Abstract:
A bridge style fractionation plug for use in a wellbore to separate a lower fractionation zone from an upper fractionation zone with no communication between the zones.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The current application claims priority to and the benefit of U.S. Provisional Patent Application Ser. No. 61/602,019 filed Feb. 22, 2012, entitled “BRIDGE STYLE FRACTIONATION PLUG”. This reference is incorporated in its entirety. 
    
    
     FIELD 
     The present embodiments generally relate to a bridge plug for use in isolating fractionation zones in a wellbore. 
     BACKGROUND 
     A need exists for a fractionation plug which can avoid being preset in the wellbore while simultaneously separating the wellbore into separate zones. 
     A further need exists for a fractionation plug that can quickly and securely engage with the crown of another fractionation plug, which can prevent fractionation plugs from spinning during drill-out. 
     The present embodiments meet these needs. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The detailed description can be better understood in conjunction with the accompanying drawings as follows: 
         FIG. 1A  depicts a mandrel according to one or more embodiments. 
         FIG. 1B  depicts another mandrel according to one or more embodiments. 
         FIG. 1C  depicts an additional mandrel according to one or more embodiments. 
         FIG. 2  is a perspective view of a fractionation plug according to one or more embodiments. 
         FIG. 3  is a cut view of the fractionation plug of  FIG. 2  along line X-X. 
         FIG. 4A  depicts a schematic of a first setting mechanism according to one or more embodiments. 
         FIG. 4B  depicts a schematic of a second setting mechanism. 
         FIG. 4C  depicts a schematic of a third setting mechanism. 
         FIG. 5  depicts a schematic of two fractionation plugs disposed within a wellbore. 
         FIG. 6  depicts a cross sectional view of a load ring disposed about a mandrel wherein one or more set screws are disposed through the load ring. 
         FIG. 7  depicts a tapered nose cone having a beveled distal end. 
     
    
    
     The present embodiments are detailed below with reference to the listed figures. 
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Before explaining the present apparatus in detail, it is to be understood that the apparatus is not limited to the particular embodiments and that it can be practiced or carried out in various ways. 
     The present embodiments generally relate to a bridge style fractionation plug. 
     The bridge style fractionation plug can be used in a wellbore and can include a mandrel. 
     An embodiment of the bridge type fractionation plug allows a work over team to pressure up on wellbore casing before perforating a fractionation zone to ensure that the plug is holding; enabling successful separation of two fractionation zones. 
     The bridge type fractionation plug does not allow fractionation fluids, sand, or chemicals to penetrate a zone below the bridge plug; preventing loss of fractionation fluids, thereby insuring maximum fractionation in the correct fractionation zone. 
     These plugs can be used for cement jobs in the wellbore due to the solid construction of the bridge plug. 
     The mandrel can include a crown engagement and a setting mechanism receiving end. 
     The crown engagement can have a diameter larger than the setting mechanism receiving end. 
     A mandrel shoulder can be formed between the crown engagement and the setting mechanism receiving end. A load ring can rest on the mandrel shoulder. 
     A first slip can be adjacent to the load ring. A first slip backup can be adjacent to the first slip. A first lubricating spacer can be adjacent to the first slip backup and a first secondary seal. 
     A primary seal can be adjacent to the first secondary seal. A second secondary seal can be adjacent to the primary seal. 
     A second lubricating spacer can be adjacent to the second secondary seal, which can include a second slip backup adjacent to the second lubricating spacer. The second slip can be adjacent to the second slip backup. 
     A removable nose cone can be disposed over the mandrel and can be adjacent to the second slip backup. 
     The removable nose cone can include a double bevel or tapered engagement. The tapered engagement can be composed of a first sloped face, a second sloped face, and a tapered face. 
     A central annulus can be formed in the center of the sloped faces of the tapered engagement. The tapered engagement can be integrated with a nose cone body which can form a pump down ring groove. 
     An embodiment can include a plurality of pressure relief grooves which can extend longitudinally. The pressure relief grooves can be disposed on an outer surface of the tapered engagement. 
     A facial seal can be formed in the setting mechanism receiving end of the mandrel where a bridge plug setting mechanism can be threaded into the setting mechanism receiving end between the facial seal and the removable nose cone. 
     The bridge plug setting mechanism can include a setting mechanism body which can engage the facial seal. The bridge plug setting mechanism can also include a setting mechanism load shoulder. 
     An extension can extend from the setting mechanism load shoulder into the removable nose cone. For example, in one or more embodiments the extension can be about 0.47 inches long from the setting mechanism load shoulder to the face of the extension. 
