5 Ways to Improve Critical Valves' Reliability

Author : Dave Anderson, April-2021

Anyone who owns or is involved in the operation of a fluid process will be aware that that valves play a critical part in their safe, efficient and reliable operation.

Given this critical role, we understand that it is imperative that the operating performance and reliability of these devices is maximized at all times. Furthermore, we appreciate that this requires a level of attention and continuing investment - not just in the initial purchase of each valve asset, but over the whole life of individual valves and the processes they are installed in, to ensure the required operational performance standards continue to be met over each asset’s installed life cycle.

From a safety perspective, operators must verify that all installed valves are capable of fulfilling their intended safe operational function(s). This ensures the protection of people, process and plant. Safe operations are already highly regulated in many markets worldwide.

In terms of achieving best environmental stewardship, operators must maintain and provide evidence that optimum clean operating standards are being met, at all times. This is increasingly under scrutiny worldwide as the reduction of carbon and other emissions are being brought into sharp focus and are subject to compliance requirements.

The management of risks associated with critical failure in service and continuing performance over time are therefore paramount.

Sound governance and management practices are always to be encouraged to maintain valve assets and, in some instances, have become mandated to achieve at least a prescribed minimum operational performance. Regulatory requirements, as well as recommended practices have been introduced to manage this position by various key organizations around the world such ISO, EPA, ISA, BSSE, HSE, CEN, WIB and IAM, to name just a few. However, the question many organizations and their insurers are now asking is – do these minimum compliance requirements / standards adequately manage our exposure to risks?

Having worked in the valve industry for 37 years, my experience is that process industries could still be investing more in improving their valves’ reliability and if they have an appetite to do so, then they need good advice on exactly what to invest in and what is likely to make a significant impact on the reliability of their valves in service.

Taking a very simplistic view, I believe that valve reliability can be improved in the following 5 ways :-

1.      Design for Reliability

This is about making sure, at the front end engineering design stage for any process, that we fully understand the operational process criteria, the inherent risks of in-service failures and the performance requirements of each valve asset that shall be installed in that process. In a new-build situation, this is of course easier to manage than when working in an existing brown-field plant. 

 We must avoid generalizations in valve specification or the one-size-fits-all approach and take a very close look at the specific requirements to ensure we select the correct design and performance specification for each and every valve in service. Mitigation of in-service performance risks through optimized design specification is key. It is accepted that the potential compromise between quality and costs are inherently linked, however, very small design changes can significantly change in-service reliability and life expectancy of valves. Whole life costs must always be considered (including the potential for losses resulting from in-service failures), but we must also guard against "gold plating" - so a balance needs to be struck.

 2.      Build and Verify Performance (Benchmark) for Reliability

In addition to industry recognized “type approval” testing programs (such as ISO 15848-1, PR2, etc.), immediately following the completion of the manufacture of each valve, a set of prescribed tests are applied to verify the “as built” performance of the valve / automated valve assembly. These factory acceptance tests principally look at the functional capabilities of valves from a fluid containment and flow manipulation perspective.

 Are these the only measures that carry risk? Do we measure and verify all the appropriate performance criteria? Are there additional “as-built” tests that we should be carrying out? To simply complete a factory acceptance test which may bear no direct resemblance to the expected operating / service conditions would give very limited reliability confidence. We must define and implement appropriate enhanced testing that best manages and mitigates the risk of critical in-service failures. Valve purchasers will likely request new and enhanced testing procedures moving forwards.

 3.      Monitor In-Service Performance for Reliability

A wide variety of specialist sensor devices and systems are available in the marketplace for in-situ monitoring of the actual in-service performance capability of valves. Each has its own unique features, benefits and limitations. Such equipment should be focused on the failure mode it is trying to predict or report. Not all organizations have invested in these monitoring equipment / systems and capabilities to date.

When we monitor valves in service, it is of critical importance to select the correct monitoring equipment and systems and this selection process should be inherently tied to the probability and consequences of the failure mode it is focused on finding / reporting within the valve / automated valve assembly. The correctly selected and deployed monitoring equipment and systems should give clear indication of potentially developing failure modes at the earliest possible time, so that maintenance can be carried out well in advance of the in-service failure event, thus mitigating risk and potential for losses.

4.      Maintain for Reliability

With the wide adoption of computerized maintenance management systems, many companies are increasingly dependent upon and locked into “calendar based” maintenance routines. These routines can be anything from the recurring installation of spares on a “just-in-case” basis, through to the more “preventive” type of maintenance routines which are carried out periodically, to manage risks – sometimes in an arbitrary way. Unfortunately, some of these actions can be contributory to in-service failures and so reduce reliability rather than improve it. 

We must refocus our available maintenance resources on a more evidence-based prioritization basis, where we use the actual field performance data to drive maintenance decision making and interventions moving forward. When we see specific indicators of developing failure modes, we will be in a position to consult on the recommended recovery practices and focus on value-based maintenance.  

 5.      Performance Review and Re-Engineer for Reliability

When running a process over time, random, recurring or systemic failures can emerge. Simply replacing valve assets on a like for like basis when historical failure data is available does not make commercial sense.  The diligent and complete recording of in-service failures by the operating company can flag up where investment may have a positive impact on improving valves’ reliability. This is however very often under-exploited as an opportunity because the management of change process is over-complicated or challenging. 

We must avoid the constant merry-go-round of recurring failures. With every in-service failure comes a gift of learning that presents itself. When effective root cause analysis work takes place, longer-term reliability improvements can be realized by re-evaluating the engineering design requirements for the replacement asset. Each subsequent re-engineering exercise, resulting from in-service failure data and findings must be designed to maximize future in-service valve reliability. This effectively closes the loop on our virtuous cycle of continuous improvement when joined back to point 1, above. 

I am aware of (and we are in Score Group currently engaging on differing levels with) five industry groups who are working with the best available manufacturing leaders, historical in-field performance data, visionary thinkers and major valve users / operating companies in the marketplace, to collaborate and improve automated valve reliability for the benefit of all stakeholders.

These groups are supported by recognized international standards development organizations, specialist technical consultants and valve owners / process operators. Each group has their own key focus on where they believe they can have the biggest potential impact on improving reliability. In reality, all are doing some fantastic contributory work, although to my knowledge, none have yet published new mandatory compliance standards in any markets.

I firmly believe that we must change the ways in which we work as an industry if we are to succeed in delivering the improvements all stakeholders are eager to benefit from. We are still having discussions with some operating companies whose policy on valve maintenance is “run to failure” – i.e. the highest possible risk potential environment to work in. These same companies continue to report losses relating to in-service failures that they would rather not experience. 

We all must truly commit to improving this situation and be prepared to disrupt old ways of working - as Albert Einstein once said, doing the same thing and expecting different results is the definition of insanity... so let’s start implementing something different and better now.

The only way the valve industry will improve the reliability of valves / valve assemblies over time is to engage in implementing the new recommended practices, technical reports and operating standards being designed and developed right now. The wider the collaboration, the better chance we all have of reaching as close to 100% reliability in our valve populations performance as possible. Whilst the initial / short-term investment costs may marginally increase, we can expect the long-term total costs to be significantly lower as we see less effects and impacts of much more expensive unexpected in-service failures.

I am happy to help support and champion this outcome moving forward and would be happy to share more on this subject with anyone who would like to join forces to make change happen. Let’s collaborate to win!

For more information or to take the discussion further, please feel free to contact us at e-mail: [email protected]

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