Cement Bond Log

What Is a Cement Bond Log?

A Cement Bond Log (CBL) is an acoustic measurement used to evaluate the quality of the bond between the casing and the cement placed in the annulus. This critical evaluation helps operators confirm that cement is properly isolating zones downhole, preventing unwanted fluid migration between formations.

At Thermal Tech, we use industry-standard sonic logging tools to deliver reliable, high-resolution cement evaluation data that supports informed decision-making for completions, workovers, and regulatory compliance.

How It Works

Our cement bond logging tools transmit an acoustic signal through the casing and measure the amplitude and travel time of the returning signal. A well-bonded casing will show a rapid signal attenuation, while a poorly bonded or free-pipe section will show high-amplitude returns.

• Amplitude Measurement – Evaluates the strength of the cement bond by measuring signal attenuation across the casing wall.
• Variable Density Log (VDL) – Provides a full-waveform display that reveals both casing-to-cement and cement-to-formation bond quality.
• Transit Time Analysis – Confirms casing condition and identifies areas of potential channeling or voids in the cement sheath.

Applications

• Zonal Isolation Verification – Confirm that cement is effectively isolating producing zones from water-bearing or gas-bearing formations.
• Pre-Workover Assessment – Evaluate cement integrity before perforating, stimulating, or squeezing to reduce risk and optimize operations.
• Regulatory Compliance – Meet state and federal requirements for well integrity documentation and reporting.
• Plug & Abandonment Support – Verify cement placement during well decommissioning to ensure long-term environmental protection.