Patent Publication Number: US-10760355-B2

Title: Float shoe having concrete filled, eccentric nose with jets

Description:
BACKGROUND OF THE DISCLOSURE 
     During the construction of oil and gas wells, a borehole is drilled to depth, the drill string is removed, and casing is inserted. The annular space between the outside of the casing and the wall of the borehole is then conditioned for cementing by pumping conditioning fluid down the casing. The conditioning fluid flows radially outwardly from the bottom of the casing and passes upwardly through the annular space where it entrains debris and carries it to the surface. Finally, cement is pumped downwardly through the casing. The pumped cement squeezes radially outwardly from the bottom of the casing and passes upwardly into the annular space where the cement then sets. 
     Conventionally, a fill valve is disposed toward the downhole end of the casing. The fill valve prevents fluid from entering the casing from the borehole, but permits fluid (i.e., mud, conditioning fluid, cement, etc.) to flow from the casing into the borehole. The fill valve is normally incorporated in a float shoe or a float collar. The float shoe is fitted on the bottom of the casing, whereas the float collar is typically incorporated between two lengths of casing. 
       FIG. 1  illustrates a conventional float collar  10 A of the prior art. The collar  10 A includes a tubular housing  12  accommodating a fill valve  30  therein. The fill valve  30  has a valve member  36  that is generally mushroom shaped with a head biased upwardly against a valve seat  32  by a spring  38  circumjacent a stem of the valve member  36 . A base  34  in the seat  32  supports the valve member  36  and the spring  38 . 
     The interior  12  of the housing  12  has an annulus filled with high density cement  20  disposed therein. The cement  20  supports the fill valve  30  and has a passage  22  communicating with the fill valve  30 . During use, mud, conditioning fluid, and cement can flow through the passage  22  and the fill valve  30 , but fluid from the borehole is not permitted to pass uphole through the valve  30 . 
     The float collar  10 A is mounted with its box end  18  at the bottom of casing (not shown). The pin end  16  can attach to another extent of casing or tubular. Alternatively, a shoe  40  as in  FIG. 2A  with box thread  48  can thread to the pin end  16  of the collar  10 A to form a float shoe. The shoe  40  includes cement  44  inside its end that defines a passage  46  for communicating with the float shoe. 
     During use as a float collar, the casing having the float collar  10 A with the connected shoe  40  is run downhole in the wellbore. Once the casing is in position, mud is pumped down the casing. The mud flows through the fill valve  30  and then passes out the passage  46  in the shoe  40 . The mud flowing from the bottom of the casing then travels upwardly through an annulus between the casing and the wellbore to carry debris to the surface. Typically, mud is passed through the fill valve  30  for several hours. Conditioning fluid (usually referred to as “spacer fluid”) is then pumped down the casing. The conditioning fluid helps remove the mud and contains chemicals that will help the cement adhere to the casing. 
     After conditioning is complete, a charge of cement is pumped down the casing between a top plug and a bottom plug. After the bottom plug seats on (or near) the upper surface  24  of the float collar  10 A, increasing pressure is applied against the top plug until a burst disk in the bottom plug ruptures and permits the cement to flow downwardly into the float collar  10 A. The pressure applied to the cement by the top plug is transmitted to the head of the valve member  36 , which moves downwardly away from valve seat  32 , thereby permitting the cement to pass through the fill valve  30  and out the float shoe  40 . 
     When the top plug contacts the bottom plug, no further cement passes through the fill valve  30 . Pressure is then released on the top plug, and the fill valve  30  inhibits cement from flowing upwardly back inside the casing. After the cement has set, the top plug, bottom plug, fill valve  30 , annular cement  20  in the float collar  10 A, annular cement  44  in the shoe  40 , and any other cement below the shoe  40  is drilled out. 
     As noted above, a shoe  40  as in  FIG. 2A  can be mounted to a float collar  10 A to run in the casing in the borehole. The shoe  40  in  FIG. 2A  has a conventional nose  44  of cement defining a central passage  46  for communicating fluid (e.g., mud, conditioning fluid, and cement) out of the nose  40 . The cement  44  is used because it can be readily drilled out after cementing operations. 
     In some wellbores, various features of ledges, carvings, and irregularities in the borehole can hinder the running of the casing to the planned depth. To overcome these obstacles, a float shoe nose with a conical or eccentric shape is commonly used. The shape and the material of the nose are preferably of sufficient strength to overcome high loads, yet are easily drilled using a drill bit. Composite and aluminum materials have been used in the past for these types of noses on the end of the casing. 
