uHPHT Single-Shot Reservoir Testing Systems

Simple, rugged, reliable test strings for ultraHPHT wells

Successfully test in the most extreme environments

Schlumberger uHPHT single-shot test strings operate in hostile downhole conditions with a special seal package developed and tested for ultrahigh pressures and temperatures.These strings reliably perform with a simple, rugged design that can handle the most extreme testing environments.

The two string configurations can dependably perform in

downhole temperatures to 500 degF
differential pressures to 17,500 psi
annular pressures to 25,000 psi with the J-string
annular pressures to 30,000 psi with the K-string.

The industry defines 300 degF, 10,000 psi, and above as HPHT, and there exist several higher plateaus defined by metallurgical, elastomeric, chemical, and electronic limits. Wells of 500 degF, 30,000 psi, and beyond exist, and Schlumberger has the equipment and personnel that can service them.

J-string: 25,000-psi annular pressure applications

The HPHT-rated J-string configuration is designed to accommodate downhole temperatures to 500 degF, differential pressures to 17,500 psi, and annular pressures to 25,000 psi. The rugged yet simple design is based on single-shot tools.

The J-string has undergone qualification testing that combined maximum pressure of 25,000 psi with maximum temperature of 500 degF. The J-string uses our proprietary sealing technology, tested and proved in fields with extreme conditions worldwide.

K-string: 30,000-psi annular pressure applications

The HPHT-rated K-string configuration is designed to accommodate downhole temperatures to 500 degF, differential pressures to 17,500 psi, and annular pressures to 30,000 psi. The rugged yet simple design is based on single-shot tools.

The single-shot K-string can be run with a dual-action valve (DAV) in the string, providing a second buildup option for more flexibility in test design while ensuring the same reliable single-shot principle. When run with the DAV-K tool, the K-string is rated to 450 degF.