go to the Transformers product page John asked on Apr 8th, 2014 in Transformers

How does oil circulates on the transformer on transformer without pumps?

Transformers team, Transformers team

ABB's answer

There are two possibilities to drive an oil flow in transformers:

  1. by separate pumps as mentioned by you (forced convection)
  2. by the density difference between hot- and cold regions in the oil (natural convection)

Generally, in transformers both methods are applied, usually a forced oil convection with separate pumps is only used for special designs in the large power range. The natural convection is sufficient strong to transport the heat to the heat exchangers in most transformers.

The natural convection itself is driven exactly in the same way, as it is well known e.g. from ocean currents. Heated fluid has a lower density than cold fluid, and this causes a driving force in the warm fluid which is directed upwards in the gravitational field. After reaching the heat exchanger, the fluid cools down, its density rises, and it falls back downwards for becoming heated again.

Like this answer 3 people liked it already!


Submit comment cancel

Area expert

  • Giuseppe Petrelli

    Giuseppe Petrelli

    Global Marketing and Sales Manager


Contact ABB

If you want to purchase a product, need any pricing information or need help or support from ABB, please contact your local partner.

Haven't found what you've been looking for?

or Ask a question or Contact ABB

ABB's website uses cookies. By staying here you are agreeing to our use of cookies. Learn more