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9.3 Pump mounting
Warning
CR, CRI, CRN pumps are shipped with covered
suction and discharge ports. Remove the covers
before the pipes are connected to the pump.
9.3.1 Recommended installation torques
Recommended
Pump type
foundation torque
[ft-lbs]
CR, CRI, CRN 1s/1/3/5
30
CR, CRI, CRN 10/15
37
9.4 Suction pipe
The suction pipe should be adequately sized and run as straight
and short as possible to keep friction losses to a minimum
(minimum of four pipe diameters straight run prior to the suction
flange). Avoid using unnecessary fittings, valves or accessory
items. Use butterfly or gate valves in the suction line only when it
is necessary to isolate a pump because of a flooded suction
condition. This would occur if the water source is above the
pump. See fig. 4 and fig. 5. Flush piping prior to pump installation
to remove loose debris.
Butterfly
valve
Check
valve
Expansion joints
Flooded suction
Fig. 4
Butterfly
Check
valve
valve
Suction lift*
Fig. 5
* The suction pipe should have a fitting on it for priming.
Recommended
flange torque
[Nm]
[ft-lbs]
[Nm]
40
37-44
50-60
50
44-52
60-70
Reservoir
Butterfly
valve
Strainer
Eccentric
reducer
Suction
pipe
Reservoir
Foot valve
9.4.1 Suction pipe sizes
The following recommended suction pipe sizes are the smallest
sizes which should be used with any specific CR pump type.
The suction pipe size should be verified with each installation to
ensure good pipe practices are being observed and excess
friction losses are not encountered.
High temperatures may require larger diameter pipes to reduce
friction and improve NPHSA.
Pump type
[inch] [mm]
CR, CRI, CRN 1s, 1, 3
1
CR, CRI, CRN 5
1.25
CR, CRI, CRN 10, 15
2
9.5 Discharge pipe
We suggest to install a check valve and an isolating valve in the
discharge pipe.
Pipe, valves and fittings should be at least the same diameter as
the discharge pipe or sized in accordance with good piping
practices to reduce excessive liquid velocities and friction losses
in pipes.
The pressure rating of pipes, valves and fittings
Caution
must be equal to or greater than the maximum
system pressure.
Before installing the pump, pressure check the discharge piping
to at least the maximum pressure the pump is capable of
generating or as required by codes or local regulations.
Whenever possible, avoid high pressure loss fittings, such as
elbows or branch tees directly on either side of the pump.
The piping should be adequately supported to reduce thermal
and mechanical stresses on the pump.
According to good installation practices, clean the system
thoroughly and flush it of all foreign materials and sediment prior
to pump installation. Furthermore, never install the pump at the
lowest point of the system due to the natural accumulation of dirt
and sediment. If there is excessive sediment or suspended
particles, we recommend that a strainer or filter is used.
Grundfos recommends that pressure gauges are installed on
suction and discharge flanges or in pipes to monitor pump and
system performance.
Min. suction pipe size
Nominal diameter acc.
25
to ANSI schedule 40
Nominal diameter acc.
32
to ANSI schedule 40
Nominal diameter acc.
50
to ANSI schedule 40
11
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