Flowserve Desuperheaters - Manual (Page 5)

5
Desuperheaters FCD VLENIM0115-00 – 09/11
flowserve.com
MaxCool MCX Nozzle
The MaxCool MCX nozzle is a variable area hollow cone nozzle that produces a fine droplet spray mist.
Figure 4 shows a cross-section of the nozzle assembly with the parts identified. The maximum range-
ability for the MaxCool MCX nozzle is approximately 20:1.
The plug is assembled through the seat and is biased against the seat with a spring. The spring is held
in place with a retainer that is screwed onto the plug. The retainer limits the stroke of the plug to ensure
proper water atomization. A castle nut with an expansion pin or a bent washer locks the assembly
together.
The geometry of the nozzle assembly is optimized to provide efficient cooling by minimizing water
droplet size. When the Δp between the cooling water and the steam is sufficient to overcome the preload
of the spring, the plug moves away from the seat and cooling water circulates through the nozzle open-
ings. As the water moves down the conical shaped plug and exits past the sharp edges of the narrow
plug opening, the cooling water is atomized into a fine spray mist.
Figure 4: MaxCool MCX Nozzle Assembly Cross-Section
Castle Nut
Expansion Pin
Spring
Mounting
Thread
Seat
Retainer
Stroke Length
Nozzle Openings
Nozzle Diameter
Plug