Motor History --Select-- Existing motor in service long time New replacement motor recently purchased,installed New replacement motor,stored for a long period Old existing motor,removed,reconditioned,re-installed Replacement, used, reconditioned motor from storage Replacement used motor from stores not reconditioned New motor in new application or installation Reason for Removal from Service --Select-- Routine maintenance interval Shutdown process ie machinery out for service anyway Operation problem - was not working as it should Problem with operating conditions ie flood, power problems Diagnostic evaluation-not sure what problem is Mechanical Diagnosis Bearing failed due to circulating currents Bearing failure Bearing inner race welded to the shaft Bearing is brunelled Bearing outer race welded in housing Bearing overlubricated Bearing spun on the shaft Bearing underlubricated Bent foot Broken foot Channeling of rotating bearing elements Copper or aluminum spatter Core iron failed core loss test Cracked or open rotor bar(s) End shield cracked End shield hit windings End shield pinched leads Fan cracked Fan loose Fan missing or broken fins Fan retainer clip groove worn Fan retainer clip missing Feet not flat (in the same plane) Foot cracked Internal fan hit windings Irons got hot Irons misaligned Irons uneven Leads blown in terminal box Liquid migrated into shaft or opposite end bearing Loose coils Loose sticks Loose wedges Motor overspeed Oil boiled out of shaft end grease Retainer bolts loosened Retainer scrubbed on the shaft Rotor moved on the shaft Rotor scrubbed on the irons, damaged laminations Rotor spun on the shaft Shaft discolored Shaft is bent at the shoulder Shaft is broken at the shoulder Shaft is peened over Shaft scrubbed Shaft slinger or seal failed Shaft stub worn Shorting ring is open Slot insulation failed Snakes, mice, bees Stator cracked Stator irons delaminated Stator irons moved Water line in stator or end shields Winding blown at the corner Winding blown in slot Worn bearing housing(s) Worn shaft end or opposite shaft end bearing journal Mechanical Repair Assemble, test, paint Balanced rotor Bored fan hub Brush plating repair Chiseled and burned off Coil cut-off and burn off Cold stripped Converted from F1 to F2 (or vice versa) Converted to open bearings Converted to sealed bearings Converted to shielded bearings Laminations repaired Magnaflux rotor irons Masked stator Paint Replace shaft Rewound and pour varnished Rewound two dips and bakes Shaft seal(s) replaced Shaft slinger replaced Shaft weld repair Siliconed terminal box Sleeve repair Spray weld repair Stator rabbet(s) repaired Step key fabricate Stripped and data collected Electrical Diagnosis Air gap densities high Back iron densities high Blown connections Blown leads at connections Growled the rotor Hipot test failed Leads grounded - pinched in the end shield Leads grounded in the terminal box Megger windings One coil in one group is burned out One phase is burned Phase to phase short PI test failed Post cleaning test failed Shorted connections Start around the clock Surge test failed Tie cord is brittle or crispy Tie cord is broken Tooth densities high Winding blown at the corner Winding blown in the slot Winding chaffed against end shield Winding coils reversed Winding data is incorrect Winding is grounded Winding overvoltage failure Winding single phased Winding turn to turn short Winding unevenly overheated Wire behind the paper Electrical Repair Class F epoxy Class F insulating spray Connect, form and tie Continuity phase method winding Converted concentric to lap winding Converted consequent pole to lap winding DEVCON 5 minute epoxy windings Form wedges Lead sleeving Leads or connections were tied Leads replaced Motor was connected for 3 leads Motor was connected for 9 leads Pull up leads, reconnect Reconnect for different voltage Rewound class H Siliconed leads Tied down leads Tied on overloads VPI windings Weave winding Winding cleaned and baked Winding cleaned and re-insulated Winding cleaned and varnished Winding re-designed Wound for a different frequency Wound for a different speed Wound for different (higher/lower) voltage
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