Abstract:
The present invention generally relates to a valve for use in an oilfield tool. The valve includes a valve body and a valve member disposed in the valve body. The valve member is movable between an open and closed position. The valve member includes an aperture therethrough. The valve further includes a pressure relief member disposed in the aperture, whereby at a predetermined pressure the pressure relief member will permit fluid communication. In another aspect, the invention provides an apparatus and a method for introducing fluid into a tubular.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to an apparatus and a method used in the completion of a well. More particularly, the invention relates to a casing fill-up and circulating tool. More particularly still, the present invention relates to a diaphragm ball valve for a casing fill-up and circulating tool.  
           [0003]    2. Description of the Related Art  
           [0004]    In the drilling of oil and gas wells, a wellbore is formed using a drill bit that is urged downwardly at a lower end of a drill string. After drilling the wellbore to a predetermined depth, the drill string and bit are removed. Thereafter, the wellbore is typically lined with a string of steel pipe called casing. The casing provides support to the wellbore and facilitates the isolation of certain areas of the wellbore adjacent hydrocarbon bearing formations.  
           [0005]    During the run-in of a casing string, the string is typically filled with mud. The primary reason to fill the casing string with mud is to prevent the new string of casing from collapsing due to the pressure imbalances between the inside of the casing and the wellbore fluid therearound and avoidance of buoyancy. Typically, the filling process occurs as the casing string is assembled at the rig floor. A secondary reason to fill a casing string with mud is to use the mud to free a casing string when the casing becomes stuck during the run-in operation. In this situation, the drilling operator circulates mud down the casing to wash sand or other debris from the lowermost end of the casing, thereby freeing the stuck casing.  
           [0006]    Typically, a fill-up and circulating tool is used in conjunction with a mud pump to fill and circulate the mud in the casing. An example of a fill-up and circulating tool is described in U.S. Pat. No. 6,173,777, which is incorporated herein by reference in its entirety. FIG. 1 illustrates a partial cross-sectional view of a fill-up and circulating tool  50  with a valve  60  in a closed position as shown in the &#39;777 patent. The tool  50  is supported from a top drive (not shown) and includes a top sub  10  with an internal bore  12 . The internal bore  12  is connected to a mud pump (not shown) through a hose (not shown) for filling and circulating a casing  14 . The top sub  10  is connected to body  16  at thread  18 . Tool  50  further includes a rotating sleeve  22  disposed on the upper portion of the body  16 . A cup seal  20  is mounted to sleeve  22 . The cup seal  20  is used to seal off the casing  14  when the tool  50  is operating. Additionally, a gage ring  38  is mounted on body  16  and secured in place by nut  34 . The gage ring  38  positions the tool  50  in the center of the casing  14  to facilitate insertion of the tool  50  into the upper end of the casing  14 .  
           [0007]    As shown in FIG. 1, the body  16  is connected to the valve  60  through a tubular spacer  35 . The valve  60  includes a valve member  41  (ball valve) that is movable between an open and closed position. The valve member  41  is disposed in a valve body  40 . The valve member  41  is held in position within the valve body  40  by an upper valve seal  42 , lower valve seal  43 , and bottom sub  45 . A valve stem  46  and an arm  44  are attached to valve member  41  to control the open/closed rotational position of the valve member  41 . As shown, a gage ring  53  is disposed at the lower end of the valve body  40 . The gage ring  53  centers the valve  60  in the casing and protects valve arm  44  during insertion of the valve  60  into the upper end of the casing  14 . Centering of the valve  60  ensures that the arm  44  will rotate sufficiently to open the valve member  41 . In the closed position, the arm  44  is rotationally limited by its contact with gage ring  53 . The arm  44  is constructed and arranged of weighted material to open the valve member  41  only when the valve  60  is inserted into casing  14  and to close the valve member  41  after the valve is removed from the casing  14 . The arm  44  is weighted such that upon removal, gravity causes the arm  44  to rotate downward, thereby providing rotational torque to close the valve member  41  as the valve  60  is removed from the casing  14 .  
