Shifting 11 sleeves in one run to reduce water cut

Challenge
Water shut-off
JRU181202 Shifting 11 sleeves in one run to reduce water cut - Well Intervention - Welltec
  • Max. depth 4,800 m (15,748 ft)
  • Max. temperature 73°C (163°F)
  • Pressure 133 bar (1,929 psi)
  • Distance tractored 5,232 m (17,493 ft)
  • Sleeves shifted 11 in 1 run
  • Water cut Decreased from 70% to 30%.

Background

A client offshore Russia contacted Welltec® about closing well intervals to mitigate a water cut issue. The client was experiencing nearly 70% water cut in a 15,748 ft 90° well. The 5.5″ completion was designed with flow control devices to control well production from each zone. To reduce the water cut, the client decided to close the bottom 11 flow control sleeves to shut off the production in these zones.

Initially, a third-party service provider attempted to shift the sleeves closed six months earlier. That attempt, however, failed when a restriction in the well circulation valve prevented the provider from reaching the shifting intervals at 3,160 meters.

Operation

Welltec proposed using a combination of the Well Tractor®, Well Stroker®, Well Key®, and a multi-finger caliper tool to close the control device sleeves. This method was chosen because the caliper tool could intelligently confirm the shifts in the sleeves during the same run. After performing an SIT to prove the concept, Welltec mobilized to the platform.

On site, Welltec was in charge of all operations. The Well Tractor 318, Well Stroker 314, Well Key 325, and a multi-finger caliper tool were run in hole. In one run lasting only four hours, Welltec closed the 11 flow control sleeves successfully. During this same run, Welltec also confirmed by caliper that the sleeves had shifted. In a second run, production logging confirmed that all 11 flow control valves were closed with no flow from the screens.

Achievements

This operation represented the first shifting job in this field. Welltec mobilized to the site quickly and met the client’s objectives in a single run without hanging up at the circulation valve restriction. Welltec’s procedure of including the multi-finger caliper tool below the Well Key helped to confirm that the sleeves had been shifted closed.

Since closing the 11 control device sleeves, water cut in the well has decreased from nearly 70% to 30%. Welltec’s work decreased the time for the client to achieve crude oil. In addition to the time savings, reducing the water cut has also saved the client significant costs.

Welltec has long been known for conveyance operations in Russia, but that may be changing in light of this mechanical shifting success. The client was very satisfied with Welltec’s results on this operation and has requested the same work on another well in the near future.