Dual bearing rotating control head and method

Abstract

An apparatus comprises a first bearing assembly, a second bearing assembly, a housing and a pipe. The first bearing assembly, the second bearing assembly and the housing define an interior space. The pipe extends through the first bearing assembly and the second bearing assembly and through the interior space.

What is claimed is: 
     
         1 . An apparatus comprising:
 a first bearing assembly;   a second bearing assembly;   a housing, the first bearing assembly, the second bearing assembly and the housing defining an interior space, and   a pipe extending through the first bearing assembly and the second bearing assembly and through the interior space.   
     
     
         2 . The apparatus of  claim 1 , wherein the housing comprises at least one port in fluid communication with the interior space. 
     
     
         3 . The apparatus of  claim 2 , further comprising a main pressure sensor in fluid communication with the interior space. 
     
     
         4 . The apparatus of  claim 2 , further comprising a fluid pump in fluid communication with the interior space. 
     
     
         5 . The apparatus of  claim 4 , further comprising a pressure regulator in fluid communication with the interior space. 
     
     
         6 . The apparatus of  claim 5 , wherein the fluid pump moves a lubricant. 
     
     
         7 . The apparatus of  claim 1 , further comprising a first pressure sensor located exteriorly of the interior space functionally adjacent the first bearing assembly. 
     
     
         8 . The apparatus of  claim 1 , further comprising a second pressure sensor exteriorly of the interior space adjacent the second bearing assembly. 
     
     
         9 . The apparatus of  claim 1 , wherein each of the first bearing assembly and the second bearing assembly comprises a stripper element, the pipe to be accommodated by the stripper elements. 
     
     
         10 . The apparatus of  claim 1 , wherein the apparatus comprises a rotating control head. 
     
     
         11 . A method comprising:
 pressurizing fluid to a predetermined value in an interior space defined by a housing, a first bearing assembly and a second bearing assembly; and   measuring a pressure of the interior space to determine a leak in at least one of the first bearing assembly and the second bearing assembly when the measured pressure differs from the predetermined by a predetermined amount.   
     
     
         12 . The method of  claim 11 , further comprising measuring a pressure from a first pressure sensor located exteriorly of the interior space and adjacent the first bearing assembly to determine a leak in the first bearing assembly. 
     
     
         13 . The method of  claim 11 , further comprising measuring a pressure from a second pressure sensor located exteriorly of the interior space and adjacent the second bearing assembly to determine a leak in the second bearing assembly. 
     
     
         14 . The method of  claim 11 , wherein the fluid comprises a lubricant. 
     
     
         15 . The method of  claim 11 , further comprising replacing at least one of the first bearing assembly and the second bearing assembly. 
     
     
         16 . A method comprising:
 pumping lubricant into an interior space of an apparatus defined by at least a first bearing assembly and a second bearing assembly, each of the first bearing assembly and the second bearing assembly comprising a stripper element; and   inserting a pipe through the interior space so as to go through the first bearing assembly and the second bearing assembly.   
     
     
         17 . The method of  claim 16 , further comprising moving the pipe with respect to the interior space so as to lubricate at least one stripper element. 
     
     
         18 . The method of  claim 17 , wherein moving the pipe in a first direction introduces the lubricant to the stripper element associated with the first bearing assembly. 
     
     
         19 . The method of  claim 17 , wherein moving the pipe in a second direction introduces the lubricant to the stripper element associated with the second bearing assembly. 
     
     
         20 . The method of  claim 17 , wherein the pumping generates a pressure substantially equal to a pressure in an annular space in a wellbore.