Fire protection of oil filled transformers and reactors: Nitrogen gas based explosion prevention and fire extinguishing system

Protection of critical assets such as transformers, reactors have been used for decades now. Starting from the early water based hydrants to today's nitrogen based explosion prevention and fire extinguishing system, the reliability of the system has increased manifold. Earlier systems mainly did the function of extinguishing a fire after the transformer had been ignited. They were directed more to ‘containment of the spread of fire’ in the substation, and preventing further damage to healthy apparatus in the substation. Systems such as mulsifier system, carbon dioxide system, watermist system were not capable of extinguishing the fire effectively, let alone preventing an explosion. They all operated after the transformer had totally failed, partially exploded and the fire is visually noticed externally. They were slow to react and many times did not contain the flame. They never protected the failed product, but only attempted to protect the other components in the substation. They had limitations such as their nozzles getting quickly clogged by sand/dust/calcification; need for regular cleaning and need for periodic maintenance shut down of the transformer. Nitrogen based Explosion Prevention and Fire Extinguishing System currently being deployed overcome all the disqualifications of the primitive systems used. Technology ensures to minimize the damage caused in a partially failed transformer by preventing its explosion and consequential damages. The nitrogen based and logical circuit controlled, proactive explosion prevention system contribute significantly to reducing risk and the asset management efforts of the utilities. This system is highly desirable for all critical transformer installations and for all transformers above 10 MVA rating.