WELL STROKER® RESTORES WELLBORE ACCESS IN EAST AFRICA

Background

During well intervention operations in a vertical gas well in East Africa, an operator set a lower isolation plug in the 5” tubing. After successful inflow testing, the operator proceeded to set an upper isolation plug in the tubing retrievable subsurface safety valve (TRSSSV) profile to provide a double barrier during well integrity repairs to the christmas tree. The upper isolation plug failed during inflow testing; it was blown up the hole and became wedged at the tubing hanger area.

The operator made several attempts to fish the 3.812” plug from the hanger with braided fishing line, but the shallow depth made it impractical to apply any significant pulling force. The operator investigated using conventional solutions. Coiled tubing was not cost effective. “Hand jarring” with slickline was not successful.

Ultimately, the client chose Welltec’s Well Stroker® XXS to free the plug. Furthermore, the Well Miller® was chosen as a secondary option to pulling the plug. A successful SIT performed before the operation showed that the Well Miller® could mill and remove both the prong and plug body from inside a test pipe. Welltec’s tools were considered safer and faster than conventional solutions because of e-line’s simpler rig up and execution.

OPERATION

On the first run, the Well Stroker® latched onto the prong and pulled it free with over 50,000 lbs of upward force as indicated on the surface panel. During the second run, the Well Stroker® initially latched onto the plug body and stroked up multiple times without moving it. A decision, therefore, was made to stroke down. The plug finally moved downward after 23,000 lbs of force. After multiple downhole strokes, the Well Stroker® pushed the plug below the wellhead where it fell back to the TRSSSV profile.

After the Well Stroker® successfully freed the plug and pushed it back to the TRSSSV profile, conventional slickline latched onto the plug and pulled it out of the hole

ACHIEVEMENTS

Welltec’s e-line fishing solution provided the client with access to the well so the scheduled slickline interventions could continue. The whole operation—the runs with the Well Stroker® and slickline—took two days to successfully retrieve the prong and plug whereas the alternative solutions were unsuccessful after months of multiple attempts. The Well Stroker’s ability to anchor and provide maximum pull directly at the plug was key to the success of this operation.

The client saw great value in using Welltec’s solutions and now is working to set up a direct contract for future interventions after the success of this e-line fishing solution.

TYPE OF WELL: VERTICLE GAS PRODUCER

 

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