Patent ID: 8291780
Filing Date: 2012-10-23
Classification: G01N

Abstract:
1. An in-line pipe inspection tool having at least one inspection sensor module, the sensor module comprising: a support mounting the module on the tool; a finger pivotally connected to the support; at least one inspection sensor at the end of the finger remote from the support; resilient biasing means for resiliently biasing the finger such as to move the at least one inspection sensor away from the support; and at least two biasing sensors for detecting movement of the resilient biasing means corresponding to movement of the at least one inspection sensor towards or away from the support and compensating for a thermal drift of said resilient biasing means, wherein the resilient biasing means comprises a first leaf spring and a second leaf spring, and wherein at least one of said at least two biasing sensors is configured at a location on a lower portion of a leading edge of said first leaf spring and at least one of said at least two biasing sensors is configured at a location on a lower portion of a trailing edge of said first leaf spring with said leading edge and said trailing edge respective to an operational direction of movement of said pipe inspection tool, wherein said locations of said at least two biasing sensors are adjacent; and further wherein the at least one inspection sensor and at least two biasing sensors simultaneously monitor the magnetic and distortion characteristics of a pipe.