     For example,  FIG. 2B  illustrates a composite nose  50  of the prior art for use on a float shoe  10 B. As before, the float shoe  10 B includes a tubular housing  12  accommodating a fill valve  30  therein. The interior  12  of the housing  12  has an annulus filled with high density cement  20  disposed therein to support the fill valve  30 . The cement  20  has a passage  22  in which the fill valve  30  is mounted. 
     The nose  50  is constructed of a composite material having wear resistant and drillable characteristics. Typically, fiberglass or some other composite material is used for the nose  50 . Because the nose  50  is composed of composite material, it can be given a conical, eccentric shape. In this way, the nose  50  not only serves to direct fluid, but the eccentric conical shape of the nose  50  can aid in run-in of the assembly by facilitating the passage of the assembly through the borehole. 
     At an upper end, the nose  50  fits into the housing  12  of the float shoe  10 B and is attached with a threaded connection  16 ,  56 . A central bore  52  of the nose  50  is aligned with the longitudinal bore  22  of the annular cement  20  in the interior  14  of the housing  12 . The nose  50  can also include a side port or jet  54  for the passage of fluid from the longitudinal bore  52  to the borehole (not shown). 
     As another example,  FIG. 2C  illustrates an aluminum nose  60  of the prior art for use on a float shoe  10 C. As before, the float shoe  10 C includes a tubular housing  12  accommodating a fill valve  30  therein (here, two fill valves are shown). The interior  12  of the housing  12  has an annulus filled high density cement  20  disposed therein to support the fill valves  30 . The cement  20  has a passage  22  in which the fill valves  30  are mounted. 
     Because the nose  60  is composed of aluminum, it can be given a conical or eccentric shape and may have external features, such as wear resistant nodules, ribs, or the like. In this way, the aluminum nose  60  not only serves to direct fluid, but the shape of the nose  60  and any external features can aid in the run-in of the assembly by facilitating the passage of the assembly through the borehole. 
     At an upper end, the nose  60  fits into the housing  12  of the float shoe  10 C and is attached thereto with a threaded connection  16 ,  66 . A central bore  62  of the nose  50  is aligned with the longitudinal bore  22  of the annular cement  20  in the interior  14  of the housing  12 . The nose  60  can also include a side port or jet  64  for the passage of fluid from the longitudinal bore  62  to the borehole (not shown). 
     Although the composite and aluminum noses  50 ,  60  on float shoes can be effective, the cost of these materials can increase the overall equipment cost. Side ports or jets for the noses  50 ,  60  are fabricated by drilling ports at an angle, which adds additional machine work and increases product cost. In addition to higher costs, aluminum materials of an aluminum nose  60  may be more difficult to drill up than composite materials of a composite nose  50 . Yet, the composite materials often break up into larger pieces that can obstruct the drilling assembly. 
     The subject matter of the present disclosure is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above. 
     SUMMARY OF THE DISCLOSURE 
     According to the present disclosure, a float shoe for a downhole tubular, such as casing, comprises a housing, a nose, a support, and a valve. The housing comprises a first material and defines a bore therethrough from a first end of the housing to a second end of the housing. The first end is attached to the tubular. The nose comprises a second material, extends from the second end of the housing, and defines an internal cavity. The nose has a first passage communicating a distal outlet of the nose toward the bore of the housing. The support comprises cement, is disposed in the bore of the housing, and is disposed in the cavity of the nose. The valve is supported by the support in the bore of the housing. The valve is disposed in communication between the first end of the housing and the first passage of the nose. 
     The nose can define a port or jet communicating the first passage outside a side of the nose. The first material of the housing can comprise a metallic material, while the second material of the shell can comprise a composite material. The second material for the nose can be other millable or drillable materials, including aluminum. 
     In one arrangement, the nose can comprise a shell having a third end, a fourth end, an outer wall, and an inner wall. The third end attaches to the second end of the housing, and the inner and outer walls extend between the third and fourth ends. The outer wall is disposed circumferentially about the inner wall and defines the internal cavity therebetween, which is filled with the cement of the support. The inner wall forms the first passage communicating the valve at the third end of the shell with the distal outlet at the fourth end of the shell. 
     The outer wall of the shell can converge eccentrically from the third end to the fourth end of the shell. The inner wall of the shell can form the first passage cylindrically from the third end to the fourth end. 
