Riser Pipe; If An Adapter Is Required; If Steel Riser Pipe Is Used; If Plastic Or Flexible Riser Pipe Is Used - Grundfos SP Instrucciones De Instalación Y Funcionamiento

6.5 Riser pipe

The riser pipe or hose should be
properly sized and selected on the
Note
basis of estimated flow rates and
friction-loss factors.

6.5.1 If an adapter is required

We recommend you to first install the riser pipe
to the pipe adapter. Then install the riser pipe
with the adapter to the pump discharge port.
Use a back-up wrench when attaching the riser
pipe to the pump. The pump should be gripped
only by the flats on the top of the discharge
chamber. The body of the pump, cable guard or
motor should not be gripped under any
circumstance.
Pipe adapters
or
Fig. 10 Pipe adapters

6.5.2 If steel riser pipe is used

We recommend that steel riser pipes always be
used with the large submersible pumps. Use an
approved pipe thread compound on all joints.
Make sure the joints are adequately tightened in
order to prevent the joints from coming loose
when the motor starts and stops.
When tightened, the first section of the riser
pipe must not come in contact with the check
valve retainer.
After the first section of the riser pipe has been
attached to the pump, clamp the lifting wire to
the pipe. Do not clamp the lifting wire to the
pump.
10
Riser pipe
Pump discharge
When raising the pump and riser pipe section to
upright position, be careful not to place bending
stress on the pump by picking it up by the pump
end only.
Make sure that the power cables are not cut
or damaged in any way when the pump is
being lowered in the well.
Fasten the submersible drop cable to the riser
pipe at frequent intervals to prevent sagging,
looping or possible cable damage. Nylon cable
clips or waterproof tape may be used. The cable
splice should be protected by securing it with
clips or tape just above and below the splice.

6.5.3 If plastic or flexible riser pipe is used

We recommend that you use plastic type riser
pipes only with the smaller domestic
submersible pumps.
When a plastic riser pipe is used,
we recommend that you attach a
Caution
safety cable to the pump to lower
and raise it.
Warning
Important: Plastic and flexible
pipes tend to stretch under load.
This stretching must be taken into
account when securing the cable
to the riser pipe. Leave 3 to
4 inches of slack between clips or
taped points to allow for this
stretching. This tendency for
plastic and flexible pipe to stretch
will also affect the calculation of
Note
the pump installation depth. As a
general rule, you can estimate that
plastic pipe will stretch to
approximately 2 % of its length.
For example, if you installed
200 feet (61 m) of plastic riser pipe,
the pump may actually be down
204 feet (62 m). If the installation
depth is critical, check with the
manufacturer of the pipe to
determine how to compensate for
pipe stretch.
Contact the pipe manufacturer or representative
to ensure that the pipe type and physical
characteristics are suitable for this use.
Use the correct joint compound recommended
by the pipe manufacturer. In addition to making
sure that joints are securely fastened, we
recommend the use of a torque arrester when
using a plastic pipe.