NCCER Industrial Maintenance Mechanic case studies
NCCER Industrial Maintenance Mechanic · Put your knowledge to work in context.
The NCCER Industrial Maintenance Mechanic credential is a knowledge-based assessment for people who keep production machinery running: millwrights, maintenance technicians, multi-craft mechanics, and apprentices moving into plant maintenance roles. It is built around NCCER's Industrial Maintenance Mechanic curriculum, which organizes the trade into a defined set of levels, and the written assessment samples from the same body of knowledge. The NCCER Industrial Maintenance Mechanic case studies are 5 cases and about 4,855 words.
1Sign-Off on a 3,600 rpm Pump/Motor Alignment
A mechanic has finished aligning a 100 hp (75 kW), 3,600 rpm motor to a centrifugal pump using a laser alignment kit and wants your signature so the unit can go back in service. His report, taken with the machine at ambient temperature, shows 0.010 in parallel offset (motor high) and 0.003 in per 10 in of angular misalignment at the coupling.
862 words, about 4 min2Rebuilding a 150 psig Steam Flange and Valve Joint
A 6 in Schedule 40 saturated steam line at 150 psig (about 366 °F) in a food plant has blown a flange gasket twice in two years. The existing gaskets are 1/8 in compressed sheet, and the 6 in gate valve has a worn stem.
916 words, about 5 min3Over-Greased Fan Bearing Running at 195 °F
A forced-draft fan runs at 1,800 rpm on a 22220 spherical roller bearing (100 mm bore, 180 mm OD, 46 mm width) in a pillow block, grease lubricated. The bearing has run at about 195 °F (90 °C) for a month.
1,060 words, about 5 min4Conveyor Motor Tripping on Overload
A 50 hp, 480 V, 3-phase conveyor motor (FLA 65 A) trips its thermal overload after 20 to 40 minutes of running. The overload is a Class 20 set at 65 A.
940 words, about 5 min5Four-Leg Bridle Lift of a Pump Skid
You are asked to approve a lift of an 8,000 lb skid-mounted pump using a four-leg bridle sling with the legs at 45° from horizontal. The four slings in the crib are identical, each with a vertical working load limit of 3,000 lb.
1,077 words, about 5 min