Improving Steam Injection in California November 2019
Well Intervention with Wel-lok™ Perf-lok
1: Issues to overcome
Temperature in these wells during steam injection can reach as high as 330°F (165°C) and the operator wanted full bore access in the casing after the hole was plugged. Although steam could be injected into the zone, injecting a viscous fluid like cement or resin was difficult and due to the downhole temperature often unreliable.
Utilizing a wireline unit, a Wel-lok™ Perf-lok was set inside the 3 ½” casing across the ¼” perforation hole. The bismuth alloy was melted, flowed into the perforation hole via gravity (no injection required) and expanded after solidifying to plug the hole. The remaining bismuth alloy plug inside the 3 ½” casing was milled out leaving only an alloy plug in the perforation hole and full bore access inside the casing.
After successfully setting and milling out the alloy plug, an injection survey was performed. This survey showed the “thief” hole had been plugged and all the steam was being injected into perforations deeper in the well, just as the client had requested.