  51 , as best seen in FIG. 8, for receiving fluid  70  from the drill string  53  to expand the elastic tubular seal  50 . By expanding the elastic tubular seal  50  as the fluid  70  is received through the tubular member  24  and drill string  53 , the elastic tubular seal  50  expands against the tubular sleeve member  15  which forms the aperture  21  and against the tubular sleeve member  15  outside and proximate the aperture  21  for providing a seal which will prevent well fluid  63  movement either into or out of the aperture  21  and for holding the tubular member  24  and the tubular sleeve member  15  together against movement. Once the initial sealing as described above has been done then a pressure check of the seal formed between the lateral well bore  12  and the main well bore casing  11  can be conducted while all the equipment of the assembly  14  is in place in the well, as shown in FIG.  9 . This test is done by pressuring up the well fluids  63  or any other desired fluids in the well and checking for leaks. If the seal formed is not as desired, then additional fluid  70  may be pumped in to expand the elastic tubular seal  50  further until a desired seal is formed, as shown by FIGS. 8 &amp; 9. As those skilled in the art would appreciate the stab in  54  would have a cap  57  to allow the fluid  70  to have a pressure build up to perform this operation. Also those skilled in the art will appreciate the benefits of being able to test the seal before removing all the equipment of the assembly  14  used to form the seal and not have to reset up and run the sealing operation again, if it is not successful. Once the desired sealing is formed, as those skilled in the art will appreciate the fluid  70  which was pumped into the elastic tubular seal  50  will set up and become solid, like a cement, for forming a very rigid seal. Also as seen in FIG. 8, the stab in  54  is sealed in place by a well bore seal  58  located in the tubular member  24 , which holds until it is desired to pull the stab in  54  out of the tubular member  24 . Also as those skilled in the art will know the stab in  54  may be hydraulically disconnected form the tubular member  24  when it is desired to pull them from the main well bore casing  11 . 
     Once the seal between the lateral well bore  12  and the main well bore casing  11  is completed the deflection member  16  may be retrieved from the well as shown in FIG. 11 by running a drill string  53  with a male retrieving member  52  to engage with the female retrieving member  35  on the deflection member  16  and then pull the deflection member  16  from inside the tubular sleeve member  15  and clear of the window  13 . Once the deflection member  16  is removed from the main well bore casing  11  as shown in FIG. 13 the main well bore casing  11  is substantially clear and open for further well operations below the junction of the seal between the main well bore casing  11  and the lateral well bore  12 . In some cases it will be desired to seal the key cavity  59 , as shown in FIG. 11, which the key  18  would leave in the cement  65 , more securely than with just cement  65 , once the deflection member  16  and key  18  are removed. In such cases an impervious plug  60 , as shown in FIG. 12, would be set and sealed in the key cavity  59  using the mule shoe  22  and the mule shoe key way  23  with a running tool to locate and position the impervious plug  60  in the hole and seal it. The ability to set this impervious plug  60  in the key cavity  59  points out one of the benefits of the use of the assembly  14  of this invention not only for setting the impervious plug  60 , but also for reentry back into the lateral well bore at any later time. This is achieved by the mule shoe  22  and mule shoe key way  23  remaining in the main well bore casing  11  to give a point which can easily and specifically be located, for example, the key cavity  59 . By knowing the exact distance the key cavity  59  is from the mule shoe key way  23  on the tubular sleeve member  15  it can be easily found from the surface of the main well bore casing  11  and the impervious plug  60  put in place. Those skilled in the art will realize that this is a useful feature of this invention and will also realize that the overall inside diameter of the main well bore casing  11  with the tubular sleeve member  15  left behind in the main well bore casing  11  would not greatly reduce the inside diameter and thus allow other well operations to be conducted further down the main well bore casing  15 . 
     In certain applications the assembly  14  may be run in two separate runs, such that the deflection member  16  and tubular sleeve member  15  may be run into the main well bore casing  11  and used as a standard “Whip Stock” for setting lateral well bore liner  54 , or lateral well bore screens, etc. and then the tubular member  24  with the sealing member  25  positioned about the tubular member  24  may be run into the well on a later run to form the seal using a tubular member  24 , with a “Stab In”  54  to join the lateral well bore  12  and the main well bore casing  11  as shown in FIG. 10 without departing from the teachings of this invention. 
