This paper presents an external corrosion prevention equipment lifecycle management approach that aligns with and supports the transition of equipment from a reactive maintenance approach to a reliability-centered and conditioned-based maintenance approach. The lifecycle assessment is comprised of deterministic (remaining life estimate), probabilistic (probability of failure) and fitness for service approaches. The process output is a prioritized and optimized management plan for a set of equipment critical in the external corrosion threat prevention on mainline piping, facility piping, and aboveground storage tanks. The process outcome also forms the basis of planning the equipment's preventative maintenance, refurbishment, replacement, and Long-Range Forecasting (LRF) for funding cycles. Once implemented, the process results in an optimized lifecycle management for equipment which translates into cost savings related to unplanned outages caused by equipment failures and unnecessary replacements. This paper discusses the process as applied to Impressed Current Cathodic Protection (ICCP) anode bed residual life estimates.
Managing the equipment used to prevent external corrosion of buried structures is a critical component of effective corrosion control. Many repairs or replacements are reactive in nature, occurring after a failure. This can result in lack of cathodic protection, or anode beds being replaced prematurely at significant costs to the operator.
A multi-year External Corrosion Prevention (ECP) Equipment Lifecycle management strategy that advances the current maintenance program to a proactive, engineered, reliability-based approach will allow for asset lifespan maximization and minimization of long-term costs, while ensuring the safe operation of the pipeline system. Initial focus has been to understand the asset base, and advance lifecycle management practices for a prioritized asset type. As the strategy progresses, refined modelling and input will enable a reliability-based, predictive maintenance approach to be developed. Figure 1 below depicts the major steps of this strategy.
The external corrosion equipment lifecycle management plan is a step-by-step process of activities conducted at all phases of the equipment life cycle to ensure its reliability and availability. The process described in this paper will be specific to ICCP anode bed life and replacement planning. The application of a similar methodology for Alternating Current (AC) mitigation and other systems has not been developed at this time and will be the subject of a future program.
