(12) United States Patent ao) Patent No.: us 6,276,450 Bi
Seneviratne (45) Date of Patent: Aug. 21,2001
(54) APPARATUS AND METHOD FOR RAPID REPLACEMENT OF UPPER BLOWOUT PREVENTERS
(75) Inventor: Padmasiri Daya Seneviratne,
Fullerton, CA (US)
(73) Assignee: Varco International, Inc., Orange, CA (US)
( * ) Notice: Subject to any disclaimer, the term ol this patent is extended or adjusted under 35 U.S.C. 154(b) by 0 days.
(21) Appl. No.: 09/364,747
(22) Filed: Jul. 30, 1999
Related U.S. Application Data
(60) Provisional application No. 60/132,140, filed on May 2, 1999.
(51) Int. CI. E21B 19/00
(52) U.S. CI 166/85.1; 166/85.4; 166/77.52;
(58) Field of Search 166/77.51, 77.52,
166/85.4, 84.3, 85.3, 378, 379, 380; 175/85, 113, 122, 162, 203
(56) References Cited
U.S. PATENT DOCUMENTS
4,449,596 5/1984 Boyadjieff.
Apparatus and method for rapid replacement ol upper inside blowout preventers (IBOP) on a top drive system (TDS) utilizes a hydraulic pressure booster to increase the operating pressure ol a pipe handler/torque wrench, an air amplifier to increase the air pressure to a main shaft brake ol the TDS in order to provide torque back-up, a rotary table back-up structure (RTBS) for providing a torque back-up for removing the upper IBOP, and a drive ring for preventing relative rotation between the RTBS and upper IBOP. The saver sub and lower IBOP are first broken out, or loosened, with the pipe handler/torque wrench. The upper IBOP is then broken out by placing the RTBS over the rotary table with the rotary table and the TDS main shaft locked. The modified TDS and pipe handler/torque wrench are then used together with the RTBS and drive ring in order to rapidly and salely replace the upper IBOP.
20 Claims, 12 Drawing Sheets