Well type
Oil Producer
Reservoir type
Carbonate
Enhanced zonal isolation
And cement assurance via 4 x WAB in open hole
Wab rotational capability
Significantly enhanced primary cementing operation
Positive DST results
Validate commercial viability of reservoir
Gas tight wab
Set in 13 3/8” for V0 protection of liner hanger
Short term delivery
Facilitated by Welltec manufacturing capacity
Location
Asia Pacific
Two 1214 WABs were the first of two production wells (gas & oil) with a further potential of seven wells.
This Welltec® Annular Barrier (WAB) value is derived through ensuring pressure isolation of several potential production zones to be Drill Stem Tested (DST), behind the 9 5/8” casing (80° deviation).
The 9 5/8” casing was run with two 1214 WAB positioned to isolate the zone. The cement was pumped and on bumping the plug, the WABs expanded quickly under surface control.
The cementing challenge was exasperated by the depleted zones within the 12 ¼” section and the high angle long length hole. The WABs enabled liner rotation both during deployment and cementing along with providing centralization and anchoring once expanded.
The 8 ½” hole was drilled and a slotted 5 ½” liner completion installed with an Isolation valve to isolate the lower completion.
The 9 5/8” zones were selectively perforated with Tubing Conveyed Perforating (TCP) guns. The first lower zone produced water and was plugged off shallow with a retrievable bridge plug. Subsequent zones were perforated and tested positively. The zone acid stimulated to improve productivity during the DST tests.
Finally, the upper completion was installed.
Second of two production wells (gas & oil) with a further potential of seven wells in 2018. This WAB solution delivers pressure isolation of three potential production zones behind the 9 5/8” casing (80° deviation). Each zone relatively short in True Vertical Depth (TVD) with a potential oil water contact below.
The 9 5/8” casing was run with four 1214 WAB positioned across the 12 ¼’ open hole to isolate the 3 zones across the reservoir section and an additional 1214WAB set within the 13 3/8” casing for B annulus Sustained Casing Pressure (SCP) protection. On bumping the cement plug, all five WABs expanded.
The cementing challenge was exasperated by the depleted zones across the 12 ¼” section along with the high hole angle. The WABs enabled liner rotation during the casing deployment and during the cementing operation, along with casing centralization and anchoring once expanded
The 8 ½” hole was then drilled and a slotted 5 ½” liner completion installed with an isolation valve to isolate the lower completion.
The 9 5/8” zones were perforated with TCP guns and a DST string run and the zone flow tested.
Finally, the upper completion was installed.
Zonal isolation assurance via WAB provides tangible DST result to confirm reservoir viability.
Welltec
WAB® for Well Construction & Integrity (Welltec® Annular Barrier)
CAPEX effective, enhanced well integrity via metal expandable packers