Disassembly, Inspection & Reassembly
216 Series Twin-Screw Pump -
Installation, Operation, and Maintenance Manual
65
Screw shaft replacement guidelines
Screw shaft measurement check
Check the mechanical seal, bearing and gear wheel fits of the screw shafts (100) using
outside precision micrometers with a measurement sensitivity of 0,0025mm (0.0001in). If any
are outside the tolerances shown in the fits and tolerances table, then replace the screw
shaft.
Screw shaft inspection
NOTICE:
Do not use the screw shaft centers for the runout check as they may have been damaged
during the removal of the bearings or gears.
Screw shaft inspection
Screw shaft runout check
Using precision “V” blocks support the screw shaft at the two bearing locations shown.
Rotate the shaft slowly by gripping the coupling location. Be sure not to apply excessive
force which might deflect the shaft and can result in a false reading. Use a rigidly supported
precision dial with a measurement sensitivity of 0.0025mm (0.0001in). The measured runout
of the screw shaft should not exceed 0.05mm (0.002in) at any location.
