Edwards nEXT nEXT85 - Shut down the Pump Manually

WARNING: HOT SURFACE
Risk of burn. Do not touch the ange heater or surrounding surfaces during the
bakeout process as they will be hot.
CAUTION: BAKEOUT PROCESS
Risk of damage to equipment. Pumps with ISO anges are not suitable for bakeout,
only pumps with CF anges must be used. When baking the pump to above 70 °C at
the inlet ange, the pump must be water cooled to prevent damage to the bearing
lubricant.
The manufacturer's ange heater may be used to heat the pump (refer to Accessories on
page 101). Fit the appropriate band around the pump CF inlet ange. When baking the
pump or the system, make sure that the temperature of the inlet ange does not exceed
the values given in Table: General technical data on page 18.
When baking the vacuum system, if the temperature of the system exceeds 200 °C, put a
radiaon shield between the system and the pump. This radiaon shield will reduce the
heat radiated onto the pump rotor.
Typically, a bakeout of four hours is suciently long to remove water condensaon from
the pump. However, the bakeout me will depend on the amount of condensaon in
the pump and the vacuum system, and the ulmate pressure desired.
6.10 Shut down the pump manually
Note:
In an emergency only, open the vent valve quickly to decelerate the pump rotor in the
shortest possible me.
Use this procedure to shut down a basic, manually-controlled pumping system with a
manual vent valve.
1. Set the pump to o, but keep the backing-pump on and backing valve open.
2. When speed has fallen to 50%, open the vent valve.
3.
When the pump reaches standsll, the vent valve and backing valve may be closed
and backing pump set to o.
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B8G000880_D - Operaon