PSI - Issue 19

Aaron Stenta et al. / Procedia Structural Integrity 19 (2019) 27–40 Author name / Structural Integrity Procedia 00 (2019) 000–000

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2. Life Cycle Management (LCM) The LCM approach for all industrial equipment, and for all damage mechanisms, is outlined by the LCM flow diagram illustrated in Figure 1a. This includes design and construction, determination of operating conditions, inspection planning, performing inspection, damage mechanism identification, determination of necessity for and then performing fitness for service (FFS) analysis to evaluate damage, and utilization of post-inspection maintenance and repair guidelines for the decision to either run, rerate, repair, retire, or replace. As noted in each of the boxes of the diagram, and specifically for the U.S. oil and gas, refining, and petrochemical industries, there are well-defined industry codes, standards, and best practices for many of the components of LCM. However, one critical aspect missing from this LCM flow diagram is cost. At each decision point, a cost is

Fig. 1. (a) Life Cycle Management (LCM) flow diagram; (b) life cycle decision flow diagram.

usually the driver for veering one way or another. An extended LCM decision flow diagram, with costs incorporated throughout, is illustrated in Figure 1b. These costs include installation, inspection, FFS, maintenance, and failure. This high-level flow diagram is applicable to all damage mechanisms throughout all industries. This decision flow diagram compactly illustrates the cycle of decisions that are made and the high level actions that are performed at each stage. Also, the costs and benefits that result from the actions are explicitly indicated. These are the costs that would be added incrementally over the lifetime of the component as each decision point is reached or as each event occurs. The sum of all of these results in the final value of the lifetime return H in Eq. (1). The steps in the flowchart are color coded based upon their function. The orange steps are decision points, where