Well type
Produced water re-injector
Max. deviation
65.6˚
Max. operating depth
11565 ft (3525 m)
Total depth
15627 ft (4763 m)
Temp. at operating depth
149˚F (65˚C)
A client offshore Norway needed to remove a stuck high expandable bridge plug and fish. Prior efforts with a mechanical bailer had failed to remove the plug. The client was uncertain about the nature of the stuck plug, with possibilities including the fish stuck mechanically to the plug, stuck differentially because of a leak through the plug, or stuck because of debris above the plug. Additionally, there was extremely limited rig-up height available, and the fishing string needed to be able to latch to the fish and slide over the overshot above with a 0.59” edge into the 7” tubing.
The client has worked with Welltec® in the past with several good experiences, including the Well Cleaner Power Suction Tool (PST). The client contacted Welltec for a solution. Welltec developed a modified solution using the Wellgrab™ Electric Fishing Release Tool (EFRT) that could simultaneously enter the edge and latch on the fish with the Well Stroker® with the ability to anchor up in the 7" tubing as well as the overshot with an ID of 7.35".
The first objective was to pull the fish loose and release it with the Wellgrab. The Wellgrab was run in hole with the Well Tractor® and Well Stroker. On the first attempt, the Wellgrab latched the fish. The fish string came loose after eight strokes. The movement on the stroker indicated that plug was stuck in heavy debris. Due to limited rig-up space, the fish could not just be pulled out of hole. Instead, the Well Stroker pulled up 10 m, and the Wellgrab released the grip on the fish. Next, the Wellgrab was run in hole using a shorter tool string to optimize the length of the bottom-hole assembly and make enough space to take the fish out to surface. It successfully latched the fish and pulled it out of hole.
Over the next several runs, Welltec used the Well Tractor, Well Stroker, and Well Cleaner PST High Vacuum to clean out debris around the plug, retrieving 208 L of baracarb. On the 13th run, deposits and hard debris on the plug fish neck prevented pulling the plug. For the next two runs, the Well Cleaner Reverse Circulating Bit was used first with a mud paddle bit and then the wire brush to clean out settled debris on top of the plug and fish neck, retrieving 14 L of mixed debris.
Finally, the Wellgrab EFRT and Well Stroker with 5200 lbs of force pulled the plug successfully.
The client was both impressed and happy with the flawless execution of this operation and the effort put into the detailed planning and fast turn-around time. Welltec managed to execute the complex operation efficiently, addressing multiple challenges, in limited time.
Wireline proved to be lightweight, less risky, and more cost effective, as competing solutions would have required more rig space and resulted in significant costs in time and money.