SCM trademarks external corrosion degradation-rate formula

Strategic Corrosion Management has announced the trademarking of degRATE – the company’s unique and pioneering Semi-Quantitative Substrate Degradation Assessment calculation - which generates the rate of external corrosion degradation on plant substrates.

degRATE could precipitate a huge “paradigm shift” in the way that corrosion maintenance work is planned and scheduled across a range of industries. In adopting the degRATE methodology, plant operators will finally achieve cost effective maintenance centred around their most appropriate priorities.

Work on degRATE effectively started back in the late 1980’s, when Strategic Corrosion Management developed the world’s first external corrosion management toolset and procedures. The goal then was to streamline corrosion protection planning (coatings and insulation) for on and offshore operators. One of the (many) challenges the industry faced at that time, attributable to the rapid expansion of offshore production fields and the manufacturing of new rigs, was a shortage of skilled personnel capable of undertaking the necessary work of corrosion prevention. The SCM process tools, for example ‘Project Paint’ software, helped operators to not only identify where maintenance was essential but also to reduce it (and associated costs) to the lowest acceptable level through the prioritisation and sub-prioritisation of maintenance workloads.

The science of how to make those decisions, however, was still in its infancy, and the process was often seen as a guesstimate, rather than a logical methodology. In 1987, the same year Project Paint was first deployed offshore over 14 Shell Southern assets, it became apparent that there was still a requirement for a method that would offer full visibility of plant corrosion condition, and in 1990 SCM created the SCFM (Substrate Condition and Failure Mode) scale, which combined the ‘European Scale of Rusting’ (Re Scale) and added an understanding of the ‘type’ of corrosion protection failure and the ‘mode’ of that failure.

Until now, applying these scales, and attempting to reconcile the expected degradation with Integrity Inspections and Anomaly Reports, has been the most effective way of planning corrosion maintenance. Using these ‘coarse’ rates of degradation (RoD) assessments has allowed for more flexible maintenance plans to be implemented than was previously possible however, it has always had a major failing – as with the RBA process (Risk Based Assessment), it works on the premise that corrosion degradation is uniform across an entire plant.

degRATE calculates specific rates of external corrosion degradation on all plant substrates (pipes, valves, vessels, structures etc.) and it does this by applying a unique ‘weighting’ for every separate impacting factor on the basis that every component (or component part) is in a ‘unique’ micro-climate and conditions of influence and therefore has its own individual rate of degradation. The RoD depends on many influencing factors such as metallurgy, operating temperature, coating specification, insulation specification and ambient conditions.

degRATE takes account for up to 15 separate impacting factors – each with sub-sets of their own, all of which are defined by SCM as “Semi-Quantitative Substrate Degradation Assessment Factors”- SQSDAF for short. These factors have been applied within the company’s holistic corrosion, maintenance & integrity technology suite ‘360integrity’ for some time. Now, as degRATE, the process becomes available by license to the operators of all types of process plant.

In a recent case study degRATE delivered almost an 80% reduction in the anticipated annual maintenance load for one client on several assets. This resulted in, not only less maintenance work being required, but a massive reduction in personnel, materials and equipment resources, not to mention less downtime and a reduced impact of plant isolations during maintenance.

degRATE influences the entire maintenance decision making process. Once the operator understands the current condition of all components (an assigned classification based on current condition per an SCFM or RE-based scale) degRATE facilitates range of simple and complex analyses, otherwise not possible, such as fabric condition projections and maintenance deferment analysis. Such tools contribute to the delivery of complete visibility of plant condition, potential integrity threats and objective evidence of corrosion control, now and into the future.

Managing Director at Strategic Corrosion Management, Ian Cordingley, said:

“This is a massive landmark for us at SCM. Our goal with degRATE is to change the way that corrosion maintenance work is planned and scheduled across a range of industries, which is no mean feat. In adopting the degRATE methodology, plant operators will finally achieve cost effective maintenance centred around their most appropriate priorities.

We want to support and guide industry professionals away from that dangerous phrase ‘because that’s the way we’ve always done it’ and join us in adopting this new methodology which we believe can inspire a monumental change in industry, at a time when it is perhaps most needed.”

To find out more about degRATE, visit the SCM blog page where products and services division coordinator, Marc Dabbs, shares further insight into the process.

References 360integrity, degRATE, Fabric Maintenance, Objective Evidence, Deferment Analysis, Fabric Projections