     The outer wall of the shell at the third end can include an outer rim open to the internal cavity and attaching to the second end of the housing. This outer rim can comprise a snap-in feature attaching to the second end of the housing. 
     The outer wall at the fourth end of the shell can enclose around the distal outlet of the inner wall. 
     A cross member can be disposed in the internal cavity and can define a second passage communicating the first passage of the inner wall with a port defined in the outer wall of the shell. 
     According to the present disclosure, a nose for a float shoe on a downhole tubular, such as casing, comprises a shell having a first end, a second end, an outer wall, and an inner wall. The first end attaches to the float shoe, and the inner and outer walls extend between the first and second ends. The outer wall is disposed circumferentially about the inner wall and defines an internal cavity therebetween, which is filled with cement. The inner wall forms a first passage communicating the float shoe at the first end of the shell with a distal outlet at the second end of the shell. Features discussed previously can apply equally to the current arrangement of the nose and the shell. 
     According to the present disclosure, a method of manufacturing a float shoe for a downhole tubular comprises not necessarily in sequence: positioning a valve in a bore of a housing for the float shoe having first and second ends, the first end configured to attach to the downhole tubular; extending the second end of the housing with a nose by attaching a shell to the second end of the housing, the shell defining an internal cavity communicating with the bore; filling an annular space around the valve with cement to support the valve disposed in the bore of the housing; filling the internal cavity of the shell with cement; and communicating the valve with a distal outlet of the nose via a first passage in the nose. 
     Attaching the shell to the second end of the housing can comprise snapping a rim of the shell inside the second end of the housing and can further comprise supporting the snapped rim of the shell inside the second end of the housing using the cement. 
     Filling the internal cavity of the shell with the cement can be performed before attaching the shell to the second end. The annular space around the valve can be filled with the cement after attaching the shell to the second end. 
     Filling the internal cavity of the shell with the cement can be performed after attaching the shell to the second end. The annular space around the valve can be filled with the cement during the filling of the internal cavity. 
     Attaching the shell to the second end of the housing can further comprise connecting the first passage of the shell with a side port in the shell by placing a cross member in the internal cavity and having a second passage to communicate the first passage with the side port. 
     To communicate the valve with the distal outlet of the nose via the first passage in the nose, an inner wall of the shell can extend in the cavity from the distal outlet of the nose to the valve in the housing. 
     The foregoing summary is not intended to summarize each potential embodiment or every aspect of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a float collar known in the art for use on casing run in a borehole. 
         FIG. 2A  illustrates a conventional nose of the prior art for use on casing or a float collar. 
         FIG. 2B  illustrates a composite nose of the prior art for use on a float shoe. 
         FIG. 2C  illustrates an aluminum nose of the prior art for use on a float shoe. 
         FIG. 3  illustrates a cross-sectional view of a nose of the present disclosure for use on a float shoe. 
         FIG. 4A  illustrates a partial cross-sectional view of the nose and the float shoe of  FIG. 3  in separate assembly. 
         FIG. 4B  illustrates a partial cross-sectional view of the nose of  FIG. 4A  assembled to the float shoe. 
         FIG. 5A  illustrates a partial cross-sectional view of another nose and a float shoe in separate assembly. 
         FIG. 5B  illustrates a partial cross-sectional view of the nose of  FIG. 5A  assembled to the float shoe. 
         FIG. 6A  illustrates a partial cross-sectional view of yet another nose and a float shoe in separate assembly. 
         FIG. 6B  illustrates a partial cross-sectional view of the nose of  FIG. 6A  assembled to the float shoe. 
         FIGS. 7A-7D  illustrate steps for assembling a nose and a float shoe of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE DISCLOSURE 
       FIG. 3  illustrates a float shoe  100  according to the present disclosure. The float shoe  100  includes a housing  110 , a nose  102 , a support  120 , and a fill valve  130 . The housing  110  is a tubular and is typically composed of a metallic material similar to that used for casing. The housing  110  defines a bore  120  therethrough from a first end  114  to a second end  116 . The first end  114  has a box thread that is attached to a pin end  74  of a tubular or casing  70 . 
     The nose  102  extends from the second end  116  of the housing  110  and defines an internal cavity  104 . The nose  102  has a flow passage  106  communicating a distal outlet of the nose  102  toward the bore  112  of the housing  110 . In addition to the fluid passage  106 , the nose  102  can also define at least one side port or jet  108  communicating the fluid passage  106  outside a side of the nose  102 . 
