Relief valves for high temperature fluid

A relief valve comprising:

• a valve body defining a fluid passageway between an inlet and an outlet, the valve body including:
• a first body portion having a first side with a first opening and a second side with a second opening, the second opening forming the outlet of the fluid passageway, the first body portion constructed of a first material;
• and
• a second body portion coupled to the first side of the first body portion, the second body portion disposed outside of the first body portion, the second body portion having a channel aligned with the first opening, the second body portion forming the inlet of the fluid passageway, the second body portion constructed of a second material having a higher temperature rating than the first material;
• a nozzle disposed in the fluid passageway, the nozzle having a first end forming a seat and a second end opposite the first end, the first end disposed in the first body portion, an outer surface of the nozzle threadably coupled to an inner surface of the first body portion, the second end of the nozzle disposed in the second body portion and welded to an inner surface of the second body portion;
• and
• a flow control member moveable relative to the seat between a closed position and an open position.