Importance

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Abstract

A casing annulus remediation system for overcoming problems associated with lowering a flexible hose into an annulus between strings of casing in a petroleum well by pressurizing the hose so that the hose is rigid and may be forced down the annulus. It is necessary to insert the hose through an outlet into the annulus region for brine displacement when pressure builds up in the annulus between casing strings due to leaks in the casing. Pressure build-up in the annulus is reduced by pumping a heavy liquid through the hose into the annular space experiencing the pressure build-up. A nozzle is affixed to the lower end of the hose. The hose may be inserted several hundred feet into the well. Therefore, the hose is pressurized to maintain rigidity to keep the hose from winding about the well during deployment. To keep the hose rigid, internal pressure is maintained in the hose. The nozzle is provided with a burst disk that holds the pressure. Once the hose is lowered to a desired depth, an operator may increase the pressure sufficiently in the hose to break the disk, thereby allowing heavy liquid to flow out. The heavy liquid displaces the lighter well product, which flows out of the outlet. An injection sealer at the surface seals around the hose. A gate valve is employed to shear the hose in the event of an emergency.

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First Claim