4-5 PUMP ASSEMBLY SHAFT INSPECT/TEST/REPLACE (CONT).
Grinding operations create airborne dust and particles. Respiratory and
eye protection is required to avoid injury to personnel.
The recorded unbalance can be reduced by grinding material from sides of rotors.
Do not reduce thickness of rotors more than 0.200 inch (5 mm). Before
reassembling the shaft, test the concentricity of the working points.
Test the concentricity as follows:
Place the following components on the shaft: shaft sleeves, impeller wear rings, and spacer.
Place shaft assembly along with components on two pairs of rollers. Revolve the assembly 360° while checking
the concentricity with a dial indicator.
Concentricity on shaft sleeves, impeller wear rings, and spacer shall not exceed 0.003 inch (0.08 mm).
The pump assembly shaft weighs more than 50 lbs. Two personnel are
required to lift the pump shaft to avoid injury.