Abstract:
In one embodiment a method and apparatus for an improved ball dropper is provided. In one embodiment the method and apparatus can be used to drop various objects into the well bore from the rig. In one embodiment, when the well is pressurized the tool can be loaded with one or more items to be dropped.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This is a continuation of U.S. patent application Ser. No. 11/460,520, filed 27 Jul. 2006, (now U.S. Pat. No. 7,281,589), which is incorporated herein by reference and priority to which is hereby claimed. 
   U.S. Provisional Patent Application Ser. No. 60/805,688, filed on 23 Jun. 2006 is incorporated herein by reference. 
   Priority of U.S. Provisional Patent Application Ser. No. 60/805,688, filed on 23 Jun. 2006, is hereby claimed. 
   U.S. Provisional Patent Application Ser. No. 60/703,590, filed on 29 Jul. 2005 is incorporated herein by reference. 
   Priority of U.S. Provisional Patent Application Ser. No. 60/703,590, filed on 29 Jul. 2005, is hereby claimed. 

   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable 
   Reference To A “Microfiche Appendix” 
   Not applicable 
   BACKGROUND 
   This invention relates to tools for dropping balls into a tubing or casing string of a well bore. 
   In the course of operating downhole tools in an oil or gas well, it is sometimes necessary to release one or more variously sized balls or plugs from the surface into the tubing or casing string. The devices used for dropping balls or plugs are sometimes referred to as ball droppers, ball dropping heads, or cementing heads, plug containers or ball dropping heads. 
   A common method of releasing balls in these types of devices involves the use of linear actuators which are operated by either being rotated by a screw mechanism from the outside of the container or by a remote controlled piston on the outside of the container. The nature of these linear actuators is such that they protrude from the side of the container far enough to be cumbersome to use and are sometimes a problem on the rig floor. Because of the extension of the linear actuators, the operator may not be able to rotate the container because the distance between the bails is not sufficient to clear the actuators and allow them to rotate freely. 
   Additionally, prior art ball dropping tools must be pre-loaded, i.e., they cannot be loaded with balls when the tools are installed in a pressurized string of tubing or tubulars. Accordingly, where additional balls are required to be dropped while the tools are in the drill string, then, before loading the dropping tool, pressure must be relieved from the string of tubing or tubulars. Furthermore, in many cases prior art ball droppers must be removed from the line when being loaded with balls. 
   Various embodiments solve one or more of these problems by providing a compact mechanism for releasing balls or other items into the tubing or casing string even while the string pressurized. A tool is provided permitting easy release of one or more balls. Additionally, at least a portion of the ball loading section of can be fluidly sealed from the remainder of the tool. 
   While certain novel features of this invention shown and described below are pointed out in the annexed claims, the invention is not intended to be limited to the details specified, since a person of ordinary skill in the relevant art will understand that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation may be made without departing in any way from the spirit of the present invention. No feature of the invention is critical or essential unless it is expressly stated as being “critical” or “essential.” 
   BRIEF SUMMARY 
   The apparatus of the present invention solves the problems confronted in the art in a simple and straightforward manner. In one embodiment a method and apparatus for an improved ball dropper is disclosed. In one embodiment the method and apparatus can be used to drop various objects into the well bore from the rig. 
   In one embodiment, when the well is pressurized the tool can be loaded with one or more items to be dropped. 
   In one embodiment, items to be dropped can be sequentially loaded into the tool. In one embodiment a smaller item is dropped first and then a larger item dropped thereafter. 