     The support  120  comprises cement, which is disposed in the bore  112  of the housing  110  and disposed in the cavity  104  of the nose  102 . The internal bore  112  of the housing  110  may have internal ribs, grooves, and the like to facilitate engagement with the cement support  120  filled inside. 
     The fill valve  130  is supported by the support cement  120  in the bore  112  of the housing  110  and is disposed in communication between the first end  114  of the housing  110  and the flow passage  106  of the nose  102 . During use, fluid including mud, conditioning fluid, and cement can flow through the fill valve  130 , but fluid from the borehole is not permitted to pass back uphole through the valve  130 . 
     For example, the fill valve  130  can have a valve member  136  that is generally mushroom shaped with a head biased upwardly against a valve seat  132  by a spring  138  circumjacent a stem of the valve member  136 . A base  134  in the seat  132  supports the valve member  136  and spring  138 . As noted above, the interior or bore  112  of the housing  110  has an annulus filled with the support  120  of high density cement disposed therein. The cement support  120  can define a central passage  122  that connects to the fill valve  130 , although the fill valve  130  may have an inlet feature. 
     As assembled, the float shoe  100  is mounted with its pin end  114  at the bottom of casing  70  or other tubular, and the nose  102  extends from the second end  116  of the housing  110 . During use, the casing  70  having the float shoe  100  and the nose  102  is run downhole in the borehole. Once the casing  70  is in position, mud is pumped down the casing  70 . The mud flows through the fill valve  130  and then passes out the fluid passage  106  in the nose  102 . The mud flowing from the bottom of the casing  70  then travels upwardly through an annulus between the casing  70  and the borehole (not shown) to carry debris to the surface. Typically, mud is passed through the fill valve  130  for several hours. Conditioning fluid (usually referred to as “spacer fluid”) is then pumped down the casing  70 . The conditioning fluid helps remove the mud and contains chemicals that will help the cement adhere to the casing  70 . 
     After conditioning is complete, a cement charge is pumped down the casing  70  between a top plug (not shown) and a bottom plug (not shown). (To avoid confusion with the cement support  120 , the pumped cement used to set the casing  70  in the borehole is referred to as a cement charge.) After the bottom plug seats on (or near) the upper surface  124  of the float shoe  100 , increasing pressure is applied to the top plug until a burst disk in the bottom plug ruptures and permits the cement charge to flow downwardly into the float shoe  100 . The pressure applied to the cement charge by the top plug is transmitted to the head of the valve member  136 , which moves downwardly away from valve seat  132 , thereby permitting the cement charge to pass through the fill valve  130 . 
     When the top plug contacts the bottom plug, no further cement charge passes through the fill valve  130 . Pressure is then released on the top plug, and the fill valve  130  inhibits the cement charge from flowing upwardly back inside the casing  70 . After the cement charge has set, the top plug, the bottom plug, the fill valve  130 , the annular cement support  120 , the nose  102 , and any other cement below the shoe  100  is drilled out. 
     As noted previously, some boreholes have various features of ledges, carvings, and irregularities that can hinder the running of the casing  70  to the planned depth. To overcome these obstacles, the nose  102  of the float shoe  100  has a conical and/or eccentric shape. 
     Turning to further details of the nose  102  as shown in  FIG. 3  and as shown in more detail in  FIGS. 4A-4B , the nose  102  includes a shell  140  composed of a plastic or a composite material. The shell  140  can also be formed of a thinner aluminum or other drillable metal. The shell  140  has a first end  141   a , a second end  141   b , an outer wall  150 , and an inner wall  154 . The first end  141   a  attaches to the housing  110  of the float shoe  100 , and the inner and outer walls  150 ,  154  extend between the first and second ends  141   a - b  of the shell  140 . The outer wall  150  is disposed circumferentially about the inner wall  154  and defines an internal cavity  142  therebetween. When assembled as shown in  FIG. 4B , this internal cavity  142  is filled with the support cement  120 . The inner wall  154  forms the fluid passage  106  communicating the housing  110  (more particularly the valve  130 ) at the first end  141   a  of the shell  140  with a distal outlet  144  at the second end  141   b  of the shell  140 . 
     As shown, the outer wall  150  of the shell  140  converges conically from the first end  141   a  to the second end  141   b  of the shell  140  and can come to an eccentrically closed end  152  enclosed around the distal outlet  144  of the inner wall  154 . For its part, the inner wall  154  of the shell  140  can form cylindrically from the first end  141   a  to the second end  141   b  to complete the fluid passage  106 . 
