Impact sprinkler
Encyclopedia
Irrigation sprinkler
Irrigation sprinklers are sprinklers used on farms, golf courses, and yards, to provide water to vegetation and plants in the event of drought. They may also be used for recreation, as a cooling system, or to keep down the amount of airborne dust....
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Development
The original horizontal action impact drive sprinkler was invented by Los AngelesLos Ángeles
Los Ángeles is the capital of the province of Biobío, in the commune of the same name, in Region VIII , in the center-south of Chile. It is located between the Laja and Biobío rivers. The population is 123,445 inhabitants...
citrus farmer Orton Englehardt in 1933 and patented in 1935 (US Patent #1,997,901). Orton later sold it to Clem and Mary LaFetra who manufactured and marketed it under the brand name Rain Bird
Rain Bird
Rain Bird Corporation is a large privately held manufacturer and provider of irrigation products and services, based in Azusa, California.-History:...
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Design and operation
The sprinkler pivots on a bearingBearing (mechanical)
A bearing is a device to allow constrained relative motion between two or more parts, typically rotation or linear movement. Bearings may be classified broadly according to the motions they allow and according to their principle of operation as well as by the directions of applied loads they can...
on top of its threaded
Screw thread
A screw thread, often shortened to thread, is a helical structure used to convert between rotational and linear movement or force. A screw thread is a ridge wrapped around a cylinder or cone in the form of a helix, with the former being called a straight thread and the latter called a tapered thread...
attachment nut. It is driven in a circular motion by a spring-loaded arm pushed back by the water stream which returns to "impact" the stream. This breaks up the water stream enabling a uniform watering area around the sprinkler.
Nozzle
A nozzle is a device designed to control the direction or characteristics of a fluid flow as it exits an enclosed chamber or pipe via an orifice....
(see image), which fills the close range watering coverage role provided by the rapid "return cycle" on part-circle heads.
The uninterrupted flow path of impact heads makes them less vulnerable to damage and clogging by dirt and sand in the water. Thus, they are suitable for systems fed by well
Water well
A water well is an excavation or structure created in the ground by digging, driving, boring or drilling to access groundwater in underground aquifers. The well water is drawn by an electric submersible pump, a trash pump, a vertical turbine pump, a handpump or a mechanical pump...
water.
One defining feature of impact heads is they almost always have male pipe threads, as opposed to the female threads found on virtually all other sprinkler types.
The sprinkler head was originally manufactured from metal. Since the 1970s, they have also been manufactured from thermoplastics for improved corrosion resistance.
Usage
The impact sprinkler's long throw radius and uniform water distribution re-creates the effect of natural rainfall, and the device quickly replaced the centuries-old technique of furrow irrigation, in which trenches were dug between rows of crops and flooded.Variations
An underground pop-up version of the impact sprinkler was introduced as a way to avoid the problem of having to carefully and time consumingly mow around overground sprinkler heads. When not in operation, these sprinklers disappeared out of sight below turf level.Although largely replaced by gear-driven "rotor heads" by the 1990s, impact sprinklers still have many advantages, including uniformity of coverage, sand and grit resistance, and operation at lower water pressures.