Conducting a materials failure analysis requires a carefully planned series of steps intended to
arrive at the cause of the problem. Consistent with the current trend towards better accountability
and responsibility, failure analysis purpose has been extended in deciding which party may be
liable for losses, be they loss of production, property damage, injury, or fatality [1]. Hence it
increases the importance of proper implementation of characterization tools in failure analysis to
rightly identify the failure mode.
Present work discusses a few case studies to shed light upon the importance of the metallurgical
characterization tools and techniques in identification of correct failure mode. Some typical case
studies where metallography plays a very important role have been discussed, such as improper
welding joints which led to premature failure, sensitization and stress corrosion cracking in S.S.,
improper heat treatment and forging indicated the microstructures which led to the premature
failure. These cases are examples of only a few laboratory based investigations which justify that
without metallography it is not possible to diagnose the causes of premature failures.
Generally, examination of failed components commence with the low-power stereomicroscope
whereas hand-held magnifying lenses are still in wide use by experts to study fractures mostly
limited now for field purpose [2]. Metallographic examination typically is performed after nondestructive
and macroscopic examination procedures while using the light optical microscopy
which helps to assess the failure mode with respect to material defects, shortcomings in
processing, metallurgical changes etc. Since light optical microscopy has limited value for direct
observation of fracture surfaces (more limited for metals than non-metals), with still more factual
information can be gathered by scanning electron microscopy at higher magnification.

The integrity of new pipeline projects is critical to Saudi Aramco to avoid any short or long-term impact on the supply of energy. During construction activities, pipeline internal welding inspection is carried out in compliance with international and Saudi Aramco requirements. The visual inspection of internally cladded girth welded pipes requires extra care to avoid any improper field fabrication errors during welding, especially at the root pass area. Such errors can limit the inspection capability and compromise the integrity of pipeline network with possible degradation of corrosion resistance at/near the weld rot, resulting in premature failures. Currently, projects utilize conventional tools such as borescope which is time consuming with limited inspection capabilities (up to 150 meters inside the pipe) and system maneuverability at inspection locations.
The Saudi Aramco Inspection Department enhanced their active inspection technology program and collaborated with a local technology developer. They trialed a wireless crawler robot, which is a high resolution remotely operated robot capable of inspecting internal girth welds with 5000 meters travel capability inside the pipes. The robot can inspect internal girth welds in the field, and inside pipelines with internal diameters of 6 inches and above, and wirelessly transmits the visual inspection results to the outside control room for a timely assessment and critical decision making. The internal visual inspection with wireless crawler robot will help in improving the project progress, reducing repair costs, by identifying defective welds before coating application.