Inspection Detail

Inspection: 1253287.015 - Weir Slurry Group, Inc.

Inspection Information - Office: Madison Area Office

Investigation Summary

At 10:30 a.m. on July 31, 2017, Employee #1 was operating the Mazak Megaturn Nexus 900M CNC vertical turning lathe, Serial No. 263752, at a company that manufactures pumping equipment for mining industries. Employee #1 was machining an upper bearing housing, Part No. 574598-016-51, which was secured to a fixture using threaded push rods, and the fixture was then secured in the CNC spindle jaws. The spindle jaws, fixture, and upper bearing housing were rotating around fixed tooling that was machining an inner surface of the bearing housing. The rotational speed was approximately 400 to 500 RPM. The employee had not installed holding clamps in addition to using the push rods to secure the bearing housing to the fixture, in accordance with the employers documented procedure that he had been trained on. The upper bearing housing became dislodged from the fixture during the turning cycle, and the fixture then became dislodged from the spindle jaws of the CNC machine. The bearing housing came to rest within the CNC enclosure, but the fixture was ejected from the CNC machine after it struck the sliding door/machine guard, causing the lower track mechanism to dislodge. This action allowed the fixture to be ejected out of the CNC machine, where it struck the legs of Employee #1, resulting in soft tissue damage to the right leg and bone contusions. The employee also sustained a concussion when he struck his head on a pallet, as he fell to the floor. Employee #1 was working alone at the time of this incident, but other employees were in the immediate area. The employee was hospitalized for two or more days due to his injuries.

Keywords: Concussion, Ejected, Fall, Head, Lathe, Leg, Spindle, Struck By