Oil Cooling System is used for removing the heat due to energy loss from the transformer oil cooling circuits, the choke and the inverter. Oil Cooling System is used in WAG9, WAP7 & WAP5 class of locomotives manufactured by Chittaranjan Locomotive Works, India. Two such units are used per locomotive. The Oil Cooling Blower’s are used for cooling the oil of transformer and three auxiliary converters that flows through the heat exchanger assemblies.

The oil of the transformer flows through the radiator 1 that is mounted under the floor of the locomotive. The oil carrying the heat from auxiliary converter flows through the radiator 2 that is place right above the radiator 1 of transformer under the locomotive floor.

The Oil Cooling Blower is mounted right above both the radiators 1 & 2 inside the locomotive such that the fresh cooling air is sucked from the top of the locomotive by Oil Cooling Blower through the duct connected to the top of the Oil Cooling Blower box cools the radiators at the other end of the box.

The Oil Cooling Blower box is connected to the roof opening of the locomotive through a duct and cyclonic filter at the roof. This cyclonic filter is responsible for filtering the incoming cool air that is sucked by the Oil Cooling Blower and this cool air takes off the heat from the radiator fins through convection method and escapes out from the bottom of the locomotive.