           [0008]    [0008]FIG. 2 illustrates a partial cross-sectional view of the prior art fill-up and circulating tool  50  with the valve  60  in an open position as shown in the &#39;777 patent. As depicted, the valve  60  is fully inserted into the upper end of the casing  14 . As the valve  50  is inserted, the bottom sub  45  will be positioned near the center of the casing  14  and gage ring  53  will further center the valve  60 . At the same time, the valve arm  44  will be rotated by contact with the upper end of the casing  14 . Rotating the valve arm  44  upwards opens valve member  41 . In this position, a mud pump may be started to fill the casing  14 . Fluid from the pump flows through the bore  12 , through the fully opened valve member  41  and out ports  47  to fill the casing  14 . After the casing  14  is filled, the mud pump is turned off and the tool  50  may be removed from the casing  14 . Upon removal of the valve  60 , gravity causes the weighted arm  44  to rotate downward, thereby rotating the valve member  41  to the closed position as shown on FIG. 1. In this manner, the casing  14  is filled with mud.  
           [0009]    Generally, the mud pump is turned off while the fill-up and circulating tool is still in the casing, thereby allowing all the mud in the mud pump and the connecting hose to flow through the tool into the casing. However, a problem associated with the above referenced fill-up and circulating tool arises when the tool is suddenly or accidentally removed from the casing prior to shutting down of the mud pump. In this situation, a pressure surge is created in the tool due to the closed valve, thereby causing the mud pump to stop. This pressure surge may cause premature failure of the mud pump or other hydraulic components. Another problem arises after the casing is filled with mud. Typically, the tool is pulled out of the casing and the valve arm drops down to close the valve member. However, if the mud pump is not properly turned off to allow the mud in the in the connecting hose to exit the tool prior to removal of the tool from the casing, the volume of mud continues to enter the tool. Because the valve member is closed, the mud is prevented from exiting the tool. As a result, the pressure in the tool may become so large as to cause the hose to burst, thereby causing damage to the equipment or injury to personnel on the rig floor.  
           [0010]    There is a need, therefore, for a valve that will prevent a pressure surge in the mud system when the tool is accidentally removed from the casing. There is a further need for a valve that will permit a volume of mud in the hose to exit the tool even though the valve is closed. There is yet a further need for a more reliable fill-up and circulating tool.  
         SUMMARY OF THE INVENTION  
         [0011]    The present invention generally relates to a valve for use in an oilfield tool. The valve includes a valve body and a valve member disposed in the valve body. The valve member is movable between an open and closed position. The valve member includes an aperture therethrough. The valve further includes a pressure relief member disposed in the aperture, whereby at a predetermined pressure the pressure relief member will permit fluid communication.  
           [0012]    In another aspect, the invention provides an apparatus to introduce fluid into a casing. The apparatus includes a body having a bore therethrough and a valve disposed in the body for selectively controlling a fluid flow through the bore. The valve includes a valve member movable between an open and closed position. The valve member includes an aperture for providing selective communication through the valve in a closed position. The valve further includes a pressure relief member disposed in the aperture, whereby at a predetermined pressure the pressure relief member will permit fluid communication.  
           [0013]    Further, a method for introducing fluid into a tubular is provided. The method includes the step of locating an apparatus in the tubular. The apparatus includes a body having a bore therethrough and a valve disposed in the body for selectively controlling a flow fluid through the bore. The valve includes a valve member and a pressure relief member disposed in the valve member. The method further includes opening the valve in the apparatus, pumping fluid through the apparatus, and introducing fluid in to the tubular. The method also includes the step of removing the apparatus from the tubular.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    So that the manner in which the above recited features of the present invention, and other features contemplated and claimed herein, are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.  
         [0015]    [0015]FIG. 1 illustrates a partial cross-sectional view of the prior art fill-up and circulating tool of the &#39;777 patent with a valve in a closed position.  
         [0016]    [0016]FIG. 2 illustrates a partial cross-sectional view of the prior art fill-up and circulating tool of the &#39;777 patent with the valve in an open position.  
         [0017]    [0017]FIG. 3 illustrates a valve member of the present invention disposed in an oilfield tool.  
         [0018]    [0018]FIG. 4 is an enlarged view of the valve member in an open position.  
         [0019]    [0019]FIG. 5 illustrates an enlarged view of the valve member in a closed position.  
         [0020]    [0020]FIG. 6 illustrates a view of the valve member after the frangible disk member fails. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0021]    [0021]FIG. 3 illustrates a valve member  100  of the present invention disposed in an oilfield tool. As illustrated, the oilfield tool is a fill-up and circulating tool  200 . However, it should be noted that the valve member  100  may also be employed in other hydraulic oilfield tools that require a valve that will prevent premature failure of hydraulic components due to pressure surges and pressurization of the tool, thereby ensuring the safety of equipment and personnel.  
