- Companies are increasingly operating assets beyond their original design lives instead of building a new plant and investing in new assets.
- Three main elements of an integrity management review involve the reliability and integrity of the assets; the effectiveness of the systems and procedures that are in place to control operation and maintenance; and the knowledge and competence of the workforce who’s managing and maintaining the assets.
- The asset strategy must define the requirements to be placed on the assets to support the business strategy. It’s implemented by a range of policies covering process safety, maintenance and inspection, renewal and competence.
- The three stages of an engagement are understanding the business strategy and asset management strategy and to undertake a high-level health check or gap analysis; the assessing and planning asset life with a four- or five-month study; and implementation, in which improvements are introduced to put the company on a better footing with respect to integrity, reliability and sustainability.
Many assets around the world are operating beyond their nominal design lives. The owners of such facilities face a common challenge: namely, how to maintain production capability in a cost-effective way while preserving the integrity of those assets.
A significant element of this is the need to develop an effective asset integrity management approach. Implementing asset integrity management requires that all the aspects of operations essential to safety and integrity are properly designed, constructed, tested, operated, inspected and maintained in a sustainable, holistic and systematic way.
The chosen approach must apply not just to the traditional interpretation of asset integrity management, focusing only on mechanical equipment, but also to safety-critical protective systems, electrical, instrumentation and control systems.
Industry dynamics and pressures
Industry, irrespective of the sector, is faced with the challenge of stakeholders’ increasing expectations and relentless economic pressures. This is compounded by the difficulties of managing an aged asset base; many were built and commissioned in the 1980s, 1970s and even the 1960s, and are still operating today.
Also, operating companies are increasingly sweating the assets — that is, operating existing assets beyond the original design life rather than building a new plant and tying up valuable capital. Indeed, many existing plants are now so far beyond their original anticipated operational lifecycle that design margins have been used up.
To try to gauge asset life extension, many companies have introduced initiatives to maintain integrity or improve reliability such as criticality assessments, risk-based inspection (RBI) and reliability-centered maintenance (RCM). However, installations may still suffer from significant unexpected failures and losses of containment. Such incidents include leakage from storage tanks and failure of non-critical pipework, degradation of coating systems and subsequent structural failure, despite an apparently good maintenance and inspection history.
Given such experience, it is not just mechanical systems and equipment that need to be addressed. Deterioration of instrument/electrical equipment and structural elements of the plant can also lead to an unacceptable situation, with damage to the plant, possible injury to personnel and loss of reputation or stakeholder confidence. Even if the condition of the equipment is preserved, obsolescence can affect the useful life of certain types of assets, notably control equipment and machines.
The integrity of the equipment is potentially further compromised by plant modifications and a history of operating excursions outside of the operating envelope. Other life-limiting deterioration can be caused by operating cycles and stresses exceeding the fatigue design life and the cumulative effect of operating for longer periods than assumed in the determination of the creep design life.
The process industries today face further challenges arising from other economic factors. Within the western hemisphere, there has been little significant investment in new plants while reduced refurbishment investments for existing plants has been the norm since the late 1980s. Pressures have been placed on maintenance budgets and resources to cut operation costs. Yet the industry is facing increased expectations from the public, employees and other stakeholders. This is particularly acute in the wake of a number of serious incidents around the world in recent years, which has drawn attention to the importance of continually improving the risk management requirements of hazardous plants.
Operators are increasingly realizing that achieving safety, reliability and plant integrity targets requires a holistic approach to integrity management. They are beginning to realize that safety, integrity and reliability are all linked. In essence, they are all manifestations of a management system that should be operating effectively to manage risk and yet achieve the commercial goals of the business.
Elements of an integrity management strategy
To develop a pragmatic integrity program, it is necessary to take into consideration all the relevant factors and to identify those where the business, site or plant can set clear and realistic targets. This is likely to be different for each company, taking into account such factors as the health, safety and environmental impact of losses of containment; production consequences of credible failure scenarios; design and construction pedigree of the assets; and plant upgrade plans.