     Engaging threads can extend over an outer surface of the setting mechanism body. The engaging threads can extend at least a portion of the setting mechanism body. 
     The engaging threads can screw into the internal threads of the bridge plug setting mechanism receiving end. 
     The setting mechanism body can include a first bridge plug setting mechanism chamber with a first diameter and a second bridge plug chamber with a second diameter. The engaging threads can extend into a portion or the entire first bridge plug setting mechanism chamber. 
     The second diameter can be larger than the first diameter, which can create a bridge plug shoulder. For example, in one or more embodiments the first diameter can be 0.95 inches and the second diameter can be 1.145 inches. 
     Shear threads can be formed inside the second bridge plug chamber. Shear threads can allow for threadable connection between the setting mechanism and a setting tool, such as a wireline setting tool. 
     The bridge style fractionation plug can include a crown engagement that can be detachable from the mandrel. The crown engagement can have a plurality of grooves in the top portion, such as from about four grooves to about six grooves. The grooves can provide a secure engagement with the nose cone of an adjacent plug. 
     The bridge style fractionation plug can include a setting mechanism with left handed threads. The left handed threading can be used to prevent loosening of the bridge plug, such as when the setting tool is inserted and tightened into the second bridge plug setting mechanism chamber. 
     The bridge style fractionation plug can include a mandrel. A mandrel can be composed of a metal, a non-metallic composite, or combinations thereof, such as a mandrel made from a glass and resin composite. 
     The bridge style fractionation plug can include slips made from a metal, non-metallic, composite, or combinations thereof. 
     Turning now to the Figures,  FIG. 1A  depicts a mandrel according to one or more embodiments. 
     The mandrel  12   a  can be used to form a portion of the bridge fractionation plug. 
     The mandrel  12   a  can have a first end  102  and a second end  150 . The mandrel  12   a  can have an overall length from 1 foot to 4 feet. The outer diameter of the mandrel  12   a  can be from 2 inches to 10 inches. 
     The mandrel  12   a  can have a crown engagement  20  formed in the first end  102 . 
     The first end  120  can have a first diameter that is larger than a second diameter of the second end  150 . For example, in one or more embodiments, the first diameter can be 0.75 inches and the second diameter can be 2.25 inches. 
     A mandrel shoulder  142  can be formed between the first end  102  and the second end  150 . The mandrel shoulder  142  can be of varying angles, such as from about 10 degrees to about 25 degrees. 
     The second end  150  can have a first setting mechanism receiving portion  152   a , which can have a facial seal  156   a  and first internal threads  154   a . The facial seal can be made from an elastomer, urethane, TEFLON™ brand polytetrafluoroethylene, or similar durable materials. The facial seal  156   a  can be one or more O-rings, E-rings, C-rings, gaskets, end face mechanical seal, or combinations thereof. The first setting mechanism receiving portion  156   a  can be used when the operating pressure is less than 8,000 psi. 
     An anti-rotation ring groove  140  can be formed into the first end  102 . The anti-rotation ring groove  140  can secure an anti-rotation ring, not shown in this Figure, about the mandrel  12   a . The anti-rotation groove prevents the fractionation plug from becoming loose and falling off of a plug setting tool. The anti-rotation groove creates a tight fit between the anti-rotation seal and the fractionation plug setting sleeve. The anti-rotation ring can be made from elastomeric, TEFLON™ brand polytetrafluoroethylene, urethane, or a similar sealing material that is durable and able to handle high temperatures. 
       FIG. 1B  depicts another embodiment of a mandrel  12   b . The mandrel  12   b  can be substantially similar to the mandrel  12   a . The mandrel  12   b , however, can have a second setting mechanism receiving portion  152   b  formed adjacent to the first end  102 . The second setting mechanism receiving portion  152   b  can have one or more seals  159 . The second setting mechanism receiving portion  152   b  can have one or more second internal threads  154   b . The second setting mechanism receiving portion  152   b  can be used at any pressure. 
       FIG. 1C  depicts another embodiment of a mandrel  12   c . The mandrel  12   c  can be substantially similar to the mandrel  12   a , but can include the first setting mechanism receiving portion  152   a  and the second setting mechanism receiving portion  152   b . The first setting mechanism receiving portion  152   a  can have first internal threads  154   a . The second setting mechanism receiving portion can have second internal threads  154   b.    
       FIG. 2  is an isometric view of an illustrative fractionation plug according to one or more embodiments. 
     The fractionation plug can include a mandrel  12 , which can be any mandrel described herein. One or more slips, such as a first slip  310  and a second slip  312  can be disposed on the mandrel  12 . 
