Power transformers are one of the most important and expensive assets in a power network. In general, they are very reliable and require little maintenance The insulation materials of most power transformers degrade with time in service, and ultimately determine the end of life of the transformer. They consists of organic materials…Mineral oil, cellulose paper, and pressboard. Moisture in the insulation system, along with operating temperature and oxygen in the transformer oil, constitutes the most important transformer insulation aging mechanism. Maintaining transformer insulation in a properly "dried-out" state to reduce the aging phenomenon and the risk of failure can be a difficult and costly process, requiring capital-intensive equipment and significant transformer outages.

Revolutionary Technology

DryKeep is an on-line molecular sieve insulation dry-out system that will continuously remove water from the oil and paper insulation in power transformers. The process not only reduces aging but will improve the dielectric strength of the paper insulation. It was developed by the Power Distribution Services (PDS) business unit of Rotek Engineering, in collaboration with the Nuclear Energy Corporation of South Africa(NECSA). PDS is the largest power transformer repairer in sub-Sahara Africa. It is 100% owned by Eskom, the national electricity utility of South Africa.