Vent Gas Specification And Vent Control Data; Materials Exposed To Gases Pumped; Figure 7 Maximum Allowed Rate Of Pressure Rise During Venting: Pressure Against Time - Edwards nEXT730D Instruction Manual

The pump can be used to pump oxygen and water vapour, subject to the following
conditions:
▪ Oxygen - The oxygen concentration must be less than 25% by volume.

4.4 Vent gas specification and vent control data

Although the pump may be vented to atmosphere, high relative humidity of the air may
greatly increase the subsequent pump‑down time. To reduce pump‑down times vent
with dry, clean gases. Refer to
76 for a description of the vent options and the vent valve connection and refer to
Controlled venting options
Table 7 Vent gas specification and vent control
Vent gas specification and control
Vent gas
Maximum dew point at atmospheric pres-
sure
Maximum size of particulates
Maximum concentration of oil
Recommended time for rotational speed
to reach 50%
Maximum allowed rate of pressure rise
Maximum allowable vent gas supply pres-
sure

Figure 7 Maximum allowed rate of pressure rise during venting: pressure against time

1000
100
10
1
0

4.5 Materials exposed to gases pumped

The following 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
B8J200880_D
300812671_002_C3
B8J200880_D - Technical data
Vent options, vent valve connection and control
on page 69 for configuring the venting options.
50 100 150
Page 30
Reference data
Dry air, nitrogen, argon or other inert
gases
-22 °C
1 µm
0.1 parts per million
> 15 seconds
Refer to figure below
1 bar (gauge), 14.5 psig, 2 x 10
300 s
200 250
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5
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