Instruction manual

Oct 04 Issue H
GV Dry Vacuum Pumps
PAGE
27
27
MAINTENANCE
5.3 Check the gearbox oil-level and fill
the gearbox with oil (if necessary)
Note: If you need to pour oil into the gearbox
frequently, or if there is a sudden loss of a large
amount of oil, the pump may be faulty: shut
down the pump and contact your supplier or
BOC Edwards.
Figure 1 shows the locations of the two oil-level
sight-glasses on the pump. Refer to Figure 10 and
check that the pump gearbox oil-level is at the MAX
mark on the bezel of the oil-level sight-glass (10): see
Figure 1, detail C. If the oil-level is below the MAX
mark:
1. Remove the oil filler-plug (12) and bonded seal
(13) from the oil-filler port (1), fit a suitable
funnel to the oil-filler port, then pour oil
through the funnel into the pump gearbox until
the oil-level is at the MAX mark on the bezel of
the oil-level sight-glass (see Figure 1, detail C).
2. If you overfill the gearbox:
• Place a suitable container under the oil drain-
plug (3);
• Unscrew and remove the drain-plug (3) and
bonded seal (4) and allow oil to drain from the
gearbox;
• When the oil level reaches the MAX mark on
the sight-glass (see Figure 1, detail C), refit
and tighten the oil drain-plug (3) and bonded
seal (4);
• Continue at Step 1 again, to check that the oil-
level is now correct.
WARNING
The pressure in the gearbox will be
equal to the pressure of your shaft-
seals purge gas supply. Loosen the oil
filler-plug and wait for two or three
seconds for the pressure in the
gearbox to equalise before you
remove the oil filler-plug or oil drain
plug. If you do not, oil may be ejected
under pressure from the gearbox.
3. Refit the oil filler-plug (12) and bonded seal (13)
to the oil-filler port (1).
5.4 Inspect the gas ballast system
Use the following procedure to inspect the gas-
ballast system.
Note that if you have not connected a nitrogen gas-
ballast supply, the gas-ballast air filter element must
be replaced every three years as part of the pump
overhaul (see Section 5.15). However, you may
need to replace the air filter element more
frequently if you use the GV pump in an
environment where there are excessive air-borne
particulates; refer to Table 16 for the Item Number
for a new air filter element.
1. If you have connected a nitrogen gas-ballast
supply, continue at Step 6, otherwise continue
at Step 2 to inspect the air filter element.
2. Refer to Figure 8. Turn the top-cap (1)
clockwise (when viewed from the top-cap end
of the gas-ballast air filter) to release it from the
filter body (4), then remove the top-cap.
3. Inspect the filter element (3); if there are
excessive deposits lodged in the air filter,
continue at Step 4, otherwise continue at Step 5.
4. Remove and dispose of the used filter element
(3), and fit the new filter element (3) into the
filter body (4).
5. Refit the top-cap (1) to the filter body (4) and
turn it anticlockwise until it clicks, to secure it
to the filter body: ensure that the inlet (2) on
the top-cap does not point upwards, otherwise
debris, dust or liquids may enter the filter body.
6. Refer to Figure 8 (page 28). Inspect all of the
clamps (4, 6, 9) in the gas-ballast system and
check that they are secure: tighten any loose
connections.