steam air and other gases are vented to atmosphere at high
velocities noise is created. Typically the higher the velocity
the louder the noise level. Penn makes two models of exhaust
silencers to reduce noise levels.
The SP Silencer
The SP Exhaust Silencer is a single
pass silencer designed to give maximum attenuation of both
low and high frequency noise for air, steam, or gas exhausting
The SP-S Silencer
The SP-S Exhaust Silencer is an economical
approach to silencing where the noise level reduction does
not have to be as great as the SP model. The SP-S Silencer
has the same physical configurations as the SP Silencer except
that it is two-thirds the length of an SP Silencer.
gas enters the inlet of the silencer where the flow
is disbursed through the inlet diffuser tube into hundreds
of small jet flows. This provides for quite flow of
the gas into the silencer and the first stage silencing
chamber. The diffuser also directs the flow toward the
outer walls of the silencer body. The gas then repeats
the same process contracting and expanding into the
second stage chamber. The second chamber reacts with
the noise the same way as the first chamber dissipating
and absorbing the noise that is left over. The second
chamber also has an important function as a reflow area.
It allows for an even flow of gas to the outlet. This
assures the quiet release of gases to the atmosphere
trough an adequately sized outlet.
silencer reduces noise differently. The larger the size,
the higher the reduction. These reductions range from
24 to 46dB (A) depending on the model. The following
page gives these combined reductions as well as sizing
information, and suggested specificaions, and dimensions.
SP and SP-S Exhaust Silencers have the same quality
of workmanship that has gone into all Penn Products
for so many years and is guaranteed for a year against
defects in materials or workmanship.