Steam desuperheater with variable section spray nozzle
The steam desuperheater DA-O provides reliable steam temperature control. The connection to the steam pipe as well as the spray water pipe are both flanged to facilitate service access.
The DA-O is used for desuperheating of steam in small and medium sized pipes and is especially useful when the cooling water temperature is close to saturation.
The DA-O injection nozzle is screwed onto the body and secured by a lock washer. The nozzle itself has a spring loaded plug which extends as the pressure in the nozzle holder increases. The amount of water being injected by each nozzle is determined by a number of factors, including the diameter of the nozzle body opening, adjustment of the spring, and the pressure differential between the steam inside the desuperheater and the water pipeline.
The cooling water enters the inner nozzle chamber through a number of water channels. Water is rotated around the nozzle plug thanks to the special arrangement of the water channels. The plug and the seat are designed to create maximum water velocity at the nozzle edge point. The high velocity of the water when it leaves the nozzle guarantees fine atomisation, quickly evaporating the spray water.
In order to maintain a constant pressure inside the injection nozzle, the latter is preloaded by a spring calibrated in function of the water/steam differential pressure.
More info : https://www.imi-critical.com/products/da-o/