The Radial Bond Log Tool (RBT)

The Radial Bond log Tool (RBT) provides proven superior reliability and responsiveness even in thin cement sheath conditions. With circumferential cement bond evaluation, the RBL identifies channels, in addition to standard cement bond logging. The main application of the Radial Bond Log Tool is to evaluate hydraulic isolation between producing and non-producing zones– a key factor needed to assess the integrity of the well.

The RBT features a powerful sonic transmitter and an array of radially segmented acoustic sensors that derive a calibrated amplitude measurement of the induced sonic signals as they propagate along the length of the casing or liner. These segmented measurements enable the identification of small axial channels. In addition, the tool provides the traditional 3 / amplitude and 5 ft. VDL measurements to provide comprehensive evaluation of cement to casing and cement to formation bonding.

Temperature Range -25?175ºC
Pressure Rating 20000Psi
Vibration Rating 5g(5?150Hz,3D)
Working Voltage 100 VDC
Current 180±10%mA
Receiver Spacing 1.5ft(457.2mm),3ft(914.4mm),5ft(1524mm)
Sonic resolution 6 points/ft(when speed at 550m/h)
Sonic accuracy ±5%
Suitable casing 4.5??9.5?
Resonance frequency of T/R transducer 15.5 KHz ?20.5 KHz
Max Logging speed 550 m/h
OD of the tool 2 ¾ in
Effective length of the tool 3.8 m
Weight 200 lbs


Temperature sensor TEMP acquires real-time well temperature, whenever mud density is in two extreme conditions: if mud density is too high to close acoustic impedance of cement or too small (0.1-1.0) leading to huge difference regarding acoustic impedance, the CBL curve will result in wrong cementing. However, temperature parameter solves it well, normally the client asks for CBL logging within 24-48 hours since cementing is done, because cement will release heat during the course of freezing, well temperature increases as well, so the provided real-time well temperature will help us to evaluate cementing accurately Transmitting transducer XMIT concludes two full-electrode transducers which been radial polarized.


  • Full circumferential resolution for better channel identification.
  • Provides a 360-degree cement map.
  • Cement bond quality measurement in slim and conventional wells.
  • Indicates channels and intervals using radial receivers.
  • Measures the attenuation of the acoustic in the casing to cement interface.
  • Cement bond evaluation behind casing.
  • Cement top identification.
  • Cement to formation bond evaluation.
  • Micro-annulus detection.
  • Cement bond evaluation prior to Well Abandonment.
  • Single transmitter with 3 (near) and 5 (far) receivers.
  • 8-segmented radial receiver array for radial cement imaging.
  • Slotted sleeve design for improved rigidity, strength, and acoustic isolation.
  • Horizontal/deviated hole investigations (for example, combined with the UW inclinometer tool to determine high-side)

RBT Log Sample