   In one embodiment, a side drop passage is contained in an enlarged area. 
   In one embodiment, items of different sizes and/or shapes are dropped. 
   In one embodiment, items of different sizes and/or shapes are sequentially dropped. 
   In one embodiment, a plurality of items are simultaneously dropped. 
   In one embodiment, a plurality of items of different sizes and/or shapes are simultaneously dropped. 
   In one embodiment, the tool is used to engage or disengage a downhole tool, such as a jet washing tool. 
   In one embodiment a method of dropping a ball into a well comprising the steps of positioning a ball drop apparatus above the well, the apparatus comprising a main body section having upper and lower portions; a main passage through the main body section from the upper portion to the lower portion; a side drop passage which intercepts the main passage; a seal operatively connected to the side drop passage, separating the side drop passage into upper and lower portions, and having open and closed states; and a cap operative sealing the upper portion of the side drop passage. The method further comprises the steps of opening the seal to allow an item to drop from the side passage to the main passage and down the well. 
   In one embodiment a pressure equalization control can be used to equalize the pressure above and below the seal operatively connected to the side drop passage. In one embodiment the equalizing control is controlled by a handle which rotates. 
   In one embodiment a vent control can be used to vent pressure either above and/or below the seal operatively connected to the side drop passage. 
   The step of positioning preferably comprises attaching the ball drop apparatus to a top drive unit and lowering the ball drop apparatus with the top drive unit toward the well. 
   In one embodiment the method includes the additional step of checking to determine whether the item dropped failed to activate a downhole tool and then dropping a second item to activate the downhole tool. 
   In one embodiment, a means of circulating fluids through the drill string prior to, and after release of, the balls, is provided. 
   In one embodiment multiple items can be dropped simultaneously from multiple locations in the method and apparatus. 
   In one embodiment a method and apparatus for use with top drive units is provided. 
   In one embodiment, the ball dropping tool can also improve conditions for the rig hands where it can be remotely controlled from the floor of the rig. 
   The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein: 
       FIG. 1  is a front view of a preferred embodiment of the tool. 
       FIG. 2  is a top view of the tool of  FIG. 1 . 
       FIG. 3  is a side view of the tool of  FIG. 1 . 
       FIGS. 4A and 4B  are sectional views taken along line  4 - 4  of  FIG. 3 . 
       FIG. 5  is an exploded perspective view of various components of the tool of  FIG. 1 . 
       FIG. 6  is a perspective view of the tool of  FIG. 1 . 
       FIG. 7  is a perspective view of the tool of  FIG. 1 , wherein various items are shown in phantom lines. 
       FIG. 8A  is an exploded perspective view of an alternative tool having two second passages, which can assist in the quick or simultaneous dropping of multiple objects. 
       FIG. 8B  is an exploded perspective view of another alternative tool having four second passages, which can assist in the quick or simultaneous dropping of multiple objects. 
       FIG. 9  is an exploded view of a valve which can be used in one embodiment. 
       FIGS. 10A and 10B  are perspective and side views of one embodiment for an equalizing control where the equalizing control is shown in a closed state. 
       FIGS. 11A and 11B  are respectively a sectional view of the equalizing control of  FIG. 10B  taken along the line  11 - 11  and an enlarged view of  FIG. 11A . 
       FIG. 12  is the equalizing control of  FIG. 10A  shown in an open state. 
       FIGS. 13A and 13B  are respectively a sectional view of the equalizing control of  FIG. 10A  taken along the line  13 - 13  and an enlarged view of  FIG. 13A . 
       FIG. 14  is a perspective view of a cap for second passageway. 
   

