Metal separators of the P-TRON 03 FM type are used for the examination of granulates or ground material in intermittent suction conveyor lines. Versions for horizontal and vertical installation, as well as for high product temperatures after the dryer, are available. The P-TRON 05 GM is available for continuous suction conveyor lines or pressure conveyor lines. Crimping valves and rotary flaps replace the pendulum flap of the P-TRON 03 FM here.