Noise From Installation - Danfoss APP series User Manual

Instruction
5.

Noise from installation

Cause
5.1 Inlet/outlet connections (hoses/pipes)
5.2 Length/dimension of inlet/outlet line
5.3 Hose stiffness
5.4 Hoses/pipes mounted directly on frame
5.5 Vibration damper under the electric motor 5.5.1 Mount a vibration damper below the
48
Trouble shooting guide for APP pumps
Remedy
5.1.1 Use flexible hoses at inlet/outlet connec-
tions. Danfoss A/S can provide flexible
hoses. Please contact Danfoss sales office
for further information.
5.1.2 Mount the connections to the frame by a
vibration damper mounting plate.
5.2.1 Increase pipe diameter and/or reduce the
number of bends.
5.3.1 Use amore flexible hose. Danfoss A/S can
provide flexible hoses. Please contact
Danfoss sales office for further informa-
tion.
5.4.1 Mount the connections to the frame by a
vibration damper mounting plate.
motor/pump.
180R9265 / IOM APP 16-22 Appendices - v02 / 01.2013
Comments
Non-flexible connectionsmounted directly on
the frame will cause even small pressure
pulsations from pump and create vibrations in
the system/plant.
Too small pipes or too many bends may create
too fast flow/turbulence through the pipes and
thus increase the noise level.
Too stiff hoses cannot damp the small pressure
pulsations from the pump, and subsequently
vibrations occur in the system/plant.
If the hoses are mounted directly on the frame,
the small pressure pulsations from the pump
can be transferred to the frame and the rest of
the system/plant.
When no damper is installed below the electric
motor, vibrations from the motor and pump
may be transferred to the frame/r est of the
system/plant.