Successful Patch through Patch operation to cover off-depth perforations
After a previous split casing repair with Saltel Patch, a second one was successfully installed to isolate off-depth perforations.
Large Drift ID clearance allows Patch through Patch operation, to cover off-depth perforations. A first casing patch (17.5m 5.5in reinforced) was set last November 2017 at 3,000ft across a casing split. The stainless steel expandable inner-lining was combined with a cement squeeze to increase its mechanical resistance to frac pressures). Amongst the many original qualities of this expandable steel patch is the large ID, making it possible to run perforating guns, plugs, or other tools through the set Patch. During the wellbore preparation before a frac, the perforating gun fired off depth below the first patch.
In January 2018 a second casing patch (The 150th in the US since the beginning, 6m 5.5in slimline) was run through the first Patch (patch thru patch), and set to seal off the unwanted perforations. The well was then fractured in 52 stages, at 5,670psi. The client pumped an average of 365,000lbs of sand in each stage. This job illustrates the capacity of the expandable inner-lining seal effectively with high pressures, repeated pressure cycles, high flow rates, and large volumes of fluid and sand (Total 8,627 tons), while still leaving access to the well below.