Seal elements for annular control devices

Abstract

A seal element for an annular control device includes an elastomer seal sleeve having an annular opening therein and arranged to be radially compressed to contact an exterior of a pipe disposed within the elastomer seal element. The elastomer seal sleeve comprises at least one of a wear resistant material disposed on an interior surface of the annular opening and a lubricant channel on the interior surface.

What is claimed is: 
     
         1 . A seal element for an annular control device, comprising:
 an elastomer seal sleeve having an annular opening therein and arranged to be radially compressed to contact an exterior of a pipe disposed within the elastomer seal element;   wherein the elastomer seal sleeve comprises at least one of a wear resistant material disposed on an interior surface of the annular opening and a lubricant channel on the interior surface.   
     
     
         2 . The seal element of  claim 1  wherein the wear resistant material comprises longitudinally oriented wear bars. 
     
     
         3 . The seal element of  claim 1  wherein the wear resistant material comprises at least one circumferentially oriented wear ring. 
     
     
         4 . The seal element of  claim 1  wherein the lubricant channel comprises recesses forming a fluid bearing. 
     
     
         5 . The seal element of  claim 1  wherein the lubricant channel comprises at least one helical groove. 
     
     
         6 . The seal element of  claim 1  wherein the lubricant channel comprises an asymmetrical cross section. 
     
     
         7 . The seal element of  claim 6  comprising a taper on one side of the cross section. 
     
     
         8 . The seal element of  claim 1  wherein the interior surface comprises a sawtooth shape. 
     
     
         9 . The seal element of  claim 1  further comprising a wiper seal disposed on at least one longitudinal end of the seal sleeve. 
     
     
         10 . The seal element of  claim 1  wherein the interior surface is shaped in the form of a labyrinth seal arranged to distribute a differential pressure across the seal element through a plurality of labyrinth chambers. 
     
     
         11 . The seal element of  claim 1  wherein a pitch of the lubricant channel is selected to provide maximized fluid lift with respect to effective linear speed between the exterior surface of the pipe and the interior surface of the annular opening. 
     
     
         12 . The seal element of  claim 1  wherein the elastomer seal material comprises at least one sensor. 
     
     
         13 . The seal element of  claim 12  wherein the at least one sensor comprises a resistance sensor formed from material chosen to wear at a rate related to wear of the elastomer seal material. 
     
     
         14 . The seal element of  claim 12  wherein the at least one sensor comprises a temperature sensor.