Exhaust Silencers

Naval vessels and power generators are amongst the users of high capacity diesel and gas motors. The unsilenced noise levels produced by these machines are markedly greater than the permissible levels under existing regulations. In addition to the low frequencies middle and high frequency noise is present in the exhaust and it is this that requires especial treatment. An ideal silencer will combine compact proportions with optimum attenuation over the widest possible frequency spectrum with the lowest possible pressure drop. Gas velocities within the silencer should be limited.

Q.E. Exhaust Silencers

QE has built a high reputation for exhaust silencers. The silencers have been installed throughout the world for leading motor suppliers. QE has a range of standard silencers and a design team specialising in producing custom-built units for those applications requiring non-standard solutions. For example: cases with space limitations or very demanding attenuation requirements. QE is unique in combining expertise with innovative solutions for difficult and complex problems. QE silencers are quality products that we guarantee will meet the specified noise levels. The silencers are fabricated in the most economical locations ‚ and are supplied at the keenest prices.

Principle Of Operation

Dependent upon the client’s specifications each silencer design may be based on noise absorption or upon combined resonance/absorption. In either case a spark-arresting version is available.

Absorption silencer:
In this design the gas/vapour flows through a conduit formed from perforated material. The conduit is surrounded by sound absorbent ‚ usually in the form of a blanket of fine threads of an inert mineral. Noise energy entering the blanket is converted to heat energy by continuous friction over the threads.

Combination Resonance and Absorption Silencers:
In those applications having more stringent specifications, especially in the lower frequencies, an alternative design embodies low frequency resonance dampening together with medium and high frequency absorption. The resonance section unites two separate volumetric chambers by one or more throttling tubes so that the gas / vapour expands into the leading volume chamber and is then throttled before expanding into the second of the volume chambers. The proportions of chambers and tubes are selected to impress the maximum effect upon the low frequency pulses from the motor exhaust connection.

Spark Arrestor

There are a number of situations in which a spark-arrestor is required or specified. All QE silencers can be fitted with a spark-arrestor that operates upon the centrifugal principle in which the particles, whether incandescent or not, are separated from the gas-stream by a series of shaped blades and are captured in a particle collector. The collector is designed and located to be easily cleaned. The inclusion of a spark-arrestor ensures a particle-free exhausting gas.

Construction

Required Data