Desuperheater nozzle

A nozzle assembly for a desuperheating device for spraying cooling water into a flow of superheated steam passing through a steam pipe at an elevated pressure, the nozzle assembly comprising:

• a cylindrically configured nozzle housing having an open forward end, an open aft end and an interior annular housing shoulder concentrically disposed therein, the nozzle housing securing the nozzle assembly to the steam pipe;
• a cylindrically configured nozzle barrel concentrically disposed within and abutting the housing shoulder of the nozzle housing, the nozzle barrel having an open annular barrel chamber disposed proximate the forward end of the nozzle housing, and no more than three flow passages of arcuate cross-section extending axially through the nozzle barrel in equidistantly spaced relation to each other, each of the flow passages fluidly communicating with the barrel chamber for providing a flow of the cooling water from the aft end to the forward end of the nozzle housing;
• a valve element concentrically disposed within the nozzle assembly and having a valve head and a valve stem, the valve head being sealable against the forward end of the nozzle housing, with the valve stem extending through the nozzle barrel and protruding past the aft end of the nozzle assembly and having a threaded portion proximate the aft end of the nozzle assembly, the valve head and the nozzle housing collectively defining a flow orifice when the valve head is axially displaced, the valve element being operative to regulate cooling water flow;
• at least one valve spring slidably mounted on the valve stem for biasing the valve head against the nozzle housing such that cooling water exiting the flow orifice may be selectively blocked and unblocked;
• a valve stop fixedly mounted on the valve stem for limiting the axial movement of the valve element;
• and
• a load nut threadably attached to the threaded portion of the valve stem for applying a spring preload to the valve spring.