TANK DIMENSION (PLUMBNESS & ROUNDNESS)
Method of Inspection
Plumbness Field measurements were carried out using Total Survey Sokkia 650RX. Readings were taken at 8 locations (at equal spacing) of shell circumference from tank external. Two point readings were taken on each shell course.
Roundness The measurement of the tank radius was taken at the bottom course of the tank shell at 8 stations with equal interval. It is also taken at 1 foot height from the shell to bottom weld toe.
Plumbness As per API 653, Clause 10.5.2, the maximum out-of-plumbness on the top of the shell relative to the bottom of the shell should not exceed 1/100 of the total tank height with a maximum of 5 inch (127mm). For Tank Tank-F, with tank height is 16250 mm, Acceptance Limit: 1/100 of the total tank height with a maximum of 5 inch (127mm) : 127 mm