Schlumberger Introduces New Service to Evaluate Zonal Isolation

Schlumberger introduced its new Isolation Scanner cement evaluation service. This unique service enables accurate evaluation of traditional, heavyweight and latest generation lightweight and foam cements.

By measuring radially and deeper toward the formation, the Isolation Scanner confirms zonal isolation, pinpoints any channels in the cement and ensures confident squeeze or no-squeeze decisions. In addition, due to its depth of investigation, the Isolation Scanner provides detailed information about casing and casing-within-casing eccentralization, while ID and thickness measurements identify any corrosion or drilling-induced wear.

"The Isolation Scanner uses new technology that permits the evaluation of the latest generation of light-, ultra-light- and heavyweight, as well as conventional, cements," said Sami Iskander, president, Wireline, Schlumberger. "We can now confidently differentiate low-density solids from liquids, so customers can distinguish lightweight or foam cements from contaminated cement or liquids."

With more than 80 jobs conducted in the North Sea, Europe, Africa, Middle East, North America and the Gulf of Mexico, the Isolation Scanner has proved its effectiveness in evaluating a wide range of cement weights. This service provides customers with insight into the quality of their cement job design that was not previously possible.

The Isolation Scanner combines traditional pulse-echo techniques with a new ultrasonic technique that induces a flexural wave in the casing using a transmitter and two receivers. The analysis of the flexural waves at the two receivers enables the characterization of the cased-hole environment in terms of the acoustic velocity of the material filling the annulus between casing and formation or the second casing string. Additionally, it provides the position of the casing within the borehole or a second casing string, and the geometrical shape of the wellbore.