| Patent Number |
Title Of Patent |
Date Issued |
| 7395877 |
Apparatus and method to reduce fluid pressure in a wellbore |
July 8, 2008 |
| The present invention generally provides apparatus and methods for reducing the pressure of a circulating fluid in a wellbore. In one aspect of the invention an ECD (equivalent circulation density) reduction tool provides a means for drilling extended reach deep (ERD) wells with heav |
| 7111692 |
Apparatus and method to reduce fluid pressure in a wellbore |
September 26, 2006 |
| The present invention generally provides apparatus and methods for reducing the pressure of a circulating fluid in a wellbore. In one aspect of the invention an ECD (equivalent circulation density) reduction tool provides a means for drilling extended reach deep (ERD) wells with heav |
| 7066247 |
Methods and apparatus for drilling with a multiphase pump |
June 27, 2006 |
| The present invention generally relates to an apparatus and method for removing hydrocarbons and other material from a wellbore. In one aspect, a method of drilling a sub-sea wellbore is provided. The method includes circulating a drilling fluid through a drill string from a surface of t |
| 6966367 |
Methods and apparatus for drilling with a multiphase pump |
November 22, 2005 |
| The present invention generally relates to an apparatus and method for removing hydrocarbons and other material from a wellbore. In one aspect, a method of drilling a sub-sea wellbore is provided. The method includes circulating a drilling fluid through a drill string from a surface of t |
| 6837313 |
Apparatus and method to reduce fluid pressure in a wellbore |
January 4, 2005 |
| The present invention generally provides apparatus and methods for reducing the pressure of a circulating fluid in a wellbore. In one aspect of the invention an ECD (equivalent circulation density) reduction tool provides a means for drilling extended reach deep (ERD) wells with heavywei |
| 5636661 |
Self-piloting check valve |
June 10, 1997 |
| A check valve 200 has an elongate cylindrical tubular body 202 which provides mounting for a main flap valve 204. Mounted below the main valve 204 is a smaller multi-leaf flap valve 206. The smaller valve 206 is mounted on a housing 208 which is axially movable relative to the body 2 |
