Frank Hartley
Drilling & Production Editor
ORLANDO, Florida -- A gas tight, third-generation rotary shoulder connection (RSC) has been developed for 20,000 psi internal and 10,000 psi external pressure service, said Jim Brock with Grant Prideco at the 2008 IADC Drilling Conference today. He said that the ISO13679 testing methods for casing and tubing were modified to evaluate the RSC pressure capability.
Brock said the result of this program is an RSC that incorporates a double-start thread form to reduce the number of revolutions required to assemble the connection by 50%, thereby reducing trip time. He continued to say the thread form provides a unique dual-radius thread root that offers an improvement in fatigue resistance plus a metal-to-metal seal for pressure integrity.
He concluded that in addition to providing a 20,000 psi internal and 10,000 psi external pressure rating, the new connections increased both mechanical and hydraulic performance compared to second-generation, high-torque connections, while providing fatigue performance exceeding standard API connections.
3/4/2008
