Heat Exchanger Cleaning

Scope of Work

Stork was contracted by a major UK-based operator to complete specialist cleaning works on six heat exchangers which were operating at reduced capacity on an offshore asset in the Irish Sea.

Upon investigation of the tube bundles, it was noted the external shell was clogged with solidified scales and the tubes had partial blockages due to wax and scale build up, which ultimately led to an impact on production.

Tube bundles explained:

Tube bundles are located inside shell and tube heat exchangers. The tube bundles are positioned within a cylindrical shell, where fluids at different starting temperatures (either liquids or gases) pass through and over tubes.

Stork's Approach

Conventional retro-jetting didn’t provide the desired end result. Therefore, Stork’s team of experts re-assessed the scope and altered the methodology to tackle the challenge. This ultimately ensured our client’s expectations were met. The deployment of specially selected jets were utilised to remove the hard scale. A jet centraliser was used to protect the jet as it passed through the vessel internal shell, centralising the jet extension arms to a stand-off distance for a more consistent clean.

A 3-man multi-discipline team was mobilised to execute this scope of work. Through use of bespoke jetting techniques, the team cleared the tube bundles and shell of scale and debris to allow for an Internal Rotary Inspection System (IRIS) inspection to take place.

The Outcome

• Before starting the job, all worksites were safely set up with bunds, which were erected to contain all liquid and debris
• All Stork personnel were suitably qualified, along with certified plant and equipment to carry out the scope of work without delay
• Work was carried out with a safety-first approach and as a result, no accidents, incidents or injuries occurred
• The six heat exchangers were cleaned to the client’s satisfaction and back up to full working capacity