Modular Borehole Caliper Toolstring for Localized Casing Corrosion

The toolstring is divided into modular components including multiple caliper modules with radially rotatable fingers, a power and control module, and a data processing system. Each module performs specific functions independently, allowing high-precision measurement through coordinated operation of segmented components while maintaining manageable system complexity through modular design.

The system transitions from conventional single-point or limited-point measurements to three-dimensional borehole imaging by capturing internal diameter data across multiple azimuths and depths. The radially rotatable fingers collect measurements at different angular positions, creating a comprehensive 3D representation of casing conditions that enables detection of small localized faults invisible to conventional methods.

The system performs preliminary alignment and merging of multiple borehole image logs during the data acquisition phase. The power and control module coordinates the radially rotatable fingers to collect data in a systematic sequence that pre-establishes spatial relationships, enabling faster processing later. Depth alignment and azimuthal registration are initiated during logging operations rather than as separate post-processing steps.

The system creates multiple copies of borehole image logs from different measurement passes or tool strings, then merges these copies to enhance resolution. By acquiring redundant data sets and combining them through alignment algorithms, the system achieves higher measurement precision while distributing the processing workload, reducing the time penalty associated with high-resolution imaging.