Shiro Takada - Emeritus Professor of Kobe University, Japan, Adjunct Professor of University of Tehran, Iran

Re-assessment of existing facilities may involve different techniques and acceptance criteria than used for a new design, depending on the intent of the evaluation, the regulator requirements, and the wishes of the owner. Several key considerations are as follows: (a) Evaluation acceptance criteria (stress and/or deformation limits). (b) Additional requirements related to equipment functionality. (c) Loads on an existing structure. (d) Any changes in the operating basis (weight, operating conditions, etc. (f) Remaining design life. (g) Information from available field observations, such as deterioration. In summary, the best estimate of the structure and material properties should be used to get the most accurate prediction of the structure’s or system’s performance. In maintenance, repair, replace, upgrading and retrofit for oil facilities, two levels of performance: (a) Damage limitation state and (b) Ultimate limit state. In damage limitation state, designed oil facilities shall not have any unacceptable damage to operate oil systems and in Ultimate limit states, designed oil facilities could be allowed to have minor physical damage without giving the effects of human lives and environments and without loosing stability of oil refinery and supply systems. The restoration from the damage states shall be back soon. Below figure shows the performance level taking consideration of deterioration and seismic forces.The target components of the oil refinery in this paper are (1) Piping and pipeline, (2) Horizontal vessel, (3) Tower and vertical vessel, (4) Spherical tank and (5) Foundation. Damage of existing facilities, Data gathering for retrofit, Inspection and evaluation and Retrofit procedure are discussed for above facilities taking consideration of RBI(risk based inspection).