The free passage diameter gives the approximate minimum dimension for a liquid to freely pass through a nozzle.
The free passage diameter gives the approximate minimum dimension for a liquid to freely pass through a nozzle.
The flat spray nozzle orifice is cat-eye shaped and the free passage diameter is the orifice width multiplied by a safety factor.
The typical full cone spray nozzle includes a whirler which forms a round spray area with uniform distribution.
The smallest dimension of liquid passage in the nozzle depends on the whirler.
The diameter of a sphere that can pass through the whirler is defined as free passage diameter.
For hollow cone spray nozzles without whirler and solid stream spray nozzles, the free passage diameter is either the diameter of the nozzle inlet or of the orifice, whichever is smaller.
The whirler is the bottleneck in the liquid passage and where clogging can occur. There are several types of whirlers such as X-shaped, disc-shaped, and spiral shaped.
The X-shaped whirler has the largest free passage diameter and therefore has the least risk of clogging.
The hollow cone spray nozzles AAP series, the TAA series, and the full cone spray nozzles AJP series have no whirler or other obstructions in the nozzle interiors and are therefore the most clog-resistant.
