Patent ID: 7980063

Claim:
A dosing device for administering a reducing agent into an exhaust chamber of an internal combustion engine, the dosing device being adapted for mounting within a port of said exhaust chamber and comprising a nozzle body and an insulating jacket; the insulating jacket at least partially surrounding the nozzle body and defining a compartment between the insulating jacket and the nozzle body; wherein the compartment is substantially evacuated and the dosing device is configured such that, when the dosing device is mounted within the port of the exhaust chamber, the nozzle body is separated from the port by the substantially evacuated compartment; wherein the insulating jacket is mounted to the nozzle body at one or more mounting points and the insulating jacket is adapted to engage with the port at an engagement point that is remote from the or each mounting point wherein the insulating jacket is adapted to form an interference fit within the port at the engagement point.