   DETAILED DESCRIPTION 
   Detailed descriptions of one or more preferred embodiments are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in any appropriate system, structure or manner. 
     FIG. 1  is a front view of a preferred embodiment of tool  10 .  FIG. 2  is a top view of tool  10 .  FIG. 3  is a side view of tool  10 .  FIG. 4  is a sectional view of tool  10  taken along line A-A of  FIG. 3 .  FIG. 5  is an exploded perspective view of various components of tool  10 .  FIG. 6  is a perspective view of tool  10 . 
   Tool  10  can comprise body  20  which includes enlarged portion  35 . Body  20  can include main passage  80  which fluidly connects top  60  to bottom  70 . Body  20  can also include second passage  100  which is fluidly connects enlarged portion  35  to main passage  80 . Body  20  can be formed from a single forging. 
   Second passage  100  is preferably angled in relation to main passage  80 . Second passage  100  can include upper portion  110  and lower portion  120 . Preferably, body  20  is manufactured from a single piece of stock metal (e.g., 4140 steel). Preferably, the range of angles between second passage  100  and main passage  80  is between about 0 and 90 degrees, about 5 and 85 degrees, about 10 and 80 degrees, about 15 and 75 degrees, about 20 and 70 degrees, about 25 and 65 degrees, about 30 and 60 degrees, about 35 and 55 degrees, about 40 and 50 degrees. Additional preferred angles include being about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, and 85 degrees. In one embodiment second passage can be curved or have varying along its length. 
   Preferably, second passage  100  is included in enlarged portion  35 , reducing the risk that a mechanical failure or leak will occur regarding the fluid connection between main passage  80  and second passage  100 . 
   Upper portion  110  can be sealable in relation to lower portion  120  through seal  198 . Seal  198  can be valve  200 ( preferably a ball valve) or other sealing means. Valve  200  can be opened and closed through valve operator  230 , which can be a valve handle or automatic valve operator. Valve handle can include a connecting portion  234  which can connect to an outside tool, such as a wrench (e.g., an allen wrench). Valve operator  230  can be separable from valve  200 . 
     FIG. 9  is an exploded view of one embodiment of valve  200 . Valve  200  can comprise cannister  242 , valve ball  220 , valve operator  230 , spring  244 , lower seat and teflon  248 , upper seat and teflon  256 , cage/seat fastener  257 , lower seat poly seal  258 , upper and lower seat teflon rings  259 , locking segment set  268 , support ring  272 , spiral retainer ring  276 , upper seat o-ring  280 , upper seat backup ring  282 , and cannister o-ring  284 . Valve operator  230  can comprise stem  260 , stem bearing assembly  264 , stem o-ring  288 , and stem back up ring  292 . Stem  260  can be operatively connected (via sliding) to valve ball  220  through stem link  252  and a slot on valve ball  220 . Valve operator  230  can also include connecting portion  234 . 
   To install valve  200  in tool  10 , valve operator  230  can be first installed by inserting it through second passage  100  so that operator  230  can be accessible through opening  232 . Next, valve  200  can be installed by inserting valve cannister  242  (such as by sliding) through second passage  100  so that valve ball  220  operatively engages operator  230  through a sliding connection. Locking segment set  268  can be used to lock valve  200  in place. Valve  200  can be completely enclosed in second passage  100 . Valve  200  can be a commercially available cartridge valve, such as that available from M&amp;M international, P.O. Box 10091, New Iberia, La. 70562 (Telephone number (337)-364-4145). With tool  10  second passage  100  can operate as the housing for the cartridge assembly regarding valve  200 . 
   When closed valve  200  fluidly seals upper portion  110  in relation to lower portion  120 . Cap  300  can be used to fluidly seal upper portion  110  in relation to the environment. Valve  200  can include an upper sealing ring  202  (not shown), such as an o-ring or other seal (or even threads). It can also include a lower sealing ring  284 , such as an o-ring or other seal (or even threads). Operator  230  can include a sealing ring  280 , such as an o-ring or other seal (or even threads). Upper and lower sealing rings  202 , 284  along with sealing ring  280  can seal valve  200  relative to second passage  100 . 
   In use tool  10  can be placed in a drill string for an oil and gas well. At bottom  70  of lower body  50  can be threaded using API threading. At top  60  of upper body  40  can also be threaded using API threading. Preferably, a pin end connection is provided at lower body  50  and a box end connection is provided at upper body  40 . 
   In operation (e.g., where tool  10  is connected to a drill string) and it is desired to drop an object (such as ball  400 ) into the drill string the following procedure can be used. Valve  200  is closed thereby sealing off upper portion  110  from lower portion  120 . Vent control  160  can be used to relieve pressure (through vent line  150 ) in upper portion  110 . Cap  300  can be opened and the desired object (e.g., ball  400 ) placed in upper portion  110  above valve  200 . Cap  300  can be placed back sealing off upper portion  110 . Vent control  160  can be closed. When desired valve  200  can be opened and the object (e.g., ball  400 ) will drop in the direction of arrow  102  by action of gravity and/or assisted by a venturi effect of any fluid flow in the direction of arrow  102 . When reaching main passage  80  the desired object will continue to drop, but now in the direction of arrow  85 . 
