miner76
Petroleum
- Aug 10, 2006
- 1
Corrosion logging indicates that I have a gas storage well that appears to have a crack in the casing at a shallow depth (less than 200' from surface). A caliper log shows a restriction at the same depth. A downhole camera was run and while the picture isn't crystal clear, it also shows a defect. The casing is cemented in and there is another string of casing behind the production casing. I am not seeing any evidence of pressure behind the casing at the surface, and neutron logs do not indicate that I have gas migrating to any upper zones. The well has a tubing string, but it is just in place to be used as a kill string, and all injection & withdrawal uses the annulus.
I am looking at options for repair. It appears that there is sufficient cement bond to make backing off the casing REALLY difficult, and cutting the casing and trying to pull the casing would also be difficult, so replacing the bad joint or using an external casing patch don't seem like attractive options. Because of this I'm considering the following options: 1) run an internal casing patch 2) cement in a new liner 3) setting a packer near bottom, pickling between the liner and the casing with corrosion inhibitor and producing up the tubing. Both option 2 & 3 will reduce the gas volume that can be injected or withdrawn, so I like the idea of the patch. Has anyone had experiences with internal casing patches? The HOMCO patch that Weatherford markets is the one I have been looking at.
I am looking at options for repair. It appears that there is sufficient cement bond to make backing off the casing REALLY difficult, and cutting the casing and trying to pull the casing would also be difficult, so replacing the bad joint or using an external casing patch don't seem like attractive options. Because of this I'm considering the following options: 1) run an internal casing patch 2) cement in a new liner 3) setting a packer near bottom, pickling between the liner and the casing with corrosion inhibitor and producing up the tubing. Both option 2 & 3 will reduce the gas volume that can be injected or withdrawn, so I like the idea of the patch. Has anyone had experiences with internal casing patches? The HOMCO patch that Weatherford markets is the one I have been looking at.