Abstrak :
API 5.L grade. B represent the type become militant the low carbon steel is which is most used for the materials of pipe oil and gas. Generally process the taking on pipe conducted with the shielded metal are welding (SMAW) with the form V-groove. All specified period, result of welding experience of the repair. In this research will be compared to result of welding pipe become militant the API 5 L Grade B before and after repair evaluated from nature of micro structure. From the result will be seen by whether repair result fulfill the standard applying to APL 5 L Grade B or do not fulfill.
Result of research that interesting micro structure examination of dominant phase is ferrite (a Fe) and Pearlite (Fe3c).