Elastomer Material for High Temperature Roller Cone Bits

Abstract

An earth boring bit has a bit body with at least one bearing pin. A cone is rotatably mounted on the bearing pin. A seal assembly is located between the cone and the bearing pin, the seal assembly having at least one flexible seal member. A flexible pressure compensating diaphragm is mounted in the body. The diaphragm has one side adapted to be exposed to borehole fluids and another side in contact with lubricant contained in bearing spaces between the cone and the bearing pin. The flexible seal member and the diaphragm are formed of a fluorinated elastomer. The elastomer is either a perfluoroelastomer (FFKM) or a fluoroelastomer (FKM).

1 . A rotating cone earth boring bit having a plurality of flexible elements therein, and wherein at least one of the flexible elements comprises an elastomer containing fluorine. 
   
   
       2 . The bit according to  claim 1 , wherein the elastomer comprises a perfluoroelastomer (FFKM). 
   
   
       3 . The bit according to  claim 1 , wherein the elastomer comprises a fluoroelastomer (FKM). 
   
   
       4 . The bit according to  claim 1 , wherein said at least one of the flexible elements comprises a seal ring that is at least part of a seal assembly between a cone and a bearing pin. 
   
   
       5 . The bit according to  claim 1 , wherein said at least one of the flexible elements comprises a lubricant pressure compensator diaphragm. 
   
   
       6 . An earth boring bit, comprising:
 a bit body having at least one bearing pin;   a cone rotatably mounted on the bearing pin;   a seal assembly between the cone and the bearing pin, the seal assembly having at least one flexible seal member;   a flexible pressure compensating diaphragm in the body having one side adapted to be exposed to borehole fluids and another side in contact with lubricant contained in bearing spaces between the cone and the bearing pin; and   wherein the flexible seal member and the diaphragm are formed of a fluorinated elastomer.   
   
   
       7 . The bit according to  claim 6 , wherein the elastomer comprises a perfluoroelastomer (FFKM). 
   
   
       8 . The bit according to  claim 6 , wherein the elastomer comprises a fluoroelastomer (FKM). 
   
   
       9 . The bit according to  claim 6 , wherein the seal assembly comprises a dynamic rigid seal ring;
 and wherein said at least one flexible seal member comprises:
 an energizing ring that acts against the rigid seal ring. 
   
   
   
       10 . The bit according to  claim 6 , wherein the seal assembly comprises a rigid seal ring that dynamically engages a rigid insert mounted in and rotating with the cone; and wherein said at least one the flexible seal member comprises:
 an energizing ring deformed between the bit body and the rigid seal ring; and   an excluder ring deformed between the body, the energizing ring and the rigid ring.   
   
   
       11 . An earth boring bit, comprising:
 a bit body having at least one bearing pin;   a cone rotatably mounted on the bearing pin and having a rigid insert mounted therein for rotation therewith;   a rigid ring that engages the rigid insert in sliding and sealing contact;   an energizer ring statically engaging a portion of the bearing pin and the rigid ring and urging the rigid ring into engagement with the rigid insert;   a flexible pressure compensating diaphragm in the body, having one side adapted to be exposed to borehole fluids and another side in contact with lubricant contained in bearing spaces between the cone and the bearing pin; and   wherein the energizer ring and the diaphragm are formed of a fluorinated elastomeric compound.   
   
   
       12 . The bit according to  claim 11 , further comprising:
 an excluder ring statically engaging a portion of the bearing pin, the energizing ring and the rigid ring; and   wherein the excluder ring is formed of a fluorinated elastomeric compound.   
   
   
       13 . The bit according to  claim 11 , wherein the elastomer comprises a perfluoroelastomer (FFKM). 
   
   
       14 . The bit according to  claim 11 , wherein the elastomer comprises a fluoroelastomer (FKM).