Adjustable tubular slip

Abstract

In an example, a tubular slip for a drill rig can include a plurality of size adjusting systems which can be radially arranged about a well access hole of the drill rig and can be configured to cooperate to adjust a diameter of a through opening of the tubular slip to accommodate various tubular sizes. The tubular slip can also include a slip component which can include a wedge arranged on a radially inner portion of each of the size adjusting systems and can be configured to cooperate to further constrict the diameter of the through opening when a drill string is suspended by the tubular slip.

What is claimed is: 
     
         1 . A tubular slip for a drill rig, comprising:
 a plurality of size adjusting systems radially arranged about a well access hole of the drill rig and configured to cooperate to adjust a diameter of a through opening of the tubular slip to accommodate various tubular sizes;   a slip component comprising a wedge arranged on a radially inner portion of each of the size adjusting systems and configured to cooperate to further constrict the diameter of the through opening when a drill string is suspended by the tubular slip.   
     
     
         2 . The tubular slip of  claim 1 , wherein each of the plurality of size adjusting systems are configured to travel between a retracted position, wherein the respective slip components are not contacting the drill string, and an engaged position, wherein the respective slip components are contacting the drill string. 
     
     
         3 . The tubular slip of  claim 2 , wherein the movement of the size adjusting systems serves the function of both:
 engaging and disengaging the drill string; and   accommodating various tubular sizes.   
     
     
         4 . The tubular slip of  claim 2 , comprising a guide, configured to receive the drill string generally centered along a center axis of the well access hole, wherein the guide is configured to prevent the drill string from contacting the slip components when the size adjusting systems are in the retracted position. 
     
     
         5 . The tubular slip of  claim 1 , wherein a radially inner surface of the slip component is configured to engage with the drill string, wherein the tubular slip is configured to engage with a range of tubular sizes spanning at least 4 inches. 
     
     
         6 . The tubular slip of  claim 5 , wherein the radially inner surface of the slip component is configured to be generally parallel to the drill string across the range of tubular sizes. 
     
     
         7 . The tubular slip of  claim 1 , comprising a housing, wherein a radially outer portion of the housing is configured to engage with a portion of a drill floor of the drill rig defining the well access hole, wherein a radially inner portion of the housing is configured to engage with a radially outer portion of the size adjusting systems. 
     
     
         8 . The tubular slip of  claim 1 , further comprising the drill rig, the drill rig comprising:
 a drill floor supported by a support structure, wherein the tubular slip is arranged on the drill floor.   
     
     
         9 . A tubular slip for a drill rig, the tubular slip comprising:
 two or more slip assemblies, arranged around a perimeter of a well access hole of the drill rig, each of the slip assemblies including:
 an outer wedge, generally fixed relative to the well access hole, wherein a radially inward portion of the outer wedge includes a first inclined plane facing radially inward, wherein a bottom portion of the first inclined plane is radially inward compared to a top portion of the first inclined plane; 
 an intermediate wedge, wherein a radially outward portion of the intermediate wedge is slidably engaged with the first inclined plane, wherein the intermediate wedge moves towards a center axis of the well access hole when the intermediate wedge slides downward, wherein a radially inward portion of the intermediate wedge includes a second inclined plane facing radially inward, wherein a bottom portion of the second inclined plane is radially inward compared to a top portion of the second inclined plane; and 
 an inner wedge, wherein a radially outward portion of the inner wedge is slidably engaged with the second inclined plane, wherein the inner wedge moves towards the center axis of the well access hole when the inner wedge slides downward. 
   
     
     
         10 . The tubular slip of  claim 9 , wherein the slip assemblies comprise an actuator, wherein a first end of the actuator is coupled to the outer wedge and a second end of the actuator is coupled to the intermediate wedge, wherein the actuator is configured to control a position of the intermediate wedge along the first inclined plane between a retracted position, wherein the slip assembly is not contacting a drill string, to an engaged position, wherein the slip assembly is contacting the drill string. 
     
     
         11 . The tubular slip of  claim 10 , comprising a spring element, configured to bias the inner wedge in an upward direction along the second inclined plane. 
     
     
         12 . The tubular slip of  claim 9 , wherein a second angle of the second inclined plane relative to the center axis of the well access hole is less than a first angle of the first inclined plane relative to the center axis of the well access hole. 
     
     
         13 . The tubular slip of  claim 12 , wherein the second angle is between 9 and 14 degrees and wherein the first angle is between 14 and 35 degrees. 
     
     
         14 . The tubular slip of  claim 9 , wherein the slip assemblies are configured such that frictional forces acting on the intermediate wedge exceed an upward force caused by differing angles of the first inclined plane and the second inclined plane. 
     
     
         15 . The tubular slip of  claim 9 , wherein being generally fixed relative to the well access hole includes being generally fixed relative to a turntable of the drill rig. 
     
     
         16 . A method of using a tubular slip, the method comprising:
 positioning, using an elevator, a drill string at a specified position within the tubular slip while the tubular slip is in a released configuration;   engaging three slip assemblies of the tubular slip with the drill string;   centering the drill string within a well access hole; and   disengaging the elevator to transfer a weight of the drill string to the tubular slip.   
     
     
         17 . The method of  claim 16 , wherein centering the drill string within the well access hole includes:
 monitoring respective positions of the three slip assemblies; and   adjusting the three slip assemblies so that the drill string is centered within the well access hole.   
     
     
         18 . The method of  claim 17 , wherein monitoring a position of the three slip assemblies includes monitoring respective actuators of the three slip assemblies. 
     
     
         19 . The method of  claim 18 , comprising:
 wherein centering the drill string within the well access hole includes engaging the three slip assemblies so that each of the slip assemblies starts a specified distance from a center axis of the well access hole and travels at a same rate toward the center axis of the well access hole.   
     
     
         20 . The method of  claim 16 , comprising engaging one or more additional slip assemblies following centering the drill string within the well access hole.