Abstract: An inspection sensor module for an in-line pipe inspection tool has a support for mounting the module on the tool, a finger pivotally attached at one end to the support and pivotally attached at the other end to a sensor block carrying one or more inspection sensors. A first leaf spring extends from the support to the finger to bias the finger outwardly, and a second leaf spring extends from the support to the carrier to bias the sensor block. Biasing sensors are mounted on the leading and trailing edges of the first leaf spring to detect movement of the first leaf spring corresponding to movement of the inspection sensors towards or away from the support.

Abstract: An inspection sensor module for an in-line pipe inspection tool has a support for mounting the module on the tool, a finger pivotally attached at one end to the support and pivotally attached at the other end to a sensor block carrying one or more inspection sensors. A first leaf spring extends from the support to the finger to bias the finger outwardly, and a second leaf spring extends from the support to the carrier to bias the sensor block. Biasing sensors are mounted on the leading and trailing edges of the first leaf spring to detect movement of the first leaf spring corresponding to movement of the inspection sensors towards or away from the support.

Abstract: A pipeline inspection and defect mapping system includes a pig having an inertial measurement unit and a pipeline inspection unit for recording pig location and defect detection events, each record time-stamped by a highly precise onboard clock. The system also includes several magloggers at precisely known locations along the pipeline, each containing a fluxgate magnetometer for detecting the passage of the pig along the pipeline and further containing a highly precise clock synchronized with the clock in the pig. The locations of the various magloggers are known in a north/east/down coordinate system through a differential global positioning satellite process. Finally, a postprocessing off-line computer system receives downloaded maglogger, inertial measurement, and odometer data and through the use of several Kalman filters, derives the location of the detected defects in the north/east/down coordinate frame. Consequently, a task of identifying sites for repair activity is much simplified.