ProRox Mat (Wrap) Insulation Optimizes Plant Maintenance Costs by Keeping Corrosion Under Control

Photo Courtesy of ROCKWOOL

Corrosion under insulation (CUI) is a pervasive challenge in many insulated plant processes, thanks to the ingress of water through the insulation and onto the metal surfaces of steel pipes, vessels, columns, and other plant equipment.

Effectively mitigating CUI and keeping plant equipment running effectively is an expensive and time-consuming exercise for a plant’s maintenance crews. CUI accounts for an estimated 10% of a plant’s overall maintenance costs and up to 60% of pipeline maintenance costs.  And when one factors in the downtime accrued while making repairs, it becomes evident that CUI can have a significant impact on increasing a plant’s overall operating costs, thus hindering its profitability.

Effective CUI Protection for Plant Components

For decades, ROCKWOOL Technical Insulation has focused its research and manufacturing efforts on leveraging stone wool’s excellent thermal properties to develop insulation solutions for industries on both land and at sea. ROCKWOOL’s expertise lies in manufacturing and applying a wide range of insulation systems with stone wool as the base material. The company’s core focus on natural insulation has made it one of the largest manufacturers of stone wool insulation in North America and globally.

The company has continued to design new stone wool insulation innovations as industry needs continue to grow in complexity and scope. Recently ROCKWOOL developed a technology solution to effectively mitigate CUI, while delivering required insulation performance, for large-diameter pipework, vessels, columns, and applications where design flexibility is needed. The next-generation ProRox MA 961 is a rolled, stone wool insulation mat (wrap) designed for application on plant equipment with a wide variety of geometries and sizes.

The ProRox MA 961 is the latest offering in ROCKWOOL Technical Insulation’s line of ProRox stone wool insulation products. It effectively combats CUI by reducing water absorption within the insulation using a revolutionary water-repellant binder technology called WR-Tech. This unique, patent-pending formation is coated on individual fibers of the ProRox insulation to provide excellent hydrophobic performance throughout the material.

WR-Tech gives the insulation dramatically improved water repellency to help decrease the duration of wet metal exposure. Extensive testing has shown that the patent-pending WR-Tech makes ProRox insulation five times more water repellent than standard EN-compliant stone wool, even after heat aging.

ProRox materials maintain their superior water repellency, even after pre-heating at a sustained temperature of 482°F/250°C for 24 hours. This testing criterion is one of the most stringent and severe in the industry.

ProRox materials also help lower a plant’s total cost of operations with their ease of application—no glue is required and fewer layers are needed to achieve the same thermal insulation properties as other materials—allowing for shorter installation times.

WR-Tech’s effectiveness at mitigating CUI has been recognized by the industry, including NACE International’s Materials Performance Magazine. The magazine awarded the technology a 2019 Corrosion Innovation of the Year Award. WR-Tech was one of 10 technologies out of more than 50 nominees to receive the coveted award, thanks to its growing track record of significantly advancing corrosion control in plant settings.

Comprehensive CUI Solution

WR-Tech was first successfully launched on ROCKWOOL’s ProRox mandrel wound pipe sections, where it quickly proved its value in combatting CUI in several piping applications. Soon customers were requesting WR-Tech in flexible mat (wrap) products to address CUI in an even greater number of applications. ROCKWOOL listened, and now engineers and owners are upgrading their specifications to include high-performing CUI solutions with WR-Tech, while contractors and installers are frequently applying ProRox products to both new-build and maintenance projects.

With WR-Tech as part of ProRox MA 961, complex equipment designs and complete pipeline systems—including bends—can now be protected from the hazards of CUI. The result: safer plant operations, reduced environmental impact, lower total maintenance costs, and greater potential for improved plant performance and profitability.

Source: ROCKWOOL Technical Insulation,