Note:
Remove the four rubber feet from the four tapped fixing holes before you mount the
base of the pump.
Obey the requirements that follows to make sure that the pump stay secured if the
pump seize:
Support must withstand a destructive
torque of:
6 KNm
Fixing screws:
8 quantity of M8 to ISO898-1 strength
class 12.9 (nominal tensile strength 1200
MPa)
Screw engagement length:
6 mm minimum
Fastening torque:
15 Nm (1.53 kgf.m)
Use this method for installation if the pump supports the weight of the vacuum system.
Make sure that the weight of the vacuum system is not more than 20 kg.
4.3.5 Backing port connection
WARNING: PUMP OVER
‑
PRESSURE
Risk of damage to equipment. To prevent over-pressure in the pump, do not limit the
exhaust line when you vent from a positive pressure gas supply.
CAUTION: BEARING LIFE
Risk of damage to equipment. Do not use the pump with a backing pressure less than
5 x 10
-4
mbar (5 x 10
-2
Pa). Lower backing pressures increases the evaporation rate of
the lubrication oil and can decrease the life of the bearings.
Note:
Make sure that the ducting is done at the backing line if oil mist or hazardous substances
are available.
Use applicable vacuum tubing and connectors to connect the NW flange of the backing
port to the backing pump. If necessary, use flexible pipe or bellows to decrease the
transmission of vibration from the backing pump to the pump.
We recommend you to use our EM, RV or XDS Scroll backing pump. The recommended
size of backing pump is given in
Table: nEXT pumps technical data on page 17
. A larger or
smaller backing pump can be used, depending upon the application it is intended for.
The pumps are applicable to use with diaphragm backing pumps but the effect of higher
backing pressure on the pump's performance and cooling requirements must be noted.
Refer to
Table: nEXT pumps technical data on page 17
.
Page 36
B85200880_D - Installation
