Viking Pump TSM341.1: SG Mag Drive Series - Manual (Page 17)

SECTION TSM 341.1 ISSUE J PAGE 17 OF 19
4. The pump is dry and should be primed.
Fluttery, jumping or erratic reading would indicate:
1. The liquid is vaporizing.
2. The liquid is coming to the pump in slugs, possibly an
air leak or insufficient liquid above the end of the suction
pipe.
3. Vibrating from cavitation, misalignment, or damaged
parts.
4. Decoupling of magnetic coupling, possibly due to
pressure spikes.
Pressure Gauge - Discharge Port
High reading would indicate:
1. High viscosity and small diameter and/or lengthy
discharge line.
2. Strainer or filter plugged.
3. Pressure relief valve set too high.
4. Valve in the discharge line partially closed.
5. Line is partially plugged from build up on inside of pump,
solidified product or foreign object.
6. Liquid in pipe not up to temperature.
Low reading would indicate:
1. Pressure relief valve set too low.
2. Pressure relief valve poppet not seating properly.
3. Pump mounting capscrews not torqued to specifications
(SG-804 Series 12-15 ft.-lbs).
4. Pump assembly bolts not torqued into specifications
(SG-807 Series 50-55 ft.-lbs).
5. Bypass around pump is partially open.
6. Too much extra clearance.
7. Pump damaged or worn.
8. Magnetic coupling is decoupling.
Fluttery, jumping or erratic reading would indicate:
1. Cavitation.
2. Liquid is coming to the pump in slugs.
3. An air leak in the suction line.
4. Vibrating from misalignment or mechanical problems.
Pump does not pump:
1. Lost its prime from an air leak or low level in tank.
2. Suction lift is too high.
3. Rotating in the wrong direction.
4. Motor does not come up to speed.
5. Suction and discharge valves are not open.
6. Strainer is clogged.
7. Bypass valve open, pressure relief valve set too low or
pressure relief valve poppet is stuck open.
8. Pump is worn out.
9. Any changes in liquid, system or operation that would
help explain the trouble, e.g. new liquid, additional lines
or process changes.
10. Temperature changes either in the liquid or the
environment.
11. Magnetic coupling is decoupling. Change in application
(temperature, pressure, viscosity, etc.) may require
additional torque beyond coupling capabilities.
Pump starts, then looses its prime:
1. Supply tank is empty.
2. Liquid is vaporizng in the suction line.
3. Air leak or air pockets in the suction line.
4. Pump is worn out.
Pump is noisy:
1. The pump is being starved (heavy liquid cannot get
to pump fast enough). Increase the suction pump size
or reduce the length. If pump is above the liquid, raise
the liquid level to approach the liquid level of the pump.
If the liquid level is already above pump, increase the
head of liquid.
2. Pump is cavitating (liquid vaporizing in suction line).
Increase the suction pipe size or reduce the length. If
pump is above liquid, raise the liquid level to approach
the level of the pump. If the liquid level is already above
pump, increase the head of liquid.
3. Check alignment.
4. Anchor the base or piping to eliminate vibration.
Pump not delivering up to capacity:
1. Starving or cavitating - increase the suction pipe size or
reduce the length.
2. Strainer is partially clogged.
3. An air leak somewhere in the suction line.
4. The pump is running too slow. Is the motor the correct
speed and wired up correctly?
5. The pressure relief valve is set too low, stuck open or
has a damaged poppet seat.
6. A bypass line around pump partially opened.
7. The pump worn out.
Pump takes too much power (stalls motor):
1. Liquid is more viscous than unit is sized to handle.
2. System pressure relief valve set too high.
3. Coupling is mis-aligned.
4. Bushings froze up or liquid set up in the coupling.
DO’S AND DON’TS
Do’s and Don’ts for installation, operation and maintenance
of Viking pumps to assure safe, long, trouble free operation.
Installation:
1. DO install pump as close to supply tank as possible.
2. DO leave working space around the pumping unit.
3. DO use large diameter pipe with short and straight runs.
4. DO install a strainer in suction line.
5. DO a double check of alignment after unit is mounted
and piping is hooked up.