Published on 14 January 2019
Saltel High Temperature Patch repairs leaking casings
Successful High Temperature patch installations in Californian thermal wells.
Numerous wells in California use thermal recovery techniques to extract oil. According to a report by Yale University, steam has helped make this state the 3rd largest oil producer in the US, after Texas and North Dakota. The age of wells, combined with the corrosive downhole conditions, has made casing leaks a common challenge.
Saltel Industries successfully completed the installation of 3 patches, to repair shallow casing leaks in 2 Cyclic Steam Stimulation (CSS) wells, for an operator in California, USA. The client was looking for a remedial solution displaying strong resistance to maximum 380 degF [193 degC] temperature, during steam injection cycles, and also capable of sealing during production at low temperature.
The Saltel Patch was selected for its easy conformance to irregular geometries and its ability to be set gently against fragile tubulars, while offering strong sealing characteristics. The need to run a second patch in the same well also required patch through patch capabilities, and Saltel Patches could meet the requirement.
1st well – 2 patches
Both patches (8-5/8in, Ultraslim, 19.6 ft [6 m] long) were installed in 8-5/8in casing. Top patch was installed to cover 58-61 ft [17.68 – 18.59 m] leak interval. The bottom patch was installed over 711-714 ft [216.71 – 217.63 m] leak interval. The second patch setting is once again confirmation of the patch through patch capability. A solid pressure test (500 psi for 30 minutes) confirmed the leaks were isolated with success.
2nd well – 1 patch
7in Ultraslim, 19.6 ft [6 m] long) set in 7in casing at 120 degF [49 degC] temperature. The patch was set over 406-408ft [123.75 – 124.36 m] leak interval.