METHOD AND APPARATUS FOR HYBRID ELEMENT CASING PACKER FOR CASED-HOLE APPLICATIONS

摘要

The present invention is directed to a new and improved wellbore packing device for use in isolating zones within a subterranean wellbore and to methods for applying the packing device in a cased-hole application. The present invention is directed to a new and improved inflatable or external casing packer (ECP) for us e in cased wellbores. A hybrid inflatable packing element design in an ECP is presen ted, having in a single-unit, anchoring and sealing sections for application in cased wellbores using a phase change inflation medium such as cement or epoxy or the l ike. The present invention overcomes limitations of existing prior art ECP's since th ese prior art ECP's are not capable of providing both sealing and anchoring packing elements in a single unitized design in size and access restricted wellbores. The inflatable elements comprise a sealing section that uses a noncontinuously reinforced elastomeric element with anti-extrusion ribs at its ends. When fille d with the inflation medium, a frictional, radial force sealingly engages the elastomer ic elements with casing wall. An anchoring section is also provided that uses a continuously ribbed elastomeric bladder element. The steel ribs on the surface of the elastomeric element engage in metal-to-metal contact with the casing wall as the inflation medium exerts a frictional, radial force. Any trapped wellbore fluid between the sections escapes via the pathway between the ribs. A method for use of the hybrid ECP is also disclosed. More specifically, a method for use of the hybrid inflat able packer in a cased-hole environment with a phase change inflation media is presen ted.