High Frequency Fatigue Failure In Silencer/Pulsation Dampers For Oil Free Screw Compressors.
Abstract
Oil-free screw (OFS) compressors are capable of producing
high-pressure pulsations in the discharge gas stream, over a
frequency range of 200 to 3000 Hz. The fundamental pressure
pulsation is due to the opening cycle of the compressor lobes at the
discharge porting and is referred to as the pocket passing frequency
(PPF). Fatigue failures have been observed in discharge
silencers/pulsation dampers as well as downstream piping
components in oil-free screw compressor service where the
frequencies were greater than 1000 Hz. A careful review of the
pulsation damper design has shown that attenuation effectiveness
is limited to frequencies less than 1000 Hz. The principal purpose
of the pulsation damper is to reduce the line pressure pulsations in
order to lessen the chances of downstream piping failures. The
pulsation damper does very little to attenuate high frequency noise
levels that are transmitted to the area surrounding the compressor.
The principal purpose of this paper is to document failures of
silencer/pulsation dampers in OFS compressor service and provide
a root cause analysis of these failure modes. Pulsation dampers are
not used at the inlet flange in many applications, due to the lowpressure
pulsation in the inlet plenum of the compressor. It is not
the intent of this paper to present any theoretical background in the
design of acoustic dampers, but to provide an overview of the
acoustic phenomenon and how it is used in screw compressor
applications. The end result of this work will be to provide
practical guidelines for specifying silencer/pulsation dampers for
OFS compressor applications.
Description
LecturePg. 141-146
Subject
TurbomachinesCollections
Citation
Lovelady, Jeff; Bielskus, Pete A. (1999). High Frequency Fatigue Failure In Silencer/Pulsation Dampers For Oil Free Screw Compressors.. Texas A&M University. Turbomachinery Laboratories. Available electronically from https : / /hdl .handle .net /1969 .1 /163393.