They're designed for use in tight tolerance casings where the centralizer is required to compress fully to travel between tight casing strings, yet expand to designed open hole size.
The new tools are engineered to precise ring-gauge tolerances, partly because casing drift downhole is a major concern when running deep water wells. Also, the centralizer must compress as closely as possible to the casing as every millimeter saved allows for greater expansion in the open hole, declares the manufacturer.
UROS-CT fits straight onto standard casing joints. There is no need to run an expensive pup joint and substantial rig make-up time is said to be avoided. They deliver high levels of standoff for better well clean-out during conditioning. Models are being used at various water depths from 5,000 ft.