In-Line Silencers

In many industries miles of pipes that transport gas represent the major source of noise. The noise is generated by control valves, compressors or fans located inside of the pipe. To reduce pipe-radiated noise efficiently, an inline silencer must be inserted into the pipe. This inline silencer must be able to block the transmission of both the gas-borne noise propagating inside the pipe and the structure-borne noise propagating as vibration in the pipe wall.

After intensive investigations and testing, we have developed inline silencers that fulfill both these requirements. Instead of the usual sound absorbing material of mineral wool or fiberglass, these new silencers utilize a woven fabric as the sound absorbing material.

The woven material, which is not directly exposed to the flow, allows much higher velocities in the silencer passage than the traditional silencers with fibrous fill and can withstand much higher mechanical loads. It maintains the high initial acoustic performance for a much longer time period than the traditional inline silencer. In cases of large inside diameter and high attenuation requirements in the high frequency range, our silencer is fitted with a sound absorbing center baffle.

These silencers have been deployed successfully in many different noise control applications. especially cost efficient system noise control solutions can be achieved by mounting a multistage throttling unit in front of the silencer. After our customers supply us with operational data and gas parameters, we custom design our Inline Silencers utilizing our proprietary computer programs. Field testing of numerous completed installations has validated this computerized design procedure.

Advantages of our Inline Silencers:

• Wide application range in pipe engineering and related fields
• Use of woven fabric as a sound absorbing material allows easy cleaning
• High passage velocity
• Available in all practical diameters and for all practical pressure ranges
• Small, compact construction and high acoustic performance
• High structure-borne attenuation along the silencer walls
• High cost effective system noise control solution by mounting multistage throttling devices in front of the silencer.

Input Information for Inquiry:

• Description of the sound source and the pipe
• Gas, design density, isentropic exponent [kg/m³]
• Operating pressure and operating temperature in front and behind the sound source [bar, Deg. C]
• Length of pipe between the sound source and silencer [m]
• If available, A-weighted sound power level in the pipe behind the sound source [dB (A)]
• Required insertion loss [dB] or maximum permitted A-weighted sound power level behind the silencer [dB (A)]