Flowserve TB-MAG INNOMAG - Manual (Page 19)

INNOMAG® TB- MAG™ ASME and ISO SEALLESS ENGLISH 26999988 06-14
Page 19 of 44
4.5 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.
4.5.1 Suction and discharge piping
Never use the pump as a support
for 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.
The following is the recommended procedure for
attaching piping to the TB-
MAG™ pump (see section
6.5 for torque values)

Check the surface of both flanges (pump/pipe) to
ensure they are clean, flat, and without defects

Lubricate the fasteners

Hand tighten all of the fasteners in a crisscross
pattern

The fasteners should be torqued in increments –
based a crisscross pattern

See torque chart in Section 6.5
o The first increment should be 75% of full torque
o The second increment should be at the full
torque
o Verify that the torque value of the 1 st
fastener is
still at the full torque value. Re-torque all
fasteners after 24 hours or after the first
thermal cycle.

Re-torque all fasteners at least annually
4.5.2 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 4-5 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 4-6 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 vapour
or suspended solids, concentric reducers are
preferable to eccentric reducers.
Figure 4-5
Figure 4-6
Avoid the use of throttling valves and strainers in the
suction line. 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 Centrifugal Pump IOM Section of the
H.I. Standards for additional recommendations on
suction piping. (See section 10.)
Refer to section 3.4 for performance and operating
limits.
4.5.3 Discharge piping
Install a valve in the discharge line. This valve is
required for regulating flow and/or to isolate the
pump for inspection and maintenance.
When fluid velocity in the pipe is
high, for example, 3 m/s (10 ft/sec) or higher, a
rapidly closing discharge valve can cause a
damaging pressure surge. A dampening
arrangement should be provided in the piping.
4.5.4 Allowable Nozzle Loads
Maximum Forces and moments allowed on pump
flanges vary based on the pump size. When these
forces and moments are minimized, there is a
corresponding reduction in misalignment, hot