The pressure drop that you choose will depend upon what the silencer is connected to and how sensitive that item is. For something like a control valve it is possible to calculate the change in capacity due to back pressure imposed by a silencer and ensure that there is no effect on operation, whilst with a compressor, jet pump or steam ejector any back pressure, or pressure loss, can adversely affect the performance of the unit.
Pressure drop is the difference between the incoming pressure and the outgoing pressure
Pressure drops across in-line silencers can be very low, but they can never be zero. In the best cases they will approach values similar to that which would be obtained by substituting plain pipe for the silencer.
You can have as much pressure drop as you want, however you need to check that the capacity of the system to achieve the required flow is not adversely impacted by a high pressure drop across the silencer
Noise can bypass an in-line silencer by travelling along the walls of the silencer casing and is particularly a problem at low frequencies. In most cases this is not a problem because the noise generated by most devices is too high in frequency to cause a problem. However, just because most devices don't cause a problem does not mean this issue can be ignored as compressors and jet pumps, can, depending on their operating conditions, generate significant low frequency noise.
The internal packing arrangement in Flo-Dyne silencers has been proven over the last 35 year to be robust in nature and resilient against packing loss, due to the protection and retention measures that are employed to keep all fibrous packing inside the silencer.
The need for acoustic cladding will depend on the noise levels that are being provided by the silencer. Most installations will not require acoustic insulation at all, however where we are working to deliver noise levels as low as 65 to 75 dB(A) acoustic cladding at the inlet end of the silencer may be necessary.
