While the basic functionality of gear-driven irrigation rotors has not changed over the years, many features have evolved to improve efficiency, durability and reliability.
“Rotors are more efficient than they have ever been,” says Orion Goe, product marketing manager for Toro. “Even though they may look the same on the outside, actually using the rotors, whether it be changing the nozzle or setting the arc, is becoming easier.”
Plastics used in irrigation systems are being specifically formulated to withstand pesticides, fertilizers and other chemical treatments used on landscapes, says Matt Hall, product marketing Manager for Irritrol hydraulics. He says the materials used to make rotors are more durable and perform more consistently than in previous years.
Stainless steel and brass are also being used to increase the life of irrigation systems. Rain Bird’s latest rotors, for example, offer stainless steel turrets and a brass reinforced stem to help protect the rotors in high traffic areas such as public parks and sports fields, says Erin Karschnik, product manager for rotors at Rain Bird.
“These features protect against vandals and provide greater resistance to impact when the turret is extended,” Karschnik says.
In addition to knowing the intended use of the turf, specifics like water source quality and the topography of the installation site are critical factors to consider when designing the system and selecting a rotor and its feature set, Matt Hall says.
“Before you dig any holes or put any trenches in, specify a rotor and a nozzle that works with the site you have,” he says. “Installing rotors at the incorrect spacing is probably the biggest issue a contractor can have, because once you put the sod down, you can’t really dig it all up and redo it.”
A contractor can choose the product with the most bells and whistles, but it will only be beneficial if the upfront planning was done properly, says Steve Hoveln, product manager for rotors, valves and accessories at Hunter Industries.
“There are many times when we receive calls where the rotors are spaced too far apart, the water pressure is too low and there are brown spots everywhere,” Hoveln says. “Unfortunately, there’s no easy fix for that. However, if the upfront planning was better, the rotors could have been spaced closer together so that selecting a smaller flow rate nozzle would increase the pressure and allow better coverage.”
Having a good layout and using appropriate water pressure eliminates many common irrigation problems including misting, wind drift and water waste. Features like matched precipitation rate nozzles make achieving this much simpler, Karschnik says.
“Similar to how you install sprays, you simply space the rotors at 25, 30 or 35 feet and install a quarter-, third-, half-, or full circle- nozzle,” Karschnik says.
Likewise, Intelligent Flow Technology from K-Rain makes water flow adjustments automatic, proportional and simultaneous when contractors make adjustments to the arc and radius, says Rick Hall, technical director and finished goods quality manager at K-Rain.
“When you are reducing spray distances, it is very hard to maintain matched precipitation rates when you are not also reducing your flow,” Rick Hall says. “There are only so many nozzles available but infinite possibilities in landscaping. Implementing a flow control device eliminates the need for a break up screw or replacement nozzle.”
Other user-friendly features in the latest rotors include a top arc indicator and tool-free arc adjustment, such as in Toro’s T5 RapidSet rotor, Goe says.
“It is the first rotor to allow arc adjustment without the need for a screwdriver or any kind of tools,” he says. “You simply turn the nozzle turret by hand to the desired arc, and you’re done.”
In Rain Bird’s 5000 Series Plus model, flow shut-off technology allows the contractor to work with the lateral line pressurized and the turret extended, but no water flow through the rotor, Karschnik says.
“This feature facilitates installation and maintenance such as inserting or changing nozzles, setting spray patterns or troubleshooting lateral lines,” she says. “It is also useful for controlling watering in a zone when preparing for seeding and aerating, by shutting off water flow at the rotor, not the valve.”
A common culprit for clogged rotors or deteriorating wiper seals is the quality of the water moving through the system. Although rotors are designed to be tolerate debris, it is best to filter dirty water sources to ensure long rotor life.
“Wiper seal leaks are one of the largest complaints by contractors,” Karschnik says. “Rain Bird’s triple blade design cleans debris from the turret as it retracts and creates a seal that prevents leaks both during and after operation.”
Nozzles are key.
You could have great spacing and good water pressure, but if you put the wrong nozzle in, all of that planning is shot, Goe says. “Nozzle selection is a big part of continued rotor performance over time,” he says.
Contractors should train their crews to install rotor heads level and at grade. Hoveln reminds contractors that nozzles are engineered to deliver the appropriate amount of water along the entire radius, but only when the nozzle retainer screw is not used as a nozzle diffuser screw.
“When the screw is used to diffuse the stream, all of the hard work put into the nozzle for efficiency goes out the window,” he says.
As irrigation technology changes, contractors should be open-minded about new products, Goe says.
“Whether it’s a retrofit or new installation, there may be a better tool for the job that is more efficient, easier to install, easier to adjust, and that will save time on the job site and money for the homeowner,” he says. “Don’t shortchange yourself by not keeping up with all of the products out there just because you’ve done it one way all of these years.”L&L