Accelerated atmospheric corrosion behavior of carbon steel pipes subjected to cyclic salt spray test was performed according to ISO 14993 – Corrosion of metals and alloys – Accelerated testing involving cyclic exposure to salt mist, “dry” and “wet” conditions [1]. In order to investigate the effect of degree of exposure to environment of inner surface of the pipe on corrosion behavior of inner surface of the specimens, degree of completeness of weldment, 0%, 50%, 80%, and 100%, of steel cover plate is varied. Exposure times in this study are 168, 336, and 504 hours which can be correlated to 10, 20, and 30 years exposed to C3 corrosivity category according to the definition of ISO 9223 – Corrosion of metals and alloys – Corrosivity of atmospheres – Classification, determination and estimation [2,3]. After testing, visual inspection on outer and inner surfaces of the specimens were performed. In addition, average corrosion rate of the specimens were performed according to ISO 8407 – Corrosion of metals and alloys – Removal of corrosion products from corrosion test specimens [4]. The results show that as-received steel pipe specimens exhibited great degree of corrosion attack on the inner surface of the specimens while slight amount of corrosion was observed from the welded pipe specimens.