Pulsafeeder Isochem GM12 Series, Installation, Operation, & Maintenance Instruction

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9. Do not spring piping, either suction or
discharge when mating up to the pump. Use
supports or hangers at intervals as required.
When necessary, provide for thermal
expansion and contraction so no strain is
placed upon the pump.
10. Check all bolts and nuts for tightness. Correct
any conditions which could cause destructive
vibration or leakage.
11. Where required, provide proper system for
containment can recirculation.
12. If start-up screens are used, be sure they do
not clog and starve suction. Start-up screens
should be removed prior to placing system into
regular operation.
13. If flexible suction lines are used, be sure their
selection and installation will prevent wall
collapse and thus a starved suction condition.
14. When taking suction from a tank or vessel,
avoid entry of sludge, solids, etc. into suction
line by placing suction line inlet above
maximum expected level of solids.
15. Discharge line should be fitted with properly
sized pressure relief valve to protect both pump
and discharge system. Pressure relief valve
outlet should be piped back to the supply tank.
16. When a by-pass system is used to control flow
from the pump, the bypassed fluid should be
piped back to the suction vessel to prevent
heat build-up due to recirculation. If it is
absolutely necessary to pipe by-pass back to
the pump suction line, the point of entry should
be at least
1
0 pipe diameters away from the
suction inlet. Provision for cooling should be
made in the event of excessive heat buildup
through fluid recirculation.
17. Where pumped fluids may solidify, crystallize,
precipitate etc., provision should be made to
thoroughly flush pump and piping prior to
periods of shutdown. Pay particular attention to
proper flushing and draining of the magnetic
coupling area because this area will not self
drain. There is a drain plug in the front housing
for access to this area.
OPERATION
1. Prior to operation, make sure all suction piping is
air tight and clean. Check that electrical service to
motor agrees with name plate ratings. Jog to
check rotation and for signs of binding. To check
rotation, observe the motor fan. Rewire motor if
necessary.
2.
Isochem Gear pumps are designed to handle
clear fluids at viscosities up to
500,000
SSU
(100,000
CPS).

No gear pump should be run dry. Damage
to wear surfaces will result.

Pumping fluids containing abrasives
should be avoided as accelerated pump
wear will result.
3.
It is recommended that pumps with metallic drive
and idler gears not be run with fluids having a
viscosity less than
500
SSU (
1 00
CPS) or at
speeds greater than
1450
RPM.
4. The pump will self-prime if fluid is supplied at the
pump inlet. If foot valves are used, the valve
should be of the flapper type and sized to
minimize friction loss.
5. If the pump is to operate near the boiling point of
the fluid being pumped, a recirculation loop can be
set up between the drain connection in the front
housing and the suction with provisions for flow
control in the recirculation loop.
6. Do not operate the pump against a closed
discharge. Doing so will cause the magnetic drive
to decouple. High temperatures will then be
created which can cause the fluid to boil or
damage the magnet assemblies. If decoupling
occurs, stop the motor and restart after the
obstruction has been cleared. As a safety
precaution a pressure relief valve by-pass system
is highly recommended. Ideally the pressure
relief valve is set for a low pressure for start-up.
7. Start pump with discharge and suction valves
open and check for proper operation. Excessive
noise or vibration is an indication of harmful
cavitation which is due to insufficient NPSH (Net
Positive Suction Head).