Heat exchangers are an inevitable element in any process industry and therefore keeping it clean is important.
The shell and tube heat exchangers used to be cleaned using Ultra high-pressure waterjet (UHPWJ) usually for several years. Considering the risk involved and the limitations in setting up the machines, clearing safety audits, the space it occupies, UHPWJ is not a safe option for cleaning heat exchanger tubes. Again, localized cleaning inside the tubes may not be possible with this technique besides the time it takes for the entire procedure. Here comes the safest alternative which takes no time to set up and to clear the safety audit by the HSE department to issue the work permit.
Mechanical offline cleaning using TruFitTM cleaners is the best option as a safer alternative for high-pressure water jet cleaning as it ensures better cleaning at no risk. This methodology works at low pressure to the tune of 20-30 bar using water and custom-made cleaners that fit exactly the inner diameter of the tube. The cleaners are manufactured by CONCO Systems, USA, the pioneers of mechanical offline cleaning technology since 1923.
The advantages of this cleaning are
- The cleaning is more localized, using water and customized cleaners
- It won’t cause any serious risk to the operator
- It takes less than half an hour to set up
- It takes less space, a maximum of 5 SQM
- It takes less time to clean a bundle in-situ compared to any other method
We experience from plant maintenance technicians that, the UHPWJ doesn’t even help to get IRIS results due to the scales inside even after cleaning. Mechanical cleaning by TruFitTM ensures better cleaning bringing the tubes to its original cleanliness and ensures a legible IRIS result. Our experience is that our customers are more relaxed and happier if this methodology is being used for their heat exchanger cleaning.
The question that remains with the maintenance team is that what if any cleaner gets stuck inside? The answer is, the operators are trained not to insert any cleaners without having sufficient water pass through individual tubes. The tubes are cleaned with water and inspected prior to inserting the cleaners. However, there are chances to get the cleaners trapped inside. The operators have different practical techniques to retrieve those cleaners. They also use fiber rods if in case other techniques fail. The field team consists of one technician and one standby technician, one tally counter cum operator, and a Supervisor. The tally counter takes all the cleaners back, count and log immediately after shooting it through the tubes. Therefore, the Supervisor and his team won’t miss any cleaners inside. The procedures are well defined and followed by the team.
The recent experience with Qatar Gas shutdown was great as we could get back clean tubes, clear IRIS readings, and better heat transfer parameters once those exchangers are back in operation. We have cleaned one exchanger in one shift, though those exchangers are not cleaned for long and achieved desired results.
For more information on mechanical offline cleaning, visit our website service page, and Conco Official Website https://www.concosystems.com
Or contact us walco@walco.qa or call Engineer, Joel Varghese +974-33838023
