Coolant expansion tanks - simple application, varied tasks

Pressurised coolant expansion tanks must meet demanding requirements including:

  • Resistance to mechanical load
  • Fluctuations in temperature
  • Pressure and chemical composition of the fluid
  • Dimensional stability
  • Corrosion resistance
  • Leak-proof construction and flexibility 


MANN+HUMMEL provides customised coolant expansion tanks for industrial machinery such as construction equipment and agricultural machinery. We develop optimum installation geometry for the tank and the design of individual components including hoses, level sensors and pressure caps.
MANN+HUMMEL moulded tanks not only prevent air bubbles from forming in the coolant expansion tank, but also eliminate air bubbles in the entire cooling system.
This is achieved by creating an optimised flow of fluid through the tank. In the development phase, we test prototypes on modern test rigs under realistic conditions. MANN+HUMMEL validates the coolant expansion tanks in-house,
ensuring that every tank leaving the factory meets customer expectations.