4 1/2-in. Radial Bond Tool


Provides improved evaluation of azimuthal cement bond in large casings that sector bond tools of conventional sizes cannot access


  • Cement evaluation in large casing
  • Combining with compensated neutron, gamma ray, gamma ray neutron, and casing collar

Features and Benefits

  • A 22.5° azimuthal resolution on cement maps provides details necessary for identification of channeling, voids, and other bonding irregularities for more comprehensive and accurate logs.
  • Temperature sensors enable real-time tool-quality controls for greater operational efficiency while saving rig time and associated costs.
  • Two receivers—each containing 16 directional receivers—combine to provide and confirm cement evaluation data, enabling the operator to make crucial well decisions.
  • Rigid V-slot isolator bars in the tool body minimize flexing of the tool body for optimum centralization in deviated wells.
  • Wave-display spacing on the variable density log (VDL) produces a higherquality, more accurate log for large boreholes.

Tool Description

The 4 1/2-in. radial bond tool* addresses the challenges of cement-integrity evaluation in large wellbores. The tool is larger in diameter and more rigid than standard-sized tools, and its receivers are spaced to provide a deeper measurement investigation.

Typically, casing larger than 9-5/8 in. is challenging for cement evaluation with conventional-sized tools (diameters of ≤3 3/8 in.) because of the difficulty of properly centralizing the tools and the additional signal attenuation from the borehole fluid. The relatively flexible nature of the tool housing adds to this challenge. Attempting these measurements in large casings with standard tools results in increased uncertainty of cement quality and the hydraulic isolation it provides. Large casings are typically used near the surface and provide critical well-integrity protection.

The 4 1/2-in. radial bond tool measures acoustic signal amplitude and attenuation using two receivers—one 3 ft (0.9 m) from the sonic transmitter and a deeper one at 6 ft (1.8 m). Each receiver contains 16 directional receivers (with 22.5° azimuthal sector resolution) to produce a cement map to identify voids, channels, and other potential issues with the cement quality.

*The 4 1/2-in. Radial Bond Tool is a product of Hunting Titan, Ltd.