Crews were called to the plant at 4100 Millennium Blvd. SE, just before 10 p.m.
When firefighters arrived smoke was coming from the roof, Assistant Chief Paul Harbaugh said. The production line was in the south side of the building.
Personnel had been evacuated from the building and the sprinkler system had been triggered, he said. The fire was contained to the line and did not impact the structure.
Shearers maintenance personnel ventilated the building.
Perry Fire Department provided a medical unit.