Fristam Pumpen FDS 1 Series, Original Operating Manual Assembly Instructions

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11.3 Fault table
Issue Possible cause Remedy
Pump does not pump or pumps irregularly Pump interior not filled completely with fluid;
discharge valve closed Fill the pump interior with fluid;
Open the discharge valve
Blocked or clogged suction line Open or clean the suction line
Pump with geodetic suction head
1
: Liquid
drops during standstill and housing runs idle
Install foot valve in the suction line
Suction line leaky; seal on the pump cover is leaky
and draws air Seal the suction line; replace the cover seal
Air pocket in the suction line Lay the suction line with continuously rising ele-
vation and with few diversions
Pump is blocked; debris in pump Clean the inside of the pump; visual inspection;
consult
Fristam
Viscosity of the pumped medium is too high;
not able to flow, too viscous Consult Fristam
Coupling penetrated due to previous
overloading Consult Fristam
Delivery rate too great Oversized pump Consult Fristam
Speed too high Decrease speed
Delivery rate too low, pump head too low Pump selected is too small; motor speed too low
due to incorrect frequency Consult Fristam ;
Connect in accordance with the motor nameplate
Suction line leaky and draws air Fix leaks
Viscosity of the pumped medium is too high (too
viscous); possible conversion to integrate a heating system;
consult
Fristam
Wear on the displacement device; gap dimension
too large Repair/replacement
Incorrect direction of rotation Carry out pipe and electrical connections properly
Metallic noise Debris inside the pump Dismantle, assess, repair as needed
Mechanical start-up of the feed screws;
Feed screw nut is loose Dismantle, rework,
Correct slackness setting, tighten with tightening
torque, replace
Excessive wear on bearings and gears wheels due
to overloading or insufficient lubrication Dismantle, assess, repair

Regular maintenance; lubricant service
Speed too high Use motor with frequency converter;
Consult
Fristam
Pump running dry; shaft seal running dry Supply pumped medium immediately; supply
barrier water immediately
Flow noise Operation in load range Adjust operating point of the configuration
Flow losses in the suction line too great Increase the size of nominal widths,
Rule out throttling
Cavitation Check condition for NPSH calculation; see
Chapter 6.6 “Install pipelines”, Page 11 ;
Consult Fristam
Vibrations Dead weight and hydraulic forces of the pipelines
are putting strain on the pump. Support the pipelines in such a way that the
pump is not subjected to strain; integrate vibra-
tion dampers as needed; make sure pressure
shocks do not reach the pump
Incorrect alignment of coupling Align the coupling in accordance with the cou-
pling manufacturer’s specifications
Excessive heating of the pump
shaft bearing and drive gear Bearing damage Dismantle, replace bearing
Lack of lubricant Replace lubricant;

Regular maintenance, see Table 5 on page 18 , or
replenish
Incorrect alignment of coupling Align the coupling in accordance with the cou-
pling manufacturer’s specifications
Table 6 Fault table