6 fastener torques, 7 setting impeller clearance, 8 disassembly – Flowserve CPXS User Manual
Page 26

CPXS, CPXNS and CPXPS USER INSTRUCTIONS ENGLISH 71569250 07-11
Page 26 of 48
flowserve.com
More specialized equipment:
•
Bearing pullers
•
Bearing induction heater
•
Dial test indicator
•
C-spanner (wrench) - for removing shaft nut.
(If difficulties in sourcing are encountered,
consult Flowserve.) Order as follows:
Part no. N.919GZ172 for Model 80 units.
Part no. N.919GZ173 for Model 100 and 150
units.
6.6 Fastener torques
Screw size
Torque Nm (lbf•ft)
M 6
M 8
M 10
M 12
M 16
M 20
11 (8)
16 (12)
25 (18)
35 (26)
80 (59)
130 (96)
Model 80
70 (53)
Model 100
100 (74)
Inner rotor locknut
[6580]
Model 150
150 (110)
Non-metallic gaskets incur creep
relaxation - before commissioning the pump check
and retighten fasteners to tightening torques stated.
Torque up bolts crosswise on all bolting
patterns, DO NOT torque in a circle
6.7 Setting impeller clearance
This procedure may be required after the pump has
been dismantled or a different clearance is
required.
a) Position the pump casing [1100] with the
suction flange facing down on the bench.
b) Install the casing gasket [4590.1] followed by
the inner rotor/casing cover assembly.
c) Tighten the casing bolts [6570.2].
d) Locate a dial indicator on top of the pump shaft
[2100.1] to enable its vertical movement to be
recorded.
e) Loosen inner rotor locknut [6580] and record
shaft drop when the impeller touches the pump
casing. This is a measure of the current front
clearance. Check 3 times at 120 degree
intervals and record the smallest value.
f) Record this reading on line 1 below. Subtract
gasket compression factor - 0.15 mm (0.006
in.) and record on line 3 below:
Line
Detail
mm (in.)
1
Shaft drop
2
Gasket compression factor
0.15 (0.006)
3
Line (1 - 2)
4
Design front clearance
5
Shim adjustment required (3 - 4)
g) Subtract the design front clearance from the
total shaft drop recorded in line 3 to arrive at
the shim adjustment.
IF POSITIVE - ADD SHIMS
IF NEGATIVE - SUBTRACT SHIMS
Design front clearances are:
Impeller diameters up to 210 mm inclusive 0.3 mm (0.012 in.)
Impeller diameters 211 mm to 254 mm
0.4 mm (0.016 in.)
h) Re-install the inner rotor and tighten up the
locknut in accordance with torques shown in
section 6.6.
i)
Check axial float is between 0.5 and 1.5 mm
(0.02 and 0.06 in.).
6.8 Disassembly
Refer to Safety section before dismantling the
pump.
Before dismantling the pump for
overhaul, ensure genuine Flowserve replacement
parts are available.
Refer to sectional drawings for part numbers and
identification. See section 8, Parts lists and drawings.
Refer to section 6.5, Tools required for instruments
needed during dismantling and assembly
procedures. These tools are not supplied with the
pump but can be ordered from Flowserve if
required.
The "back pullout" design of these units enables
the pump casing [1100] to be left in line. The outer
assembly or inner assembly can be removed
without disturbing the pump end thus allowing
examination of the outer rotor and bearing housing
ball bearings.