VARISCO JB Serie Instrucciones Para Su Utilizacion Y Mantenimiento página 21

ISTRUCTIONS FOR THE USE AND MAINTENANCE -
The pump does not deliver liquid
13.2
12 The pump is not primed
see the points listed under 13.1
13 The head required by the system is greater than the rated head of the pump
revise the system design or re-select the pump
14 Excessive friction losses in the suction line
revise the distribution of elbows, valves, restrictions etc.; if necessary increase the diameter of the pipework
15 The impeller is clogged by foreign objects
disassemble the casing and remove the foreign objects
16 The suction or discharge lines are obstructed or clogged
locate the obstructed or clogged area and clean.
13.3 The pump does not have sufficient capacity
17 Air leaks in the suction line
check that the couplings are airtight and inspect the suction line
18 The impeller and/or wear plate are worn
they should be replaced by disassembling the pump as described in paragraphs 12.2 and 12.3.
19 The diameter of the suction line is too small
replace the suction line. Check the other possible causes in paragraph 13.2.
13.4 The pump does not provide enough pressure
20 The viscosity of the liquid is higher than expected
contact the manufacturers after measuring the viscosity; for centrifugal pumps this should not exceed 50 cSt.
Check other possible causes: see point 5 of paragraph 13.1 and paragraph 13.2.
13.5 The pump absorbs too much power
21 The rotation speed is too high
check the correct rotation speed
22 The pump operates under conditions which are different for those specified
check the operating conditions of the pump and compare them to those on the pump nameplate
23 The density of the liquid is higher than specified
measure the density (or specific gravity) of the liquid and compare it to the agreed figure
24 Incorrect alignment of the unit
check that the unit is correctly aligned as described in paragraph 10
25 Friction inside the pump between the rotating and non rotating components
remove the pump casing as described in paragraph 12.2 and check if there are signs of rubbing on the surfaces
26 Foreign bodies trapped in the impeller
remove the pump casing as described in paragraph 12.2 and remove the foreign bodies.
13.6 The pump vibrates and is noisy
27 The pump is operating at a too low capacity
check the settings of the valves in the system and the readings on the pressure and vacuum gauges
28 The pump or the pipework are not well fixed
check that the pipework is correctly clamped
29 The pump cavitates
see paragraph 13.2. Check ofther possible causes in paragraph 13.1
30 The impeller is clogged by foreign objects
disassemble the casing (see par. 12.2) and remove the foreign objects.
13.7 The pump jams
31 Mechanical breakdown
check the shaft, flexible coupling, engine, pulleys and belts, gear boxes etc. for breakages.
32 Foreign bodies jammed inside the pump
inspect the inside of the pump casing through the impeller inspection cover or remove the pump casing (see paragraph 12.2).
13.8 The bearings have a short lifetime
33 Lack of lubrication
lubricate the bearings as described in paragraph 12.7
34 Foreign bodies in the bearings
change the bearings (see par. 12.8)
35 The bearings are rusted
change the bearings (see par. 12.8).
13.9 The mechanical seal leaks
36 1 - 2 type seal
this type of seal is suitable for pumping dirty liquids or liquids containing abrasive particles or petroleum products at temperatures up
to 110°C; grease every 500 hours through the grease nipple until grease comes out behind the seal. If well lubricated, this seal can
run dry for 2 minutes. If the seal leaks during operation, it must be replaced (see paragraph 12.5).
JB / JD
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