Rotary Heads

A rotary head is a type of spray head that can work well in windy conditions. Rotary heads:

• Rotate to provide several streams of water
• Produce a characteristically thick stream, which makes them effective in cutting through high winds
• Contain pressure-compensating screens that allow for a consistent spread and speed of water
• Generally requre a slightly higher design pressure than other spray systems (a minimum of 40 PSI) to deliver the water out to the desired radius. (Because design pressure encompasses the pressure at the last head, remember to add on to that loss for the system.)
• Should not be spaced beyond head-to-head coverage
• These heads tend to have low precipitation rates, so are good on sloped conditions.
• Are generally matched precipitation. Unlike most rotor heads, they will apply a uniform amount of water if you mix different arc patterns and radius nozzles on the same valve.

The terms "rotary,"  "rotating," and "stream rotor" are used for the same type of head (Hunter MP Rotator, Rainbird Rotary, Toro Precision Rotating). Irrigation F/X refers to all these heads as “rotary” heads. These heads have multiple streams of water that rotate around the rotor. Essentially, they are spray head type bodies with a small mini-rotor as the nozzle type. They typically have a larger radius range than that of spray heads – about 12 to 30 feet (3.7 to 9 m).

For information on working with rotary heads using our software, see our documentation section on Placing Rotary Heads in a Drawing.

Design Pressure

Most rotary types need at least 40 psi design pressure to get the water out to the desired radius. Be ready to have slightly higher pressures available than with spray systems. Because design pressure is the pressure at the last head, you should add on to that loss for the system.

Spacing

Rotary heads are extremely sensitive to spacing issues and are affected by wind, so they are best not used in windy situations. We recommend avoiding spacing these heads beyond head-to-head coverage.

Flow

These heads tend to have low precipitation rates, so they are good on sloped conditions. Rotary heads are generally matched precipitation. Thus, unlike most rotor heads, they will apply a uniform amount of water if you mix different arc patterns and radius nozzles on the same valve.

Video Breakdown

Jake Lott, Land F/X: Rotary Heads