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Case Study: Oil Production Exceeds Estimates After Perforating 1,150 ft in a Live Well with 1,800-psi Underbalance

PowerJet Nova shaped charges and CIRP technology maximize productivity and minimize perforation damage

Challenge: Maximize productivity from 1,150 ft [350 m] of perforations by increasing penetration and eliminating perforating debris and production-impairing kill fluids.

Solution: Use PowerJet Nova extradeep penetrating shaped charges and CIRP completion insertion and removal under pressure equipment to perforate the long interval underbalanced without killing the well.

Result: Improved well performance and executed the complex operation in a single trip without any equipment failure or safety incident.

Underbalance perforation required over extended interval in live well

An operator required perforating 1,150 ft of pay zone in an offshore well in the South Pacific with completion already installed. The perforation interval was 14,933 ft to 16,081 ft [4,551.5 m to 4,901.5 m] with a reservoir pressure of 7,400 psi and temperature of 248 degF [120 degC]. The operation had to be performed with an underbalance of 1,800 psi and without killing the well. This process would remove perforation debris, providing a clean path from the reservoir to the wellbore, and protect the perforation tunnels from potential damage from production-impairing kill fluids.

CIRP equipment and CT enabled complete operation in a single trip

SPAN Rock stressed-rock perforating analysis, which estimates charge penetration using a model based on tests conducted under downhole conditions, indicated that PowerJet Nova extra deep penetrating shaped charges would be the most effective solution. These charges improve the efficiency of explosive energy transfer into the perforating jet using an optimized design that dramatically increases penetration and, hence, drainage contact area and productivity. The charges were deployed with 49 × 20 ft of 27⁄8-in HSD high shot density gun systems conveyed on 1.5-in coiled tubing (CT). The guns were made up with CIRP connectors, which allow long gun strings to be used under pressure with shorter lengths of lubricator. They were deployed using sealed ballistic explosive transfers and a CIRP deployment stack.

After depth correlation, circulation was established through the CT, and a four-pulse pressure signal was sent downhole to activate the firing head. No high surface pressure or flow rate at the firing head was required, reducing risk and firing-sequence complexity. After the guns were fired, the CT was pulled out of the well, and circulation was established to keep the gas cap down and avoid high surface pressure. The guns were reverse-deployed under pressure.

Deep, clean perforation tunnels improved production beyond estimates

The entire operation—involving careful planning and clear communication and cooperation among several teams—was conducted smoothly with no equipment failures or safety incidents. The single trip minimized operating time and risk, improving well performance beyond expectations.


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