     The slips  310  and  312  can be made from metallic or non-metallic material. The slips  310  and  312  can have segments that bite into the inner diameter of a casing of a wellbore. The first slip  310  can be adjacent a load ring  380 , and the second slip  312  can be adjacent a removable nose cone  348 . The first slip  310  and the second slip  312  can be bidirectional slips, unidirectional slips, or any other slip configured that are used in downhole operations. 
     The mandrel  12  can also have one or more slip backups disposed thereon. A first slip backup  320  can be adjacent to the first slip  310 . At least a portion of the first slip backup  320  can be tapered to at least partially nest within a portion of the inner diameter of the first slip  310 . A second slip backup  322  can be adjacent the second slip  312 . At least a portion of the second slip backup  322  can be tapered to at least partially nest within a portion of the inner diameter of the second slip  312 . The slip backups can force the adjacent slip to expand into the inner diameter of the casing of the wellbore. 
     The slip backups can expand the first secondary seal  339 , the second secondary seal  341 , and the large primary seal  340 . These seals can be made of any sealing material. Illustrative sealing material can include rubber, elastomeric material, composite material, or the like. These seals can be configured to withstand high temperatures, such as from 180 degrees Fahrenheit to 450 degrees Fahrenheit. 
     A first lubrication spacer  342  and a second lubrication spacer  344  can be disposed on the mandrel  12 . The lubrication spacers can be made of a material that can allow free movement of the adjacent components such as TEFLON™ brand polytetrafluoroethylene, plastic, polyurethane. The first and second lubrication spacers are each tapered on one side and fit into the slip backups. The first and second lubrication spacers can range in length from 1 inch to 3 inches. 
     The first lubrication spacer  342  can be disposed adjacent the first slip back up  320 . The first lubrication spacer  342  can be disposed between the first slip back up  320  and the first secondary seal  339 . 
     The second lubrication spacer  344  can be disposed about the mandrel  12  adjacent the second slip backup  322 . The second lubrication spacer  344  can be disposed between the second secondary seal  341  and the second slip backup  322 . 
     The mandrel  12  can also have a removable nose cone  348  disposed thereon. The removable nose cone  348  can have one or more pressure relief grooves  359  formed therein. The removable nose cone  348  can be of various lengths and have faces of various angles. The removable nose cone can be 6 inches long and can have a first sloped face of 45 degrees and a second sloped face of 45 degrees tapering to a point together. The removable nose cone  348  can have a central annulus  352 . The diameter of the central annulus can range from ⅝ of an inch to 3 inches. The removable nose cone  348  can be disposed about or connected with the mandrel  12  opposite the crown engagement  20 . A pump down ring  360  can be disposed about the removable nose cone  348 . 
     The load ring  380  can be disposed about the mandrel  12  adjacent or proximate to the crown engagement  20 . The load ring  380  can reinforce a portion of the mandrel  12  to enable the mandrel  12  to withstand high pressures. The load ring  380  can be made from a composite material containing glass and epoxy resin or polyamide cured material that is able to be machined, milled, cut, or combinations thereof. The load ring can be from 1 inch to 3 inches in length and 2 inches to 8 inches in diameter. 
       FIG. 3  is a cut view of the fractionation plug of  FIG. 2  along line X-X. 
     The fractionation plug  300  can have the mandrel  12 . The mandrel  12  can have a first setting mechanism receiving portion  152   a.    
     A setting mechanism  390  can be inserted in the first setting mechanism receiving portion  152   a . The setting mechanism can have a solid portion. The setting mechanism can threadably connect to the first setting mechanism receiving portion  152   a . The setting mechanism  390  can be any setting mechanism, such as those described herein. 
     The removable nose cone  348  can be supported by the mandrel, the setting mechanism  390 , or any combination thereof. 
     An anti-rotation ring  370  can be secured in the anti-rotation ring groove  140 . 
     The load ring  380  can rest on a mandrel a load ring seat  382  adjacent the load shoulder. 
     Also shown are pump down ring  360 , the pump down ring groove  359 , the first slip  310 , the second slip  312 , the first slip backup  320 , the second slip backup  322 , a large primary seal  340 , the first lubrication spacer  342 , the second lubrication spacer  344 , and the central annulus  352 . 
     The crown engagement  20  is also viewable in this Figure. The crown can be integral with the mandrel  12  as a one piece structure. In an embodiment, such as the 4½ inch in diameter mandrel, the crown can have 6 grooves formed by 6 points that extend away from the mandrel  12 , creating an engagement that securely holds another nose cone to the plug for a linear connection of two plugs in series. 
