How to Stop and Repair a Live Leak

Live leak and through-wall defects are quite common when it comes to the maintenance and repair of tanks and pipes. External and internal corrosion, aggressive chemicals and tough operating conditions contribute to the metal loss and wall thinning. Lack of prevention or timely maintenance might lead to delays in production, leakage of hazardous materials, and health and safety hazards. While conventional methods, such as welding and brazing, have historically been widely used to carry out the repairs on tanks and pipework, they lead to some consequential problems: bi-metallic corrosion in welds and seams, downtime, environmental damage, and hazardous conditions for the equipment and maintenance personnel.

In our previous block post “How to Repair a Cracked Engine Block”, we already demonstrated an application with cold-applied epoxy-based Belzona 1111. In this blog post we again demonstrate how Belzona’s cold-applied repair composites and cold bonding techniques make such repairs an excellent alternative to welding and other types of hot work. You will learn how to stop a live leak, and reinforce the thinning structure of a tank without taking it out of service, damaging its external/internal structure, or creating a hazardous environment for the personnel.

To carry out a live leak repair and to reinforce the structure of this tank, we used Belzona 1161 (Super UW-Metal), Belzona 9611 (ES-Metal), Belzona 9111 (Cleaner/Degreaser), a preformed metal plate and a few tools from our machine shop. First, we had to stop the flow. After thoroughly cleaning the surface around the damaged area, Belzona 9611, a fast curing paste grade material, was carefully kneaded and forced into the through-wall defect. A 2″ x 4″ stud and a Ratchet strap were used to secure the material in place until it fully cured.

For the reinforcement of the damaged area we used a preformed metal plate and Belzona 1161 as a bonding agent. The damaged areas on the tank as well as the mating face of the preformed plate were roughened using a grinder. Both substrates were then washed down with Belzona 9111 to remove all dirt, grease and other contaminants. Mixed Belzona 1161 was applied to all the prepared areas (on the tank and on the plate) and worked well into the roughened profile with a short bristled brush. While applying the mixed product onto the metal plate we created a build up (approx. ¼” (6 mm) thick) towards the center. This allows for displacing air while positioning the plate onto the tank wall. The plate was then pushed into position and forced down until Belzona 1161 exuded on each edge of the plate. The exuded material was immediately removed and used to chamfer the edges.