How do you repair a 300mm wide split in a discharge pipe whilst 2000 litres of water is constantly forced through the crack every minute?  You Belzona It!

The AESSEAL team in Richards Bay was faced with a huge challenge at one of their customers’ sites: 2 x 700mm diameter discharge pipes supply water to two furnaces to keep them cool at all times. The lobster bend on the discharge of the second pipe was leaking on the weld, and the customer had tried to use a bandit strap with some insertion rubber to minimise the leak. This was only a temporary solution, as this leak proved to have too many complications that came with it.

Complications

Firstly, the water supply feed requires 2000 litres per minute per furnace in order to keep the furnace regulated at a certain temperature. The water supply cannot, under any circumstance be turned off as the furnaces will solidify. If this happens, two complete furnaces will become rock solid and will have to be replaced, costing hundreds of millions of Rand’s.

Secondly, these furnaces only come down every 2 years, and when it does go down, it takes 1 – 2 weeks to slowly cool the furnaces down, whilst emptying the entire product out of each furnace. With the plant not being ready for a shutdown, the repair had to take place whilst running at 2000 litres of water per minute.

Lastly, if the lobster bend burst completely, the sump of 50m x 30m x 10m, with 8 pumps inside, would completely be filled with water in 4 minutes! This excludes the massive electrical short that would take place on this plant.

The AESSEAL team was told that the leak was about the size of a R5 coin, however, after closer inspection it was found to be a 300mm wide split on the weld, and not a small hole, which further complicated the repair!

Plan of Action

AESSEAL had a 10mm bolted saddle with rubber lining made up. It took the team, including 3 of the customer’s artisans over three hours to install this saddle. Their biggest challenge was to get it fitted whilst fighting off the high water pressure.

Before the Saddle Installation

After the Saddle Installation

Once the saddle was installed, it took the team another 3 hours to torque it up to try and get the rubber insertion inside the seal around the pipe – however, it was still leaking at the top and bottom, which meant the job wasn’t finished just yet.

The next day the team began sealing off the entire saddle with Belzona 1212 and 1111, using the Belzona 9341 Membrane as reinforcing. 45 kg’s of Belzona was used for this repair. The Belzona 1212 (surface tolerant) was used for all the wet areas, and the Belzona 1111 was used for the dry areas.

During the Belzona Application

 

Final Result

Saving to the Customer

The saving to AESSEAL’s customer in downtime, excluding the loss of 2 furnaces which is hundreds of millions of Rand’s, was a massive R2.5 million.