Abstract: A vortex separator, operating as a dust filter system for air intake machines, such as gas turbines and other internal combustion engines, includes dust filters having first and second casings arranged coaxially with helical bladed inserts mounted within the upstream ends of the casings, and an air outlet connector extending coaxially of the downstream end of the second casing. The downstream end of the first casing surrounds and forms an annular space with the upstream end of the following casing, and the downstream end of such following casing surrounds and forms an annular space with the upstream end of the air outlet connector.