       FIG. 4A  depicts a schematic of a first setting mechanism  400  according to one or more embodiments. 
     The first setting mechanism can have an extension  302 . The first setting mechanism can have a solid end  305 . The solid end  305  can be used to isolate zones in a wellbore. 
     The first setting mechanism  400  can have a load shoulder  301 . The load shoulder  301  and the extension  302  can support the removable nose cone. 
     The first setting mechanism  400  can have a one or more engaging threads  393  formed on an outer diameter thereof. 
     A first bridge plug setting mechanism chamber  309  can be formed in the bridge plug  400 . The first bridge plug setting mechanism chamber  309  can have a first diameter. A second bridge plug setting mechanism chamber  311  can also be formed in the bridge plug. The second bridge plug setting mechanism chamber can have a second diameter. 
     The first diameter can be less than the second diameter creating a stop shoulder  307  to allow the seating of a setting tool. The second bridge plug setting mechanism chamber can have shear threads  313  to engage with the setting tool. 
       FIG. 4B  depicts a schematic of a second setting mechanism  600 . 
     The second setting mechanism  600  can include the extension  302 . The extension  302  can have one or more seal grooves  605 . The seal grooves  605  can support one or more seals  610 . 
     The second setting mechanism  600  can have the first bridge plug setting mechanism chamber  309  and the second bridge plug setting mechanism chamber  311  formed therein. The second setting mechanism  600  can have one or more shear threads  313  formed on an inner diameter of the second chamber  311 . 
     The second setting mechanism  600  can include a load shoulder  301 . The second setting mechanism  600  can also have one or more engaging threads  393  formed on an outer diameter thereof. 
     The second setting mechanism  600  can also include a tightening groove  324 . The second setting mechanism  600  can be engaged with the second setting mechanism receiving portion. 
     The second setting mechanism  600  can include the shoulder  307  that acts like a setting tool stop on the bridge. 
       FIG. 4C  depicts a schematic of a third setting mechanism  700 . 
     The third setting mechanism  700  can have the extension  302 . The extension  302  can have one or more seal grooves  605 . The seal grooves  605  can support one or more seals  610 . 
     The third setting mechanism  700  can include a load shoulder  301 . The third setting mechanism  700  can also have one or more engaging threads  393  formed on an outer diameter thereof. The third setting mechanism  700  can also include a tightening groove  324 . 
     The third setting mechanism  700  can include a threaded chamber  710  that can have one or more shear threads  313  formed on an inner diameter thereof. The third setting mechanism  700  can include an additional chamber  705 . 
       FIG. 5  is a schematic of two fractionation plugs disposed within a wellbore  501 . 
     As depicted, the wellbore  501  can have a perforated casing  500  and two hydrocarbon bearing zones  530  and  532 . 
     The embodiments of the fractionation plug described herein can be used within casing or within production tubing. For example, in one or more embodiments, the fractionation plug can be used within the wellbore casing. 
     In operation, coil tubing, wire lines, or other devices, which are not shown, can be used to place the fractionation plugs  510  and  520  into the wellbore  501 . The fractionation plugs  510  and  520  can isolate the hydrocarbon bearing zones  530  and  532  from one another. 
     Once the plug is at a designated location, the setting tool can pull the mandrel, holding the outer components on the mandrel, which can compress the outer components, the slips, and the slip backups for engagement with the casing of the wellbore. 
     Once the plug is set in place, completion or workover operations can be performed. 
       FIG. 6  depicts a cross sectional view of a load ring disposed about a mandrel wherein one or more set screws are disposed through the load ring. The load ring  380  can be disposed about the mandrel  12 . One or more shear pins  700   a  and  700   b  can be disposed through the load ring  380  and engage the mandrel  12 . For example, the shear screws can extend ⅛ th  of an inch into the mandrel  12 . The shear pins  700   a  and  700   b  can prevent premature movement of the load ring  380 . 
       FIG. 7  depicts a tapered nose cone having a beveled distal end. The removable nose cone  348  can have two slanted faces, one slanted face  709  is shown, and a pair of bevels  710  and  712  on a distal end thereof. The bevels  710  and  712  can be twenty degree bevels. The bevels help to reduce the risk of the removable nose cone  348  catching on a portion of a wellbore, reducing the likelihood of a premature set. 
     While these embodiments have been described with emphasis on the embodiments, it should be understood that within the scope of the appended claims, the embodiments might be practiced other than as described herein.