   Shown in  FIG. 7 , in an alternative embodiment, a by-pass  500  is provided. By-pass  500  can by-pass seal  198  (e.g., valve  200 ) and fluidly connect upper portion  110  with lower portion  120  notwithstanding the closed condition of valve  200 . Such may be necessary where there exists high pressure in main passage  80 . Such high pressure will create a resultant force on the valve ball of valve  200  which may require excessive force to overcome when opening valve  200 . Where valve  540  (e.g., equalizing control  180 ) is opened, fluid can flow from lower portion  120  via by-pass  500  (or equalizing line  170 , which can include lower line  178  and upper line  174 ) in the direction of arrows  510 ,  520 ,  530  to upper portion  110  until pressure in upper portion  110  is equal to pressure in lower portion  120 . Where the pressure is equalized no net resultant force will be found on the valve ball of valve  200  and such valve  200  can be opened easily. Because of machining conditions lower line  178  can be sealed with respect to the outside with plug  177  (via lower opening  176 ) and upper line  174  can be sealed with respect to the outside with plug  173  (via upper opening  172 ). 
     FIGS. 10 through 13  show one embodiment of an equalizing control. Equalizing control  180  can be a needle or plug valve assembly. Equalizing control can comprise cartridge body  182 , bonnet  190 , valve stem  192 , tip  196 , and seat  185 . Cartridge body  182  can comprise inlet passage  184 , seat  185 , radial port  186 , perimeter recess  187 , along with upper and lower o-rings  188 ,  189 . Valve stem  192  can comprise handle  194  and tip  196 . Locking nut  183  can be used to hold in place cartridge body  182 . Bonnet  190  can be threadably connected to valve stem  192 , such that handle  194  can turn stem  192  causing stem  192  to raise or lower depending on the direction of turning of handle  194 . Valve stem  192  can include tip  196  which can be a needle or plug type tip. When equalizing control  180  is in a closed state, tip  196  of stem  192  seals with respect to seat  185  and/or inlet passage  184 . When equaling control  180  is in an open state, tip  196  is not sealed with respect to seat  185  and/or inlet passage  184 . Fluid can flow through inlet passage  184  and into radial port  186 , and finally through perimeter recess  187  to move through lines as described in the immediately preceding paragraph. 
     FIG. 14  shows one embodiment of cap  300 . Cap  300  can comprise top  302 , open area  303  of base of cap (for holding ball  400  or item to be dropped); lanyard tab  304 , right retainer  306 , left retainer  307 , o-ring  308 , and lanyard  310 . 
   In an alternative embodiment, one or more additional second passages  100 ′,  100 ″,  100 ″′, etc. can be provided in enlarged portion  35  which are also fluidly connected to main passage  80 . This can allow multiple dropping activities in a relatively short period of time.  FIG. 8A  is an exploded perspective view of an alternative tool  10 ′ having multiple second passages (e.g.,  100 ,  100 ′), which can assist in the quick or simultaneous dropping of multiple objects (e.g.,  400 ,  400 ′).  FIG. 8B  is an exploded perspective view of another alternative tool  10 ″ having four second passages (e.g.,  100 ,  100 ′,  100 ″,  100 ″′), which can assist in the quick or simultaneous dropping of multiple objects (e.g., balls  400 ,  400 ′,  400 ″,  400 ″′) 
   In an alternative embodiment, first ball  400  and second ball  400 ′ can have the same or different diameters. In another alternative embodiment, first ball  400 , second ball  400 ′, third ball  400 ″, and fourth ball  400 ″′ can have the same or different diameters. Ball sizes are determined by the use of the balls when they are dropped down the tubing or casing string into the well. Depending upon the number of balls it is necessary to drop into the well, the same or different sizes can be used. 
   Operation 
   Tool  10  can be connected to tubing or casing string. All appropriate piping and hose connections can be made, after which tool  10  is ready for use. Ball  400  may or may not be loaded in tool  10  at the time tool  10  is connected to tubing or casing string. If ball  400  is loaded after tool  10  is connected to tubing or casing string then preferably valve  200  is in a closed state. Valve  200  being in a closed state is necessary when tubing or casing string is pressurized at the time ball  400  is loaded into tool  10 . In one embodiment ball  400  can be pre-loaded in tool  10  (i.e., loaded before the time tool  10  is connected to tubing or casing string). 
   When it is desired to drop a first ball  400  into the well, valve  200  is opened by activating valve operator  230 . In one embodiment valve operator  230  can be automatically activated (such as by hydraulic or pneumatic pressure). Activating valve operator  230  will cause valve  200  to enter an open state allowing gravity to pull ball  400  in the direction of arrow  102  (when in second passage  100 ). When ball  400  enters main passage  80  it will move in the direction of arrow  85 . If fluid is flowing in main passage  80  in the direction of arrow  85 , then a venturi effect will assist movement of ball  400  in second passage  100  (in the direction of arrow  102 ). From main passage  80  ball  400  will continue a downward movement in tubing or casing until it eventually contacts a downhole item. 
   When it is desired to drop second ball  400 ′, valve operator  230  can be deactivated causing it to close valve  200  thereby sealing upper portion  110  of second passage  100 . After sealing the upper portion, vent control  160  can be activated to cause vent line  150  to open and release any net gauge pressure from upper portion  10 . If no net gauge pressure exists in second passage  100 , then second passage  100  does not have to be vented. Once pressure is released from the upper portion  110  of second passage  100 , cap  300  can be removed and second ball  400 ′ can be placed in upper portion  110  of second passage  100 . Cap  300  can then be connected to upper portion  110  thereby fluidly sealing upper portion  100  from the outside. Vent line  150  should be checked to make sure it is closed. At this point to drop second ball  400 ′ the same steps as described in the immediately preceding paragraph should be followed. 
   Although a hydraulic or pneumatic remote control actuation of valve  200  has been described, other means of activation can be used. For example, but not by way of limitation, manually activated valve  200  can be performed when desired using a driver or valve  200  can be rotated by a screw driven by an electric motor. 
   The following is a list of reference numerals: 
   
