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m-530dun-gb-01
9.2
Dos and don'ts
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Do not build a pump into a tight location without adequate airflow around the pump.
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Do keep delivery and suction tubes as short and direct as possible - though ideally not shorter than one
metre - and follow the straightest route. Use bends of large radius: at least four times the tubing
diameter. Ensure that connecting pipework and fittings are suitably rated to handle the predicted pipeline
pressure. Avoid pipe reducers and lengths of smaller bore tubing than the pumphead section, particularly
in pipelines on the suction side. Any valves in the pipeline must not restrict the flow. Any valves in the flow
line must be open when the pump is running.
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Do ensure that on longer tube runs at least one metre of smooth bore, flexible tubing is connected to the
inlet and discharge port of the pumphead to help to minimise impulse losses and pulsation in the pipeline.
This is especially important with viscous fluids and when connecting to rigid pipework.
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Do use suction and delivery pipes equal to or larger than the tubing diameter bore. When pumping
viscous fluids use pipe runs with a bore several times larger than the pump tube.
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Do site the pump at or just below the level of the fluid to be pumped if possible. This will ensure flooded
suction and maximum pumping efficiency.
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Do run at slow speed when pumping viscous fluids. Flooded suction will enhance pumping performance,
particularly for materials of a viscous nature.
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Do recalibrate after changing tubing, fluid or any connecting pipework. It is also recommended that the
pump is recalibrated periodically to maintain accuracy.
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Do not pump any chemical not compatible with the tube or pumphead.
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Do not run the pump with no tube or element fitted to the pumphead.
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Do not strap the control and mains cable together.
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Do ensure if your product has an N module, that the module is fitted with the seals intact and properly
located. Ensure that the holes for the cable glands are properly sealed to maintain the IP/NEMA rating.
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If your pump is a PROFIBUS variant do ensure that it is installed in accordance with PROFIBUS
installation guidelines.
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Do not allow tight bends in any PROFIBUS signal cable.
Tube selection: The chemical compatibility guide published on the Watson Marlow website is for guidance. If
in any doubt about the compatibility of a tube material and the duty fluid, request a Watson- Marlow tube
sample card for immersion trials.
When using Marprene or Bioprene continuous tubing, do re-tension the tube after the first 30 minutes of
running.