     As shown in  FIGS. 4A-4B , the outer wall  150  of the shell  140  at the first end  141   a  comprises an outer rim  151  open to the internal cavity  142  and attaching to the tubular housing  110  of the float shoe  100 . For example, the outer rim  151  can have a snap-in feature  148  attaching to the tubular housing  110 . In general, the snap-in feature  148  can include a lip, circumferential slot, indentation, teeth, ratcheting, or the like on the rim  151  that fits against a complementary lip, detent, shoulder, catch, or the like on the inside of the housing  110 . Other forms of attaching, such as threading, compression fitting, pinning, gluing, etc., can be used between the housing  110  and the shell  140 . The inner wall  154  of the shell  140  at the first end  141   a  has an inner rim  155  that communicates with the valve member  130  of the float shoe  100 . As shown in  FIG. 4B , the inner rim  155  can abut against the valve member  130  to communicate therewith. 
     For the side port or jet  108  of the nose  102 , at least one cross member  146  can be disposed in the internal cavity  142  of the shell  140  and can communicate the fluid passage  106  of the inner wall  154  with a port defined in the outer wall  150  of the shell  140 . This cross member  146  can be a tube formed or inserted in the cavity  142  and extending from one open end at the fluid passage  106  at the inner wall  154  to another open end at a hole in the outer wall  150  for the side port or jet  108 . 
     The annular space of the float shoe  100  connects with the inner cavity  142  of the shell  140  so that a continuous extent of the cement  120  as shown in  FIG. 4B  can fill the annular space and the cavity  142 . The continuous extent of the cement  120  is not completely necessary. At least a first extent of the cement  120  is needed to support the valve  130 , and at least a second extent of the cement  120  is needed to fill cavity  142  of the shoe  102 . These two extents can be separately formed and may have a gap (not shown) between them as long as the valve  130  can communicate with the fluid passage  106  and distal outlet  108  of the shoe  102 . As can be seen, once casing has been set with a cement charge, the valve member  130 , the cement support  120 , and the shell  140  can all be readily milled out. 
       FIG. 5A-5B  show an alternative shell  140  for the nose  102  of the float shoe  100 . Because the inner and outer walls  150 ,  154  of the shell  140  help contain and form the support cement  120  in the internal cavity  142 , it may not be necessary that the inner wall  154  of the shell  140  remain in place after assembly. Therefore, the inner wall  154  can be removed so that the support cement  120  defines the fluid passage  106  of the shell from the valve  130  to the distal outlet  144 . Rather than having the inner wall  154  be removable or be considered part of the shell  140 , the inner wall  154  may instead be a component of the fill valve  130  extending the outlet of the valve  130  to the distal outlet  144  of the shell  140 . 
       FIGS. 6A-6B  show another alternative shell  140  for the nose  102  of the float shoe  100 . Because the inner and outer walls  150 ,  154  of the shell  140  help contain and form the support cement  120  in the internal cavity  142 , it may not be necessary that the outer wall  150  of the shell  140  comes to a closed end enclosed around the distal outlet  144  of the inner wall  154 . Instead, the second end  141   b  can be open  153 , with the support cement  120  shaped as needed for the tip of the shoe  102 . The exposed cement  120  can be shaped by a temporary mold or by separate forming and/or shaving of excess cement  120 . 
     As can be seen by the examples of  FIGS. 4A through 6B , the shell  140  having the internal cavity  142  of the nose  102  and filled with support cement  120  can have a number of configurations. Overall, the outer wall  150  of shell  140  can contain the support cement  120  in the cavity  142  and can give the nose  102  a conical or eccentric shape. The outer wall  150  can be enclosed around a distal outlet  144  or may be at least partially open in which case the support cement  120  completes the shape of the nose. The inner wall  152  can be a cylindrical tube that communicates the fill valve  130  with the distal outlet  144  and can be either part of the shell  140  or part of the valve  130 , as described above. Also, the cylindrical tube that forms the inner wall  152  may removable so that the support cement  120  provides the fluid passage  106  between the valve  130  and the distal end of the nose  102 . 
       FIGS. 7A-7D  show one method of manufacturing a float shoe  100  for a downhole tubular according to the present disclosure. As shown in  FIGS. 7A-7B , a valve member  130  is disposed in the interior bore  112  of the housing  110 . One or more temporary fixtures (not shown) can be used to suspend the valve member  130  centrally in the empty interior  112  for the purposes of manufacture. 