     
       
             
           
             
             
           
             
             
           
         
             
                 
             
             
               LIST FOR REFERENCE NUMERALS 
             
           
        
         
             
               (Reference No.) 
               (Description) 
             
             
                 
             
           
        
         
             
               10 
               tool 
             
             
               20 
               body 
             
             
               30 
               main body 
             
             
               35 
               enlarged section 
             
             
               40 
               upper body 
             
             
               42 
               rounded portion 
             
             
               50 
               lower body 
             
             
               60 
               top 
             
             
               70 
               bottom 
             
             
               80 
               main passage 
             
             
               85 
               arrow 
             
             
               90 
               connection between main and second passage 
             
             
               100 
               second passage 
             
             
               102 
               arrow 
             
             
               110 
               upper portion 
             
             
               120 
               lower portion 
             
             
               150 
               vent line 
             
             
               152 
               vent opening 
             
             
               160 
               vent control 
             
             
               170 
               equalizing line 
             
             
               172 
               upper opening 
             
             
               173 
               plug 
             
             
               174 
               upper line 
             
             
               176 
               lower opening 
             
             
               177 
               plug 
             
             
               178 
               lower line 
             
             
               180 
               equalizing control 
             
             
               181 
               snap ring 
             
             
               182 
               cartridge body 
             
             
               183 
               locking nut 
             
             
               184 
               inlet passage 
             
             
               185 
               seat 
             
             
               186 
               radial port 
             
             
               187 
               perimeter recess 
             
             
               188 
               upper o-ring 
             
             
               189 
               lower o-ring 
             
             
               190 
               bonnet 
             
             
               192 
               valve stem 
             
             
               194 
               handle 
             
             
               196 
               tip 
             
             
               197 
               pin 
             
             
               198 
               seal 
             
             
               200 
               valve 
             
             
               202 
               upper sealing ring 
             
             
               220 
               valve ball 
             
             
               230 
               valve operator 
             
             
               232 
               opening 
             
             
               234 
               connecting portion 
             
             
               242 
               cage or cannister 
             
             
               244 
               spring 
             
             
               248 
               lower seat and teflon 
             
             
               252 
               stem link 
             
             
               256 
               upper seat and teflon 
             
             
               257 
               cage/seat fastener 
             
             
               258 
               lower seat poly seal 
             
             
               259 
               upper and lower seat teflon ring 
             
             
               260 
               stem 
             
             
               264 
               stem bearing assembly 
             
             
               268 
               locking segment set 
             
             
               272 
               support ring 
             
             
               276 
               spiral retainer ring 
             
             
               280 
               upper seat o-ring 
             
             
               282 
               upper seat backup ring 
             
             
               284 
               cannister o-ring 
             
             
               288 
               stem o-ring 
             
             
               292 
               stem back up ring 
             
             
               300 
               cap 
             
             
               302 
               top 
             
             
               303 
               open area of base of cap (for holding ball or item 
             
             
                 
               to be dropped). 
             
             
               304 
               lanyard tab 
             
             
               306 
               right retainer 
             
             
               307 
               left retainer 
             
             
               308 
               o-ring 
             
             
               310 
               lanyard 
             
             
               400 
               ball 
             
             
               500 
               by-pass passage 
             
             
               510 
               arrow 
             
             
               520 
               arrow 
             
             
               530 
               arrow 
             
             
               540 
               valve 
             
             
                 
             
           
        
       
     
   
   It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above. Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention set forth in the appended claims. The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims.