Operators in Canada frequently use steam-assisted gravity drainage (SAGD) as an enhanced oil recovery technique. The SAGD technique uses steam pumped down an injection well to heat up the surrounding formation and hydrocarbons to lower viscosity. This process enables the heavy oil to then be pumped to surface from a neighboring producing well.

A client in Canada experienced issues with steam conformance. The distribution of steam was not even throughout the lateral section of the well. An initial consideration included pulling the injection tubing in order to move steam ports, but this method cannot be modeled effectively. Additionally, the client would experience multiple days of downtime with uncertainty regarding the success of pulling the lower completion in an older well.

The client preferred a precise solution and a known flow area without having to pull the lower completion. During a conversation concerning production optimization, Welltec® offered a solution using the Welltec Puncher® 218, to add steam flow channels.

Welltec mobilized to the well site with the Welltec Puncher and Well Tractor®, as well as an assortment of other tools. All equipment was tested individually and on wireline. After completing initial tests, the tools were run in hole. The static well temperature was 392˚F (200˚C), so cool fluid was pumped from the surface while the Welltec Pressure Temperature Tool (WPT) measured well temperature in real-time and relayed data back to the surface. Throughout the operation, the real-time readings from the WPT enabled surface personnel to adjust pump rates to maintain ideal temperature parameters for the tools.

Upon reaching the point of refusal, Welltec performed a casing collar locator (CCL) log to correlate the depth. The Well Tractor was then used to convey the tools to a depth of 5,545 ft (1,690 m), past the deepest punch depth. A CCL logged back up to 3,740 ft (1,140 m), the entire interval to be punched. The toolstring was then tractored back down to position it for the punching operation.

The Welltec Puncher performed 18 punches between 5,545 ft (1,690 m) and 3,740 ft (1,140 m). The Well Tractor conveyed the tool string a total of 4,265 ft (1,300 m). After performing the punches, the toolstring was pulled out of hole. Despite this operation serving as a trial scenario in a lateral well and high-temperature environment, the client was pleased with the operation’s results

The primary result and benefit of Welltec’s solution is that the client now has a known hole size to be supplied for steam injection in order to quantify the amount of outflow when injection restarts. The client can now work smarter by optimizing injection.

Furthermore, running this job on wireline was faster than the alternative methods. The job took 12 hours, slightly faster than tripping in a pipe-conveyed system and 12 hours faster than a rig pulling the completion. There is also the always-present risk of problems occurring when trying to pull the lower completion in older wells. The client saved on costs and nonproductive time. Finally, HSE risks were mitigated as the job was performed with limited overhead lifting.