Edwards A373-30-940, Инструкция по эксплуатации

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A373-10-880 Issue R
Page 4 © Edwards Limited 2012. All rights reserved.
Edwards and the Edwards logo are trademarks of Edwards Limited.
Introduction
1.3 Description
The Edwards E2M28 and E2M30 pumps are shown in Figure 1 . Refer to Figure 1 for item numbers in brackets in the
following descriptions.
The E2M28 and E2M30 pumps are two-stage, direct drive, sliding vane pumps. The pump is oil-sealed and designed
for reliable, long-term operation in both laboratory and industrial environments. The pump is a free-standing unit.
The drive is provided through a flexible coupling by a single-phase or three-phase (four pole) motor.
The motors are totally enclosed and are cooled by the motor-cooling fan which directs air along the motor fins.
The single-phase motors have a thermal overload device. When the motor is too hot, the thermal overload device
switches off the pump. The thermal overload device has an automatic reset; when the motor cools down, the device
resets and the motor will restart. The single phase motors have an on/off switch.
An oil pressure system lubricates the pump shaft bearing surfaces and rotor sealing faces. The pump has an oil
distribution valve which prevents discharge of oil to the pump interior (suckback) after the pump stops. The pumping
chambers are air-tight, so this arrangement prevents air suckback unless the gas-ballast valve is open. For protection
in this case, refer to
Section 1.4 .
You can inspect the level and condition of oil in the oil box reservoir through the oil sight-glass (12). An oil filler-plug
(1) is fitted to the top of the oil box. The pump has an oil drain-plug (11) to allow gravity oil drain.
The pump has an inlet-port (6), outlet nozzle (2) and gas-ballast control (3). The pump is mounted on two mild steel
box section skids (10) on rubber pads. Details of suitable vibration isolators and other recommended accessories are
given in
Section 7.5 .
1.4 Gas-ballast
To pump high vapour loads, gas-ballast is delivered into the pump to prevent condensation of the vapour carried by
the pumped gases.
Air (or another gas) can be introduced into the low vacuum stage through the gas-ballast control. The gas-ballast
control is a multi-turn valve which you can adjust, as required, between closed and fully open.