Nozzle assembly

A nozzle assembly comprising:

• a nozzle housing;
• and
• a nozzle comprising:
• a first nozzle part defining a central nozzle axis (X-X) and having a fluid outlet at a first end and a fluid inlet at an opposed, second end;
• a second nozzle part coaxial with the first nozzle part and surrounding at least a first portion of the first nozzle part;
• and
• a third nozzle part coaxial with the first part, wherein a first portion of the third nozzle part surrounds a first portion of the second nozzle part, and a second portion of the third nozzle part is attached to a second portion of the first nozzle part;
• wherein:
• the first portion of the first nozzle part is interference fitted within the second nozzle part by press fitting or heat shrinking;
• the first portion of the third nozzle part is interference fitted with the first portion of the second nozzle part by press fitting or heat shrinking;
• a second portion of the second nozzle part is received with an interference fit within the housing by press fitting or heat shrinking;
• the first nozzle part and third nozzle part are made of materials having the same first coefficient of thermal expansion (TE1);
• the nozzle housing and the second nozzle part are made of materials having the same second coefficient of thermal expansion (TE2);
• the first coefficient of thermal expansion (TE1) is different from the second coefficient of thermal expansion (TE2);
• and
• the second portion of the third nozzle part is fixedly attached to the second portion of the first nozzle part by a weld;
• wherein the second nozzle part is completely disposed within the housing.