Underwater pipeline inspection crawler

A method for traversing a weld joint along a surface of an underwater pipeline with an inspection crawler having a housing, a power source, a controller, at least one inspection tool, at least two pairs of latching arms including a front pair and a rear pair, each latching arm having a rolling element, and at least two pairs of driving wheels, the method comprising:

• parking the inspection crawler at a location proximate to the weld joint, wherein the step of parking comprises pressing the rolling elements of the at least two pairs of latching arms against the surface of the pipeline such that the rolling elements of the front pair of latching arms are substantially aligned with the rolling elements of the rear pair of latching arms;
• lifting the rolling elements of the front pair of latching arms from the surface of the pipeline;
• propelling, using the driving wheels, a front portion of the inspection crawler across the weld joint;
• lowering the rolling elements of the front pair of latching arms to contact the surface of the pipeline and lifting the rolling elements of the rear pair of latching arms from the surface of the pipeline;
• propelling, using the driving wheels, a back portion of the inspection crawler across the weld joint;
• and
• lowering the rolling elements of the rear pair of latching arms to contact the surface of the pipeline.