What is Labyrinth Seal?
A labyrinth seal is a type of mechanical seal that provides a tortuous path (knife teeth edge) to help prevent leakage and contamination. Labyrinth seals are the non-contact seal that makes a tougher path for contaminants to enter while operating with little or no friction.
Labyrinth-type seals are used to minimize re-circulation losses within the compressor.
Function of Labyrinth Seals in Turbocharger
- The bearings are separated from the blower and turbine by labyrinth seals.
- These seals are sealed by air supply from the discharge of blower to prevent oil entering the blower and to prevent contamination of the oil by the exhaust gas.
- In case of defective labyrinth seals on blower side, oil is leaked into the air system the cooling surfaces are covered with oil which are insulators and the cooling efficiency will be reduced. Also there will be deposits on the blower and the blower efficiency will be reduced.
- In case of defective labyrinth seals on turbine side, the oil is leaked into the exhaust side and there will be carbon deposits on the nozzle and turbine blades. Reduce blower efficiency and fire in the exhaust piping. It will cause turbocharger surging. Oil will contaminate with exhaust gas.
Material of Labyrinth Seal:
Labyrinth seals are often made of metal, such as aluminum. They can also be made of thermoplastics, which can resist corrosion and rub better.
Other materials used for labyrinth seals include: Bronze, Stainless steel, Plastic.