Case Study of Full-Length Tube Coating and Condenser Life Extension

In the Spring of 2012 a 1950’s vintage natural gas unit located on a lake in Texas encountered multiple condenser tube failures of its Admiralty Brass tubes. Due to time and cost restraints, the option of retubing was not chosen to prepare the unit for the summer run. Instead, the full-length of approximately 5,500 tubes were epoxy coated. This included 1,150 tubes which had been plugged as leakers, but were unplugged and coated using a special leak sealing method of applying the epoxy lining. The coating process was completed in 10 days and all but 55 tubes were sealed by the coating process. These tubes were plugged and the unit was put into service. The unit has been running successfully since the project was completed with no heat rate penalty. The circumstances leading up to this situation are discussed along with the details of the coating process.