6.4.2 Magnet inspections
WARNING:
The magnets contained in this unit are extremely powerful. Keep magnetic drive components
and magnetic tools apart from each other by a minimum of 2 m | 6 ft. Serious injury to fingers
and hands will result if you do not follow this precaution.
Driven magnet assembly inspections
Perform these checks on the driven magnet assembly (740A):
•
Check that the assembly is free from bulges.
•
Check that the assembly is free from pits and scratches that exceed 0.127 mm | 0.005 in. deep.
•
Check that the assembly is free from erosion or corrosion that exceeds 0.127 mm | 0.005 in. deep.
•
Check the pump-out vanes for cracks and corrosion.
•
Check that the circulation holes are open.
Drive magnet assembly
The magnets are extremely brittle. It is normal to have chips that amount to 10% of the magnet surface
per MMPA Standard No. 0100-90.
Perform these checks on the drive magnet assembly (740B):
•
Check that the magnets are free of major cracks and extent over 50% of the surface and are free of
imperfections that create loose particles.
•
Replace the magnets if the magnets and drive magnet carrier were exposed to any pumped fluid.
•
Check the drive magnet carrier for cracks and replace if any cracks are found.
•
Check the drive magnet carrier hub OD is free from grooves and scratches that are greater than
0.127 mm | 0.005 in.
•
Check the magnets for proper bonding to the metal carrier.
6.4.3 Bearing-frame inspection
Checklist
Check the bearing frame for these conditions:
•
Visually inspect the bearing frame and frame foot for cracks.
•
Check the inside surfaces of the frame for rust, scale, or debris. Remove all loose and foreign ma-
terial.
•
Make sure that all lubrication passages are clear.
•
Inspect the inboard-bearing bores.
The maximum acceptable bore is 7.203 cm | 2.836 in. for S-group pumps and 9.002 cm | 3.544 in.
for M-group pumps.
•
Inspect the labyrinth seal O-rings for cuts and cracks.
•
Inspect the ball bearings for containment and damage.
•
Make sure the gasket surfaces are clean.
•
Visually inspect the bearing end cover for cracks and pits.
6.4 Pre-assembly inspections
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Model 3296 EZMAG Installation, Operation, and Maintenance Manual
