Edwards nRVi, Instruction Manual

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WARNING:
Risk of injury and damage to equipment. Instructions must be obeyed and note taken
of precautions to ensure that pumped gases do not enter their flammable ranges.
Switch off the purge flow at the end of the process only after any remaining flammable
gases or vapours have been purged from the pump and exhaust pipeline.
If liquids that produce flammable vapours could be present in the pump foreline, then
the inert gas purge to the pump should be left on all the time this liquid is present.
Flammable liquids could be present in the foreline as a result of condensation or may be
carried over from the process.
When calculating the flow rate of inert gas required for dilution, consider the maximum
flow rate for the flammable gases/vapours that could occur. For example, if a mass flow
controller is used to supply flammable gases to the process, assume a flow rate for
flammable gases that could arise if the mass flow controller is fully open.
Continually measure the inert gas purge flow rate: if the flow rate falls below that
required, stop the flow of flammable gases or vapours into the pump.
Note:
Refer to the Vacuum Pump and Vacuum System Safety manual (publication number
P40040100), supplied with the pump.
4.2.2 Flammable and pyrophoric materials
When flammable or pyrophoric materials are present within the equipment, take the
following precautions.
WARNING:
Risk of injury and damage to equipment. Instructions must be obeyed and note taken
of precautions to ensure that pumped gases do not enter their flammable ranges.
▪ Do not allow air to enter the equipment.
▪ Ensure the system is leak tight.
▪ Use an inert gas purge (for example, a nitrogen purge) to dilute any flammable
gases or vapours entering the pump inlet, and/or use an inert gas purge to reduce
the concentration of flammable gases or vapours in the pump and in the exhaust
pipeline to less than one quarter of the gases published Lower Explosive Limits
(LEL).
▪ Use an inert gas purge into the pump gas ballast connection to prevent the
condensation of flammable vapours within the pump mechanism and exhaust
pipeline.
4.3 Unpack and inspect
The pump is supplied on a wooden pallet with a cardboard covering and requires lifting
equipment.
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A65901880_D - Installation