Edwards nEXT730D - Vent Gas Specification and Vent Control Data; Materials Exposed to Gases Pumped

The pump can be used to pump oxygen and water vapour, subject to the following
condions:
▪ O
xygen - The oxygen concentraon must be less than 25% by volume.
4.4 Vent gas specicaon and vent control data
Although the pump may be vented to atmosphere, high relave humidity of the air may
greatly increase the subsequent pump‑down me. To reduce pump‑down mes vent
with dry, clean gases. Refer to Vent opons, vent valve connecon and control on page
76 for a descripon of the vent opons and the vent valve connecon and refer to
Controlled venng opons on page 69 for conguring the venng opons.
Table 7
Vent gas specicaon and vent control
Vent gas specicaon and control Reference data
Vent gas Dry air, nitrogen, argon or other inert
gases
Maximum dew point at atmospheric pres-
sure
-22 °C
Maximum size of parculates 1 µm
Maximum concentraon of oil 0.1 parts per million
Recommended me for rotaonal speed
to reach 50%
> 15 seconds
Maximum allowed rate of pressure rise Refer to gure below
Maximum allowable vent gas supply pres-
sure
1 bar (gauge), 14.5 psig, 2 x 10
5
Pa
Figur
e 7 Maximum allowed rate of pressure rise during venng: pr
essure against me
1
10
100
1000
0 50 100 150 200 250 300
mbar
s
BC-0036-A
4.5 Materials exposed to gases pumped
The follo
wing materials and component types are exposed to the gases pumped:
▪ Steel and aluminium alloys
▪ Fluoroelastomer and O‑rings
▪ Hydrocarbon lubricant
▪ CFP
▪ Rare earth magnets
▪ Silicon nitride
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B8J200880_D - Technical data