     The shell  140  of the nose  102  is arranged with the inner cavity  142  open to the lower end of the housing  110 . The shell  140  can be composed of a unitary piece of material formed by molding, machining, and the like. Alternatively, the shell  140  can be constructed from two or more pieces separately manufactured by molding or the like, machined as necessary, and assembled together. 
     In a brief example, the outer wall ( 150 ) of the shell  140  can be formed as a first cupped shaped piece, the inner wall ( 154 ) can be formed as a second tubular piece, and a port ( 108 ) can be formed as a third tubular piece. A cross port  108  can be machined in the inner wall ( 154 ) and the outer wall ( 150 ) for the cross member ( 146 ), and an outlet can be machined in the outer wall ( 150 ) for connection to the inner wall ( 154 ) to form the distal outlet  144 . The pieces can then be assembled and affixed appropriately to complete the assembly of the shell  140 . 
     As shown in  FIG. 7C , the shell  140  is attached to the second end of the housing  110  using snap-in features, threading, or the like, as already noted. The internal cavity  142  of the shell  140  communicates with the hollow interior  112  of the housing  110 . The inner rim  155  of the inner wall  154  can communicate the valve member  130  with a distal outlet  144  of the nose  102 . 
     As shown in  FIG. 7D , the annular space around the valve member  130  is filled with cement  120  to support the valve member  130  in the housing  110 . A removable fixture (not shown) can be used to create the inlet of the inner passage  122  through the cement  120  if the valve member  130  does not include such an inlet already. 
     As also shown in  FIG. 7D , the internal cavity  142  of the shell  140  is filled with the cement  120 . In general, the internal cavity  142  of the shell  140  along with the annular space of the housing  110  can be filled together with the cement  120  after the shell  140  has been attached to the housing  110 . However, alternative steps can be performed to fill the assembly with the support cement  120 . 
     In one alternative, the internal cavity  142  of the shell  140  can initially be filled at least partially with the cement  120  before attaching the shell  140  to the housing  110 . In fact, the shell  140  can be filled at least partially with the cement  120  and allowed to cure before being attached. Either way, the shell  140  with the cured cement  120  can be attached to the housing  110 , which can then be separately filled with cement  120  to complete the assembly. 
     In another alternative, the interior of the housing  110  can be initially filled with the cement  120  and cured. The shell  140  can be filled with cement  120  and then attached to the housing  110 . 
     In arrangements in which snap-in features are used to attach the shell  140  to the housing  110 , the cement  120  is preferably used to support the attachment by keeping the shell  140  engaged in the end of the housing  110 . Therefore, during manufacture, at least the area around the attachment between the shell  140  and the housing  110  is preferably filled with cement  120  after the attachment so the cement  120  can cure in place to support the attachment. 
     The nose  102  disclosed herein overcomes issues of drillability and cost found with conventional noses. As disclosed above, the nose  102  includes a composite preformed/molded skin or shell  140  that attaches to the bottom of the housing  110  of the float shoe  100  and that can provide a desired eccentric shape. The molded shell  140  preferably has sufficient resilience to support the placement of the valve  130  and to provide for side ports or jets. 
     During run-in, the shell  140  remains attached to the float shoe  100  and forms the required eccentric geometry to facilitate passage through a borehole. Being filled with cement  120 , the shell  140  provides sufficient strength and drillability at a much-reduced cost. The thickness of the shell  140  can be configured as needed for the application at hand and the material used. The shell  140  can have any accepted shape typically used for fully composite or aluminum noses. Likewise, the shell  140  can have any external features, such as nodules, ribs, and the like typically used on a nose of a float shoe. 
     Cement is widely accepted as a having sufficient strength and drillability to create an acceptable float shoe nose. By using the shell  140  filled with the support concrete  120 , the nose  102  has an eccentric shape that can be consistently manufactured. Moreover, the high compressive strength material of the cement is readily drillable and provides sufficient resistance to set down weight. 
     The foregoing description of preferred and other embodiments is not intended to limit or restrict the scope or applicability of the inventive concepts conceived of by the Applicants. It will be appreciated with the benefit of the present disclosure that features described above in accordance with any embodiment or aspect of the disclosed subject matter can be utilized, either alone or in combination, with any other described feature, in any other embodiment or aspect of the disclosed subject matter. 
     In exchange for disclosing the inventive concepts contained herein, the Applicants desire all patent rights afforded by the appended claims. Therefore, it is intended that the appended claims include all modifications and alterations to the full extent that they come within the scope of the following claims or the equivalents thereof.