         [0022]    As shown in FIG. 3, the tool  200  includes a body  160  that comprises of an upper body  140  and a lower body  180 . The upper body  140  having an upper bore  145  to allow fluid communication through the tool  200 . Typically, the top portion of the upper body  140  is connected to a mud pump (not shown). The mud pump is used for pumping the mud through the tool  200  into a casing string (not shown). The mud pump is typically connected to the tool  200  using a hydraulic hose (not shown).  
         [0023]    As illustrated, the lower body  180  is disposed below the upper body  140 . The lower body  180  contains a lower bore  175  in fluid communication with the upper bore  145 . The lower bore  175  diverges into one or more ports  185  at the lower end of the body  180 . Additionally, a gage ring  170  is disposed around the lower body  180  to center the tool  200  in the casing string.  
         [0024]    As depicted on FIG. 3, the valve member  100  is disposed between the upper body  140  and lower body  180 . The valve member  100  is housed in a valve body  110 . The valve body  110  is connected to the lower end of the upper body  140 . First and second seal members  120 ,  125  are disposed between the upper body  140  and the valve body  110 . The first and second seal members  120 ,  125  form a sealing relationship between the upper body  140  and the valve body  110  to prevent fluid in the upper bore  145  from flowing around the valve body  110 .  
         [0025]    In the preferred embodiment, the valve member  100  is a standard ball valve. However, other forms of valve members may be employed, so long as they are capable of selectively permitting fluid flow through the tool  200 . Additionally, in the preferred embodiment, the valve member  100  is constructed from stainless steel. However, the valve member  100  may also be constructed from other types of materials, such as composite material, so long as it is capable of withstanding a predetermined pressure and wellbore fluids that may be corrosive.  
         [0026]    The valve member  100  is movable between an open and a closed position. Generally, the open position permits fluid to enter and exit the tool  200  while the closed position prevents fluid from exiting the tool  200  by sealing a valve bore  115 . In the open position, the valve bore  115  in the valve member  100  aligns with the upper bore  145  and the lower bore  175 , thereby allowing fluid communication through the tool  200 . Conversely, in the closed position, the valve member  100  is rotated approximately 90 degrees. As a result, the valve bore  115  is out of alignment with the bores  145 ,  175 , thereby preventing the flow of fluid through the valve bore  115 . In this manner, the valve member  100  selectively controls fluid communication through the tool  200 .  
         [0027]    The valve member  100  further includes an aperture or a lateral bore  195  therethrough to act as a fluid conduit. A pressure relief member or a frangible disk member  105  is disposed in the lateral bore  195  to temporality prevent fluid communication through the lateral bore  195 . As shown, the lateral bore  195  is located perpendicular to the valve bore  115 . Therefore, as the valve member  100  is moved to the closed position, the lateral bore  115  aligns with the upper bore  145  and the lower bore  175 . However, the presence of the frangible disk member  105  prevents fluid communication between the upper bore  145  and the lower bore  175 .  
         [0028]    The frangible disk member  105  is a high-precision component designed to fail with the application of a predetermined hydraulic pressure. Typically, the frangible disk member  105  is a rupture disk or a diaphragm. Rupture disks are commonly used in downhole applications in which the controlled application of pump pressure is used to set or operate downhole equipment. In the present invention, the frangible disk member is used as a protection device to prevent pressurization of the tool  200 . In doing so the frangible disk member  105  allows fluid communication between the upper bore  145  and the lower bore  175  when the frangible disk member  105  fails due to a pressure above the predetermined hydraulic pressure.  
         [0029]    The tool  200  further includes a valve stem  130  connected to the valve member  100 . As shown, an arm  135  and a handle  155  are connected to the valve stem  130  on the exterior of the tool  200 . The handle  155  is constructed and arranged of weighted material to open the valve member  100  only when the tool  200  is inserted into casing and to close the valve member  100  after the tool  200  is removed from the casing. The handle  155  is weighted such that upon removal from the casing, gravity causes the handle  155  and arm  135  to rotate downward, thereby providing rotational torque to close the valve member  100 . In this manner the handle  155 , arm  135  and valve stem  130  act as a unit to cause the valve member  100  to move between the open and closed position during operation of the tool  200 .  
         [0030]    [0030]FIG. 4 is an enlarged view of the valve member  100  in the open position. As shown, the valve bore  115  in the valve member  100  is aligned with the upper bore  145  and the lower bore  175 . As illustrated by arrow  205 , fluid from the mud pump is permitted to flow down the upper bore  145 , through the valve bore  115  and into the lower bore  175 . As further shown, the first and second seal members  120 ,  125  on the valve body  110  prevent any fluid from entering around the valve body  110 . Also clearly shown is the frangible disk member  105  disposed in the lateral bore  195 . It should be noted that the valve member  100  in the open position does not expose frangible disk member  105  to the flow of fluid through the valve bore  115 .  
