Revitalising efficiency: Technowrap™ SRS HT repair for waste heat recovery unit roofs

Three waste heat recovery unit roofs faced extensive external corrosion, leading to through-wall penetration in some areas and wall thinning in others. Our client needed a solution that would effectively reinstate the integrity and reinforce these roof sections, aiming for a 20-year repair lifetime. The challenge was compounded by the operating temperature of 220°C, requiring a repair method that could withstand the relevant loads and operate efficiently at elevated temperatures.

We provided an engineered design for a 20-year repair lifetime, deploying Technowrap™ trained personnel, and utilizing Technowrap™ SRS HT carbon fiber materials for the repair. Given the severity of corrosion and the client’s preference to avoid grit blasting, ST3 Mechanical Preparation and ST2 hand preparation were used to achieve suitable surface finishes for bonding without causing further damage. To address the more severe corrosion than initially anticipated, wire mesh fillers were implemented and cured before the installation of the engineered Technowrap™ repairs. The operating temperature necessitated a temporary reduction to facilitate repair installation, with the heat from the units aiding in the curing process and reducing installation time.

Technowrap™ Structural Strengthening carbon fiber was meticulously applied using the hand lay-up technique, ensuring precise sizing of repairs and incorporating a slight taper at the edge of the panels.

The repairs were executed seamlessly while the units remained live, eliminating the need for isolation or shutdown, thereby preventing any loss of operation or production. The successful application of Technowrap™ SRS HT showcased its adaptability to high-temperature environments, offering a durable solution for waste heat recovery unit roofs.