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a vent line to allow gas to escape to the atmosphere.
Review all federal, local and fi re codes to ensure
that venting is a safe option. For instance, venting
nitrogen to the local atmosphere can be dangerous
in small enclosed areas as asphyxiation can occur.
Contact local OSHA representatives for assistance in
determining safety requirements for different gases.
Purging - It may be necessary to purge the packings
with an inert gas like nitrogen. Purging requires a loop,
whereby the purge gas, at pressure, can be routed to
a safe location for disposal of the mix of purge and
process gases.
Padding - A pad gas like nitrogen can be used to
pressurize the packings at a pressure higher than
the suction pressure of the booster compressor. Any
leakage of the pad gas will enter the process gas
stream contaminating the gas stream. However, the
pad gas will prevent the process gas from leaking to
atmosphere. This is often done in situations where
very tight gas control is required. As the pad gas may
leak to local atmosphere, precautions must be taken
to ensure it will not endanger personnel, property, or
equipment. Contact local OSHA representatives for
assistance in determining safety requirements for
different gases.
‘B’ SERIES BOOSTERS - The ‘B’ series booster
compressor is designed to compress air or
nonhazardous/non-contaminating gases, as follows
(see Figure 16):
B21 - Two pairs of tangent-tangent segmented
packings per rod, set for suction pressures above
ambient and below 100 psig.
B31 - Three pairs of tangent-tangent segmented
packings per rod, for inlet pressures of 100 psig to
165 psig.
B22 - Two pairs of tangent-tangent segmented
packings per rod, set for suction pressures at or below
ambient.
B32 - Three pairs of tangent-tangent segmented
packings per rod, set for suction pressures at or below
ambient, with tighter leakage control than the B22
arrangement.
Additional ‘B’ style packing arrangements can be
engineered for specialty applications. If your ‘B’ style
compressor does not match to the four listed above,
contact the factory for assistance.
The ‘B’ series of gas packings does not allow for a
vent or purge option. Therefore, there is no protection
if gas escapes past the packings -the gas releases
into the open crosshead piece, and will escape to the
surrounding atmosphere. This may be acceptable for
gases other than air, depending upon the location of the
compressor (indoor/outdoor), how well the compressor
is ventilated with fresh air, and the gas itself. Contact
your local OSHA representative and fi re marshall for
assistance in determining safety requirements for all
gases.
B21 Series:
No. of Packings per Rod: 2
Pressure side: Top
Vents: Plugged
Maximum Inlet Pressure: 99 psig
Minimum Inlet Pressure: 1 psig
Figure 16: Gas Packing Arrangements for ‘B’ Series Air Boosters and Gas Compressors
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