Helium turbomachinery operating experience from gas turbine power plants and test facilities

► Test data compiled from helium turbomachines operated over the last five decades. ► Operating history of Oberhausen helium gas turbine and HHV test facility valuable. ► Positive results, extended high temperature operation, rotor cooling system, seals. ► Problems, high rotor vibration, blade and bearing failure, power output deficiency. ► Data bases from operated machines will aid design of future helium turbomachinery.