13 free movement, 14 timing gear replacement – Flowserve MP1 Sier-Bath User Manual
Page 33
MP1 USER INSTRUCTIONS ENGLISH 26999958
– 10-12
Page 33 of 48
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flat face joint between it and the NDE bearing
housing [3459.1]. Use the NDE fasteners [6572.3]
and plain grease to keep this gasket in place while
mounting the gear housing to the already installed
NDE bearing housing.
n) Mount gear housing [1600.1] to the NDE bearing
housing [3459.1]. Tighten all NDE fasteners
[6572.3]
o) Install the timing gear bearings [3012.2] outer
races, cages and rolling elements assemblies only
into the gear housing [1600.1]; the inner races of
these bearings must have been mounted already
on the shafts.
p) Slightly and evenly heat the thrust [ball] bearings
[3013.1] inner races up to facilitate to mount them
onto the shafts and into the gear housing [1600.1].
q) Install the thrust bearing retainer plates [8448.1]
and lock them up using the fasteners [6579.2].
r) Install the NDE cap [1610.1]. If new bearings are
being installed, check that the insertion length of
the cap is greater than the recess in the gear
housing bore by approximately 0.001 in. to 0.002
in., by measuring the length of the protrusion of
the NDE cap [1610.1] from the face of closure to
the gear housing [1600.1], and the recess from the
face of the gear housing [1600.1] and the visible
face of the outer race of the thrust bearings
[3013.1]. Any larger and tightening of the rear cap
capscrews will distort the cap. Any shorter and
contact will not be made with the bearing by the
cap.
s) Mount a new flange gasket [4510.1] on the DE
bearing housing [3459.1].
t) Mount DE cover [3530.1] with lip seal [2450.1] in
place, on the DE bearing housing [3459.1].
u) Re-verify that all dowel pins are in right place and
re-verify and re-tighten all bolts and screws to their
required torques.
6.13 Free movement
If the pump does not turn freely after reassembly, the
following procedure should be observed.
a) The mechanical seal setting tabs may cause the
pump to be difficult to turn. However, this should
not prevent rotation of the rotating element.
b) Confirm the seal plates and bearing brackets are
match marked to each other. It is important to
install them in the same location as they were
originally installed. These parts are machined as
matched sets and ALWAYS use dowel pins to
locate the two parts together.
c) Verify the faces of the seal plates, bearing
brackets and timing gear housing are flat and
parallel. Make sure to clean up any burrs that may
have occurred during the repair process.
d) Occasionally there may be more than one set of
dowel pin holes due to a prior repair. Make sure to
use the current dowel pin holes to assure the
proper screw/bore alignment.
e) Make sure the proper spacers are installed on the
drive and driven shafts between the timing gear
super nuts and the timing gear bearings. It is
critical to ensure they are sitting flat against the
shoulder of the respective shaft.
f) Remove the NDE cap(s) and confirm the axial
clearance between the cap and the outer race of
the bearings is 0.0005 in. to 0.0010 in. if there is a
hard shim installed or the wavy springs are
installed and provide tension.
g) Continue with step
“l” from section 6.12 Re-
assembly.
If pump does not turn freely after executing Steps a
through f, it is due to incorrectly dimensioned parts or a
timing problem. Contact the nearest Flowserve Pumps
Service Representative for assistance. Also see
section 6.14 Timing gear replacement of this manual
provide guidance in verifying the timing of the rotating
element.
6.14 Timing gear replacement
If new timing gears are to be installed on the rotating
elements, they must be timed before key slotting. The
reason for this is that the timing gear radial position on
the shaft determines the critical axial clearance
between the pumping screws. In the average screw
pump, the change in clearance between the meshing
screws is about 0.001 in. for each 0.004 in. distance in
circumference at the pitch diameter of the timing gear.
Since the normal axial clearance of meshing screws
varies with the size of pump and viscosity of the fluid
that the pump was designed for, very accurate key
slotting is essential for proper operation.
To replace the timing gears, the following procedure
should be used.
a) For optimum results it is highly recommended that
a set of timing stands as shown in Figure 10 and
Table 10 be manufactured.
b) Mount the shafts with the screws intermeshed onto
the timing stands resting the shafts on the bearing
diameters. The bearings are not mounted on the
shafts at this time.
c) Install the driven shaft timing gear key [6700.1].
d) Slide the driven shaft timing gear [2300.2] partially
onto its respective shaft diameter, engaging the
key.
e) Slide the drive shaft timing gear [2300.1] partially
onto its respective shaft diameter with the existing