         [0031]    [0031]FIG. 5 illustrates a view of the valve member  100  in the closed position. As depicted, the valve member  100  has rotated approximately 90 degrees to the closed position. The valve bore  115  is no longer aligned with the upper bore  145  and the lower bore  175 . Instead, the lateral bore  195  is aligned with the upper bore  145  and lower bore  175 , thereby exposing the frangible disk member  105  to the fluid in the upper bore  145 . As illustrated by the flow arrow  205 , the fluid in the upper bore  145  is prevented from entering the lower bore  175 . In addition, the sealing relationship between the valve body  110  and the upper body  140  prevents any leakage around the first and second seal members  120 ,  125 .  
         [0032]    Typically, the mud pump will be turned off prior to moving the valve member  100  to the closed position as shown on FIG. 5. The excess fluid in the hose connecting the mud pump to the tool  200  will either stay in the hose or flow to the tool  200 . Fluid in the tool  200  will usually be at a low pressure because there is no additional fluid pressure from mud pump. In this respect, the hydraulic pressure acting against the frangible disk member  105  is below the predetermined hydraulic pressure, thereby allowing the frangible disk member  105  to act as a barrier to fluid communication into the lower bore  175 . Therefore, fluid will collect in the upper bore  145  and remain there until the valve member  100  is opened. At that time, the valve bore  115  will align with the upper bore  145 , thereby allowing the fluid to be communicated to the lower bore  175 .  
         [0033]    However, if the valve member  100  is intentionally or accidentally closed while a volume of mud in the hose continues to be communicated to the tool  200 , a pressure build up will occur in the upper bore  145 . As more fluid enters the upper bore  145 , the hydraulic pressure acting against the frangible disk member  105  will increase. At a predetermined hydraulic pressure, the frangible disk member  105  is caused to fail, thereby allowing fluid to enter the lower bore  175  as illustrated in FIG. 6.  
         [0034]    [0034]FIG. 6 illustrates a view of the valve member  100  after the frangible disk member  105  fails. As shown, the frangible disk member  105  is no longer disposed within the lateral bore  195  but rather is destroyed, thereby removing the barrier between the upper bore  145  and the lower bore  175 . As illustrated by arrow  205 , the pressurized fluid inside the upper bore  145  is allowed to flow through the lateral bore  195  into the lower bore  175  exiting the tool  200  through port  185 . In this manner, the pressure in the upper bore  145  of the tool  200  may be relieved to prevent damage to the hose or the mud pump.  
         [0035]    According to another important aspect of the present invention, the destroyed frangible disk member  105  may be replaced without replacing the valve member  100 . In this respect, the valve member  100  may be removed from the valve body  110  to permit the replacement of the frangible disk member  105 . The destroyed frangible disk member  105  is removed and a new frangible disk member  105  is disposed in lateral bore  195 . Thereafter, the original valve member  100  and the new frangible disk member  105  are placed back into the valve body  110 . In this manner, the tool  200  may be quickly put back into operation to continue to fill and circulate mud through the casing string.  
         [0036]    In operation, the tool  200  is inserted into a string of casing. Upon installation, the handle  155  is caused to contact the string of casing and move the valve member  100  from the closed position to the open position. Thereafter, the mud pump is turned on to introduce fluid into the tool  200  to fill the casing with mud. The fluid flows down the upper bore  145 , through the valve bore  115  and the lower bore  175 , thereafter exiting out port  185 . After the casing is filled, the mud pump is turned off and the tool  200  is removed from the casing. Upon removal of the tool  200 , gravity causes the weighted handle  155  to rotate downward, thereby returning the valve member  100  to the closed position.  
         [0037]    In the event that the tool  200  is removed from the casing prematurely, the valve member  100  will close. At this point, fluid will gather in the upper bore  145 . As more fluid enters the upper bore  145 , the hydraulic pressure acting against the frangible disk member  105  will increase. At a predetermined hydraulic pressure, the frangible disk member  105  is caused to fail, thereby allowing fluid to flow through the lateral bore  195 . Thereafter, the pressurized fluid inside the upper bore  145  is permitted to flow through the lateral bore  195  into the lower bore  175  exiting the tool  200  through port  185 . In this manner, the pressure in the upper bore  145  of the tool  200  may be relieved to prevent damage to the hose or the mud pump.  
         [0038]    While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.