     It should be noted that the key  18  at least in some embodiments, as shown in FIG. 8, has a downwardly sloping front face  38  for grabbing on to the sill  20  of the window  13  and pulling the tubular sleeve member  15  in to very positive engagement against movement down hole. Further it should be noted that key  18  at least in this embodiment may also have downward sloping back face  39  for acting as a cam surface to drive the key  18  back into the spring receiving box  31  upon the deflector member  16  being removed from the tubular sleeve member  15  after completion of the seal operations. 
     It will be appreciated by those skilled in the art that the tubular sleeve member  15  is sized to fit into the main well bore casing  11  or other tubular member into which it may be used and is sized to receive the deflection member  16  and have the O-ring seal  27  of the deflection member  16  to seal the tubular sleeve members  15  from fluid flow through the inside diameter of the tubular sleeve member  15 . As those skilled in the art will appreciate the optimum would be for the inside diameter of the tubular sleeve  15  to be as large as possible and yet still receive the benefits of this invention because the larger the inside diameter of the tubular sleeve  15  the less the main well bore casing clearance would be reduced after the seal at the junction of the lateral well bore  12  and the main well bore casing  11  is completed and the deflection member  16  is removed. 
     The method of using the assembly  14  of this invention for forming a seal at the junction of a lateral well bore  12  drilled through a window  13  in at least a main well bore casing  12  comprising in one embodiment the steps of running a tubular member  24  with a sealing member  25  positioned about the tubular member  24  into the main well bore casing  11  which is functionally and releasablely connected to a deflector member  16  which is positioned in the tubular sleeve member  15  having an aperture  21  through at least one side of the tubular sleeve member  15 , and releasable sealed in the tubular sleeve member  15  and having an orientation key  18  positioned thereon. Then as the tubular sleeve member  15  is gently rotated while being lowered into the main well bore casing  11 , popping outwardly open the orientation key  18  for orientation of the deflection member  16  in the window  13  which is in the main well bore casing  11  when the orientation key  18  reaches the opening of the widow  13 . Next the step of the operator letting down on said tubular member  24  being run into the main well bore casing  11  to allow the popped open orientation key  18  to guide and orient the tubular sleeve member  15  and the deflection member  16  into position by following the sill  20  of the window  13 . Once the orientation key  18  reaches the down hole sill  52  or the key way  26  of the window, then fixingly and sealingly setting the tubular sleeve member  15  in the main well bore casing by continuing to let down on the drill sting  53  which is connected to the tubular member  24 . by stab in  54  or any other connecting means. Once the tubular sleeve member  15  is fixed and sealed, then the step of controllable releasing the controllable releasing member  37  functionally holding the tubular member  24  and the tubular sleeve member  15  together is accomplished by letting down on the tubular member  24 . Once released, continue letting down on the drill string  53  and tubular member  24  and/or any intermediate tubular goods until then the one orientation key  40  is in place and free for driving downward the tubular sleeve member  15  having an adjustable upper part  43  which is in mechanical communication with the aperture  21  for adjusting the aperture  21  until said controllably collapsible upper part  43  collapses which seals and sets the upper part of the tubular sleeve member  41  in the main well bore casing  11 . After the tubular sleeve member  15  is sealed and set then continued lowering of the tubular member  24  into the deflector member  16  in the tubular sleeve member  15  to deflect the tubular member  24  through the window  13  for seating the sealing member  25  positioned about the tubular member  24  into seating with the seating surface  17  inside the tubular sleeve member  15  proximate the aperture  21  in the tubular sleeve member  15 . Once the seating of the sealing member  25  with the seating surface  17  has occurred then pumping fluid  70  into the elastic tubular seal  50  through the tubular member  24  for sealing the window  13  and the lateral well bore  12 . After the sealing is completed then pulling the deflector member  16  out of the tubular sleeve member  15  and out to the main well bore casing to leave a substantially clear and clean main well bore  11  with the lateral well bore  12  and main well bore casing sealed. 
     Between the steps of pumping fluid  70  into the elastic tubular seal  50  and pulling the deflector member  16  out of the tubular sleeve  15 , may be the step of pressure testing the seal by pressuring up the well with well fluids  63 , or other fluid, to check the seal. If the seal is not as secure as desired then re-running the step of pumping fluid  70  into the elastic tubular seal  50  may be done again to higher pressures, possibly if desired, and a re-pressure testing of the seal again until the seal is as desired. All of this rechecking being done while all the equipment for forming the seal remains in place, which eliminates any need to reset up the equipment if the seal had failed. 
     While the preferred embodiments of the invention and the methods of their use have been described for the assembly for forming a seal at the junction of a lateral well bore drilled through a window in at least a main well bore casing it will be appreciated that other embodiments and methods may be used without departing from the spirit of the invention.