Perforated end pipe of silencer unit

An end pipe for a silencer unit of an automotive vehicle for suppressing noise originating from an exhaust gas flow from the vehicle engine, comprising:

• at least one perforated section having a predetermined extension in the longitudinal direction of the end pipe and being positioned downstream of a point along the end pipe where substantially no turbulent exhaust flow through the end pipe can be expected, said perforated section having a length amounting to a portion of the total length of said end pipe and corresponding to a value at which predetermined limit values regarding suppression at relatively low frequencies and relatively high frequencies of said noise are satisfied.

A method for providing a silencer unit of a vehicle adapted for suppressing unwanted noise originating from an exhaust gas flow from a vehicle engine, said method comprising:

• providing an end pipe at one end of said silencer unit through which said exhaust gas flow is conveyed to the surroundings, said end pipe further provided with at least one perforated section wherein said perforated section has a predetermined extension in a longitudinal direction of said end pipe and positioning said perforated section downstream of a point along the end pipe where there is substantially no turbulence in the exhaust flow, and
• configuring said perforated section to have a length amounting to a portion of the total length of said end pipe to cause noise originating from an exhaust gas flow from a vehicle engine passing through said perforated section to correspond to predetermined limit values regarding suppression at relatively low frequencies and relatively high frequencies.