Flowserve Mark 3 Sealed Metallic Durco - Manual (Page 24)

MARK 3 USER INSTRUCTIONS ENGLISH 71569102 01-13
Page 24 of 72 flowserve.com
4.5.3 C-Flange motor alignment
C-flange motor adapters provide a means of
obtaining pump to motor alignment. A C-flange type
motor is mounted on the pump bearing housing with
the use of an intermediate adapter. Alignment is
achieved through the use of machined locating and
piloting surfaces on the bearing housing and adapter.
Care should be taken to insure these surfaces are
kept free from handling damage defects or dirt which
will affect alignment.
Alignment between the pump shaft and motor shaft is
built-in by the precise machining of the parts that
position these shafts. Parallel alignment of .007 and
angular alignment of .002 can be expected. Should a
more refined alignment be desired, an optional
alignment feature is available. See section 4.5.4
4.5.4 C-Plus alignment feature
If the C-PLUS alignment feature is desired the spacer
ring must be installed before the motor is assembled.
The drawing below shows the components of the C-
PLUS feature.
The motor mounting screws must be snug but not
tight when attempting to adjust motor location.
Depending on the size of motor it may be necessary
to check the alignment with the motor fasteners tight.
Corrections may be made until 0.002" TIR (or the
desired) alignment is achieved. The adjusters,
adjuster jam nuts and the motor fasteners should all
be tightened.
The indicator kit should be removed, the coupling and
coupling guard properly installed
4.6 Piping
Protective covers are fitted to both the
suction and discharge flanges of the casing and must
be removed prior to connecting the pump to any pipes.
4.6.1 Suction and discharge piping
All piping must be independently supported, accurately
aligned and preferably connected to the pump by a
short length of flexible piping. The pump should not
have to support the weight of the pipe or compensate
for misalignment. It should be possible to install suction
and discharge bolts through mating flanges without
pulling or prying either of the flanges. All piping must be
tight. Pumps may air-bind if air is allowed to leak into
the piping. If the pump flange(s) have tapped holes,
select flange fasteners with thread engagement at least
equal to the fastener diameter but that do not bottom
out in the tapped holes before the joint is tight.
4.6.2 Suction piping
To avoid NPSH and suction problems, suction piping
must be at least as large as the pump suction
connection. Never use pipe or fittings on the suction
that are smaller in diameter than the pump suction size.
Figure 4-12 illustrates the ideal piping configuration with
a minimum of 10 pipe diameters between the source
and the pump suction. In most cases, horizontal
reducers should be eccentric and mounted with the flat
side up as shown in figure 4-13 with a maximum of one
pipe size reduction. Never mount eccentric reducers
with the flat side down. Horizontally mounted concentric
reducers should not be used if there is any possibility of
entrained air in the process fluid. Vertically mounted
concentric reducers are acceptable. In applications
where the fluid is completely de-aerated and free of any
vapor or suspended solids, concentric reducers are
preferable to eccentric reducers.
Figure 4-12 Figure 4-13
Start up strainers must be removed shortly before start
up. When the pump is installed below the source of
supply, a valve should be installed in the suction line to
isolate the pump and permit pump inspection and
maintenance. However, never place a valve directly on
the suction nozzle of the pump.
Refer to the Durco Pump Engineering Manual and
the Centrifugal Pump IOM Section of the Hydraulic
Institute Standards for additional recommendations
on suction piping. (See section 10.)