Self-cleaning tramp metal separation device for pneumatic conveying lines

A tramp metal separation device for removing contaminants from a stream of raw materials that is being conveyed by a pneumatic conveying line having an upstream portion and a downstream portion, the tramp metal separation device comprising:

• a first housing having an inlet and an outlet, wherein the inlet is connectable to the upstream portion of the pneumatic conveying line and the outlet is connectable to the downstream portion of the pneumatic conveying line;
• a face plate;
• a plurality of elongate magnet members that each extend from a first end to a second end, wherein the first end of each elongate magnet member is connected to the face plate;
• a wiper plate having a plurality of bores that each have a respective one of the elongate magnet members extending therethrough;
• at least one actuator operatively connected to the face plate, for moving the face plate and the elongate magnet members in unison between an extended position and a retracted position;
• and
• a support structure operatively connected to the wiper plate for supporting the wiper plate for movement between an operating position and a cleaning position, the support structure having a biasing element for biasing the wiper plate toward the face plate and a mechanical stop for limiting travel of the wiper plate away from the first housing, wherein movement of the face plate from the extended position toward the retracted position causes movement of the wiper plate under influence of the biasing element, and the face plate continues moving toward the retracted position after movement of the wiper plate is limited by the mechanical stop at the cleaning position such that the elongate magnet members are cleaned as they slide through the bores of the wiper plate while the face plate continues moving toward the retracted position.

A tramp metal separation device for removing contaminants from a stream of raw materials that is being conveyed by a pneumatic conveying line having an upstream portion and a downstream portion, the tramp metal separation device comprising:

• a first housing having an inlet and an outlet, wherein the inlet is connectable to the upstream portion of the pneumatic conveying line and the outlet is connectable to the downstream portion of the pneumatic conveying line;
• a face plate;
• a plurality of elongate magnet members that each extend from a first end to a second end, wherein the first end of each elongate magnet member is connected to the face plate;
• a wiper plate having a plurality of bores that each have a respective one of the elongate magnet members extending therethrough;
• at least one actuator operatively connected to the face plate, for moving the face plate and the elongate magnet members in unison between an extended position and a retracted position;
• a support structure operatively connected to the wiper plate for supporting the wiper plate for movement with respect to the first housing between an operating position and a cleaning position, wherein the wiper plate is disposed within the first housing, is located adjacent to the face plate, and is located adjacent to the first ends of the elongate magnet members when the wiper plate is in the operating position and the face plate is in the extended position, and the wiper plate is disposed outside of the first housing, is spaced apart from the face plate, and is located adjacent to the second ends of the elongate magnet members when the wiper plate is in the cleaning position and the face plate is in the retracted position, wherein the support structure includes a biasing element that biases the wiper plate toward the cleaning position and a mechanical stop that stops movement of the wiper plate when the wiper plate reaches the cleaning position;
• and
• a controller operatively connected to the at least one actuator for causing the face plate to move from the extended position toward the retracted position such that the wiper plate moves in unison with the face plate until the wiper plate reaches the cleaning position and the face plate continues moving with respect to the wiper plate after the wiper plate reaches the cleaning position such that the elongate magnet members are cleaned as they slide through the bores of the wiper plate while the face plate moves toward the retracted position.