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For your nearest Roots office contact information, please consult the last page of this document.
GAS Blowers
WHISPAIR
™
Gas Blower
WHISPAIR Gas Blower units are the same general design as
the standard WHISPAIR model except that (4) mechanical
seals are used in place of the (4) inboard lip seals. The seal
chambers are piped to plugged connections. These should
be opened periodically to confirm that there is no build-up of
oil due to leakage by the mechanical seal. Special traps may
be required for vacuum operation. These units are intended
for use with all gases which are compatible with cast iron,
ductile iron, viton o-rings, 300 & 400 series stainless steel
and carbon components of the mechanical seals. If there are
any questions as to suitability of materials, consult the Roots
sales office.
Precaution: WHISPAIR Gas Blower
The mechanical seals may leak some amount of the process
gas to the atmosphere through the gear/box end cover
breather caps. If this leakage is undesirable, for toxic/haz-
ardous gases, provide inert purge gas in the vent chamber
between the mechanical seals and the piston ring seals, refer
to Figure 1a. The purge gas pressure in the vent chamber
should be maintained at about 1 psi over the discharge pres-
sure.
The plugged drain connections are provided to allow periodic
draining of any fluid which might accumulate in the seal
chamber. This can be a combination of lubricating oils, liq-
uids entrained in the process gas, or condensables from the
process gas.
Care must be used when opening the vent
drain plugs as some gas will also escape if it is a pressure
system. For system under vacuum the air will leak in. Never
vent explosive or toxic gases in an unsafe manner. Care
must be used when opening oil fill and oil drain plugs. The
gas leakage past mechanical seal could accumulate in the
gear box and drive end cover oil sump areas and leak out to
the atmosphere.
If there is any question regarding applica-
tion or operation of this gas pump consult the Roots sales
office.
Conversely, if the system is under vacuum, there will be leak-
age of atmospheric air into the system through the breather
and the lube chamber, and by the mechanical seals or from
vent drain when plug is open. This gas will contain oil vapor.
If the process gas is non-toxic/non-hazardous and the leaked
gas needs to be piped away, refer to Figure 1a for piping
arrangement. The piping arrangement should not cause back
pressure in excess of 10” water column.
Figure 1a
