Page 16
•
MN01047
Issue/Rev. 0.0 (10/18)
Section IV – Assembly (continued)
Figure 43 – Tighten Cover Bolts
Cover Bolt
Tighten the Shaft Fixture Bolt (2" – 50 in/lbs, 3" – 90 in lbs)
in order to seat the Shaft within the Housing. Check
clearance between the bottom of the Blades and the
Housing Shelf once Shaft Fixture Bolt and Washers
have been installed (Figure 40). Clearance should be
.002"/.003". Adjust, if needed, by adding or removing
Shims.
Figure 40 – Blade to Inside Surface
Check the Blade Tip to Housing clearance at the outlet,
inlet, and middle portion of the Measuring Chamber
(Figure 41).
Figure 41 – Blade Tip to Housing Clearance (at the
Measuring Chamber)
It may be required to insert shims behind the Block and
Measuring C hamber in order to obtain required clearances
(Figure 42). The required Shim thickness can be calculated
by taking the Rotor to Block clearance and subtracting
the Blade Bearing to Cam clearance and recommended
clearance from the Rotor to the Block. Be sure to align
the holes in the Shim(s) with the holes in the Block and
Housing. In order to install shims the Spider assembly
will need to be removed. Shims should be flush with or
below the Block or Measuring Chamber.
Figure 42 – Shims
Once required clearances have been achieved, the cover
can be installed. Prior to installing the cover, inspect
the Cover O-ring and if damaged, replace it. Reinstall
the O-ring (lubricate the O-ring with a thin coating of
Molykote 55 O-Ring Grease). Install the Cover and torque
the Cover Bolts with a torque wrench (Figure 43). Use a
cross-hole tightening pattern when tightening the bolts.
Note:
When installing the Housing Cover, take caution when aligning
it with the Rotor Magnetic Coupling. It should not be forced, but slip
over the magnet. Misalignment could damage or chip the coupling.
Cover Bolt Torque Specifications:
2" Torque Value: 45 ft/lb (61 N
•
m)
3" Torque Value: 160 ft/lb (217 N
•
m)
