How Advanced Conduit Sealing Protects Power Transmission …
We talk a lot about what it means to facilitate operational resilience that prevents issues and outages across energy ecosystems that can span entire regions. While such larger issues can be caused by a myriad of factors, they often stem from much smaller ones at the entry point for substation equipment and transformers. These essential pieces of infrastructure are as robust as they are capable, but they’re ultimately only as reliable as the seals that protect them.
During the recent Engineering Safer Substations: Design and Retrofit Approaches to Risk Mitigation webinar, Roxtec’s Jim McElgan and Ryan Groff broke down how advanced sealing technologies can serve as a foundational element of an all-encompassing grid resilience strategy. They challenged the “adequately sealed” mindset by illustrating the vulnerability of infrastructure that relies on the bare minimum. McElgan and Groff further highlighted the hidden risks of this sort of approach, providing a roadmap for teams looking to protect both individual assets and larger energy ecosystems.
The Hidden Hazards of Traditional Sealing
Common industry practices often rely on solutions spray foam, duct seal, or putties that are relatively easy to find in the field. For the most part, they’re designed to and can work on something a residential shed, but they simply can’t hold up to the rigors of energy infrastructure.
Spray foam can cause complicated issues since it’s quick to install but nearly impossible to maintain. Removing aged epoxy or foam to add a new cable often results in damage to existing lines and hours of wasted labor. Rodents can also chew through foams and putties, leading to arc flashes and equipment failure in ways that are as unique as they are universal. Roxtec compresses rubber modules within a metal frame and have operating temperatures between -76F to +176F, which has proven to be a barrier for rodents that can otherwise create countless problems.
“Rodents have a way of chewing through things the foams to make their way in,” said Groff. “They just cannot physically chew through this rubber when it is compressed to this degree to actually get into your equipment, and we do have proven tests to show that.”
By moving away from materials that are easy to find, and instead utilizing compressed sealing systems, teams can eliminate preventable points of failure. In doing so, they’ve been able to reduce maintenance hours and ensure that their most critical assets remain resilient in a way that’s measurable.
Understanding the Roxtec Multidiameter solution
The core of Roxtec’s modern sealing technology is Multidiameter, which is a system of modules with removable layers. This allows a single module to adapt to a wide range of cable sizes, ensuring an ideal 360-degree fit.
“We have six different module sizes, from 1/8 of an inch to just under 4 inches,that are covered by those six module sizes,” said Groff. “Most of them fall into the middle range, and I’ll go step by step on what constitutes a system.”
Groff detailed how the system begins with a frame based on the specific application, whether it be a wall, cabinet, or underground entry. The modules act industrial building blocks that peel away to fit the specific cable diameter. Stayplates are then inserted between rows to ensure structural integrity and prevent bowing under pressure. The final component is the wedge, which compresses the entire system to create an airtight and watertight seal.
“Globally local” to address any need
Modern infrastructure needs more than just a physical plug, which is why Roxtec solutions offer specialized protection across several categories. For fire safety, Roxtec rubber is UL 1479 rated, providing up to a four-hour fire rating for wall and floor penetrations. In HVDC converter stations, bonding and grounding modules ensure electromagnetic shielding and safety against EMI or EMP. Underground solutions are designed for constant water pressure and can even be installed in running water conditions, which is a lifer for flooded manholes or basements.
While these hazards vary by site, they are all addressed through a core Roxtec value that McElgan describes as being “globally local” in the context of the Roxtec R frame. “That’s one of our core values. Because wherever you are, everyone has a different issue. This client needed a bus bar for water ingress going into the basement. We have a water jet in Tulsa, Oklahoma, where we got the measurements of the bus bar and created a module to fit around it so we could do unique applications based on the rubber.”
These customized solutions are especially valuable for retrofit projects. Because Roxtec uses openable frames, modules can be installed around existing cables without the need to disconnect or de-terminate, saving thousands in labor costs. This versatility also extends to substation control houses, which typically utilize waterfall configurations and cover plates to allow for future growth, meaning new cables can be added by simply loosening the wedge without any drilling. For marshaling cabinets, custom-designed plates can be manufactured via water-jet technology to fit any cabinet footprint, providing a clean, rodent-proof entry.
Why “adequately sealed” will never be enough
That’s just a brief look at the insights McElgan and Groff detailed in a visually dynamic presentation. The webinar also included an interactive Q&A that explored specific challenges for cabinets, enclosures, control room wall entries, and underground conduits.
Whether it’s measuring entries from a ladder in the Midwest or designing off-center seals in the Northeast, keeping infrastructure at its best regardless of the environment or application allows utilities to enable reliability in a way that’s truly measurable. All of it underscores how and why transitioning from “adequately sealed” to true “engineered resilience” needs to be a focus for utilities of all sizes.
Register now and watch the free, on-demand event, Engineering Safer Substations: Design and Retrofit Approaches to Risk Mitigation