A needle bearing from a filling and seating machine for milk cartons became unusable due to corrosion and fracture of a ring after only four weeks of operation of the machine in a Finnish milk packing plant. These bearings were subject to corrosion by water condensates in this type of environment because of constant temperature changes, and they normally are replaced after eight months. The bearings were lubricated by a molybdenum sulfide paste. Judging by their structure the needles probably consisted of ball bearing steel. They showed corroded initial cracks of the pitting type, i.e., shear-fatigue fractures due to...