Designing Systems to Handle a One-Off Water Intrusion Event

We’ll Be at the NACE Corrosion Risk Management Conference and Presenting on Hydrophobic Insulation - You Don’t Want to Miss This! On May 23-25, Johns Manville Industrial Insulation Group will be exhibiting (#113) at the NACE Corrosion Risk Management Conference in Houston, Texas, where our own Professional Engineer, Doug Fast, will be presenting the details of his white paper, “Piping Insulation System Design to Tolerate a One-Time Challenging Water Intrusion Event” on Wednesday, May 25th at 1:15pm. Doug’s paper answers one big question – how do you design a system that can handle a one-off disaster, such as a storm surge from a hurricane, where water infiltrates the jacketing and the insulation system? When it comes to water infiltration in an industrial insulation system, one thing is certain: water always wins. Given the sheer size of industrial facilities, it would be nearly impossible to protect all the linear feet of outdoor, insulated piping systems from water intrusion. Unnoticed mistakes in installation, flaws in the jacketing, and impact damage make it extremely difficult to ensure that each foot of insulated pipe remains safe from water ingress. However, given that keeping water out of the entire system 100% of the time is a losing battle, what can we do about it? While we can assume that a properly jacketed and insulated piping system will provide sufficient resistance to mostbulk water entry, extreme and unexpected weather conditions can bring out the flaws in less than satisfactory jacket detailing. This can allow the system to become wet, diminishing thermal performance and introducing the potential for corrosion under insulation (CUI). The safest way to design an insulation system to handle a one-off water entry event is to assume that water ingress is an eventuality and not a probability. By approaching system design with this mentality, designers will be starting from a defensive position before CUI even becomes a threat. There are a number of factors that play into designing systems that can tolerate water exposure, ranging from specifying the right insulation to ensuring that metal jacketing is properly installed and detailed over the insulation. While choosing the jacketing is pretty straight forward, when it comes to choosing the insulation, there are several features that system designers should consider:

  • Whether the insulation absorbs water (hydrophilic) or inhibits water absorption (hydrophobic)
  • The presence of corrosion inhibitors in the insulation
  • The insulation’s ability to allow moisture to pass through it

These are just the high-level issues that need to be addressed, but as we start to look at the system as a whole, it becomes clear that there is more at play than just the insulation’s features. To learn more about designing systems that can withstand a one-time water intrusion event, attend Doug’s presentation at the NACE conference in Houston on May 25th at 1:15pm and visit our booth (#113) where Doug will be available to answers questions. We also invite you to stop by to meet our new Gulf Coast Specification Representative, Larry Johns. Following the NACE conference, you will be able to download the white paper directly from the website.