Aerogel Academy

CUI can be difficult to locate, but we know that in order for CUI to be present, there must be the presence of water in a system. Many times you don’t know that CUI is an issue until something goes wrong—such as loss of containment, processes becoming unstable, or your personnel getting injured. After years of aiding customers in defending against CUI with Pyrogel, we offer the following tips for places to check for CUI in your facility.

1. Piping near or above open bodies of water, such as jetty lines.
2. Areas exposed to mist over-spray from cooling water towers, steam vents, and deluge systems.
3. Steam-traced systems, especially those insulated with water-absorbent, and/or rigid insulation materials.
4. Equipment in cyclic (i.e., operating both above and below the atmospheric dewpoint) or intermittent service.
5. Areas where proper application of surface coating is either not feasible, not guaranteed, or where coatings have degraded.
6. Areas subject to heavy foot traffic.
7. Tank roofs, especially those with sub-girt systems and fibrous insulation.
8. Pipe running through sub-surface road crossings.
9. Areas where moisture can pond, such as vertical pipe supports, valve bonnets, and insulation- and/or vacuum support rings.
10. Piping expansion loops, where the elbow jacketing tends to open up and fish-mouth.
11. At the bottom elbow of any vertical pipe run.
12. On horizontal equipment, the areas directly beneath any top-side penetration (nozzles, ladder clips, davits, etc.).
13. Sub-surface vaults where buried pipe systems are joined and valved.
14. Any pipe running within a trench or impoundment area.
15. Low points where the horizontal pipe is insulated with ill-fitting, rigid insulation.
16. Piping systems that have a tendency to move or vibrate, causing damage to insulation jacketing.
17. Top heads of insulated tanks.

How about you? Have you noticed an area more prone to CUI that others? Tell us about in the comments section below.

Need help preventing wet insulation, CUI, and process instability? Visit our CUI Defense Zone.

In this edition of the Aspen Academy Blog we are going to focus on snakes. Yes, great big, venomous, dangerous snakes—the kind that can ruin your day.  You’re probably asking yourself, “What could snakes have to do with thermal insulation?”

Quite a lot, it seems. At the 2009 AIChE Spring Meeting and Global Congress on Process Safety, J.B. Prows delivered a paper¹ that addressed the jet fire event at the Huntsman Petrochemical plant in Port Arthur, Texas. Corrosion under insulation (CUI) due to persistently wet insulation was identified at the primary cause of a catastrophic fire in the Light Olefins Unit. The cost of reconstruction exceeded $300m and took 14 months to complete.  The author likened the potential defects caused by CUI to rattlesnakes, which prompted the title Killing Rattlesnakes Before They Bite You.

The metaphor is not lost on the team at Aspen Aerogels. Our Pyrogel high temperature insulation is engineered to provide superior CUI defense, and is required to meet or exceed a host of test standards. So it was with a sense of great satisfaction that we added a new criteria to our qualification—Pyrogel is snake-safe.

Engineers, by nature, are proactive in their quest to improve the processes, systems, and designs that they work on daily. But, looming deadlines and budget constraints often mean that you make insulation choices without added consideration. Are you choosing insulation because it’s what was already in place and that’s good enough for now?  We’re not knocking that approach; we get it. However, if you’re looking for long term solutions for problems that plague your insulation systems­­—including CUI— we think it’s time to ratchet up your proactive ways and make a different choice. So, let’s talk about that.

Corrosion under insulation can only occur in a wet environment. The implication of wetness on insulation selection is well summarized in section 2.1.2.1 of NACE Standard SP0198 Control of Corrosion Under Thermal Insulation and Fireproofing Materials:

“Because CUI is a product of wet metal exposure duration, the insulation system that holds the least amount of water and dries most quickly should result in the least amount of corrosion damage to equipment.”

In both hot and cold service, non-wicking, non-absorbent insulation is often the preferred material choice. No one wants their insulation to get wet—wet insulation is truly one of industry's contradictions. Yet, today, many facilities continue to use outdated, water-absorbing insulation, putting their processes and profitability at risk, and their assets and risk for CUI. 

It’s a conundrum, for sure. But Pyrogel offers something that proactive engineers are relying on more and more.

Many of you know that Aspen is based outside of Boston and, of course, it is a time for celebration as our beloved Boston Red Sox won the World Series just two nights ago. While we’re enjoying this championship and the fanfare that comes with it, what’s truly inspiring to us is how the team’s preparation and planning led to the ultimate win. The Red Sox won because of their game plan. They were prepared to face the toughest of teams, situations, and challenges. That’s what we do every day at Aspen—we help industrial organizations plan and prepare to keep their assets performing optimally with world-class insulation that prevents Corrosion Under Insulation (CUI).  

The weight of insulation is becoming increasingly critical for today's congested industrial sites. For some sites, turnaround and maintenance schedules can be negatively impacted by space and weight limitations—just think about the use of cranes where space is restricted as an example. In this post, we focus on the weight of thermal insulation, including when it becomes an important consideration for refinery and chemical processing engineers.