CLEARSTREAM JETS

Clearstream jets emit a solid stream of water to heights determined by the size of their orifice and the volume and head pressure characteristic of the pump. Usually, in all but the very smallest jets, the bore is tapered to provide a clean solid stream with a minimum of tearing of the water pattern. The smaller of these jets (from .125" to .375", and occasionally larger) are more commonly used in spray rings, spray bars, rippler bars and are discussed under that heading.

CASCADE JETS

Cascade jets present a different condition due to the orifice of the nozzle from which the line water is ejected being positioned below the surface of the pool water. The cascade jet consists of a nozzle and outer shell with the top of the outer body positioned approximately 1/2" above the surface of the pool water. The pressure of the water being emitted by the nozzle draws the pool water into the interior of the outer body where it mixes with the stream and is carried into the air. The pattern is an interesting white, frothy "Christmas tree" shape and has found favor with many fountain designers.

FOAM "BUBBLER" JETS

The foam jet is closely related to the cascade jet with respect that the orifice is mounted well below the water surface. . The foam jet differs from the cascade in its physical construction. Instead of the surrounding bell shape over the orifice, the foam jet's orifice in mounded in a brass chamber well below the water level. The air snorkel tube connects the orifice to the air above the water level. The pressure of the water being emitted by the nozzle draws the air through the snorkel tube into the orifice where it mixes with the stream and is carried into the air. The pattern created is a white, frothy "mound" shape effect. 
 
AERATING JETS

The aerating jet is an extremely popular and versatile nozzle and is probably the most widely used jet in the line. It consists of three chambers with the inner nozzle connected directly to the line. The shell of the inner chamber has vertical slots milled in it. The outer shell fits over the inner shell by means of a collar and is adjustable along the length of the inner barrel. The jet assembly is immersed in the pool to a point where the top of the outer shell is from 2" to 5" above water level. The inner barrel is extended to a somewhat higher level. The bottom ring of the outer barrel fitting snugly around the inner barrel acts as a divider over the vertical slots. Thus, the suction effect of the line water being discharged through the line nozzle creates a vacuum and pool water is drawn into the chamber through the lower half of the slots. At the same time air is drawn down through the space between the two barrels, inasmuch as this opening is above water level. This air passing into the inner chamber through the upper part of the slots is mixed with the pool water and line water, actively aerating it. As a result, the highly aerated stream rising into the air has a frothy white consistency that gives it the appearance of snow. It creates the impression of much more water mass than is actually passing through the jet and has a high reflecting quality which makes it ideal for night lighting. Because the aeration jet performs work by lifting a percentage of pool water along with the water stream, it requires a proportionately greater head pressure for a given number of feet of stream height than is associated with a stream from a smooth bore jet at the same height.

SPRAY RINGS

Another of the more commonly used spray effect devices is the spray ring. A spray ring is simply a distribution manifold around whose periphery is mounted a series of jets. The size of the pipe or tube is determined by the GPM (gallons per minute) demand of the jets, and must be of sufficient size to hold friction head pressure loss below allowable maximum for the total system. Where the demand is heavy and the desire to keep the tube diameter as small as possible, two or more pipe inlets spaced equal distant apart will permit the intake of water to be distributed to fewer jets, thus reducing GPM demand and head loss for a given size ring.

Spray rings are designed to accommodate either adjustable angle or fixed jets. Fixed jets can be mounted as close as 1" on center. Because of physical mounting characteristics, minimum distance between adjustable angle jets is 2-1/2" on center. Adjustable jets have several advantages. They are easier to align on the job. More important, they can be repositioned at will; affording the opportunity to change the water pattern from time to time to give a fresh and new appearance to the fountain. Fixed jets are positioned to the desired angle at the factory and once the holes are drilled in the ring, the angle cannot be changed except for slight alignment adjustment.

WATERCASTLE JETS

While the watercastle jet can be custom built to larger dimensions, the models listed in the catalog are most commonly used in smaller fountains. The watercastle jet will produce a two tier water pattern with a vertical center stream. Its flower like lacy pattern is most interesting and reacts well to lighting. The water spray diameter and the spray height are controlled by an internal restrictor located in the body of the jet. The jet must be fed with non-turbulent water supply that is 100% percent filtered in order to reduce maintenance and increase life to the jet. The filtration is required since the water must travel through the small diameter orifice openings located at the top of the jet.

SPHERE AND HEMISPHERE JETS

The full sphere and hemisphere jets create a glistening ball of water or half ball of water respectively when arranged properly within the pool. Both jets must be fed with non-turbulent water supply that is 100% percent filtered in order to reduce maintenance and increase life to the jet. The filtration is required since the water must travel through the small diameter copper arms before flowing out of the number of diminutive orifice deflector plates located at the end of each jet arm. When located outdoors, the full sphere jet is susceptible to wind and close attention is needed when sizing the pool.

SPECIAL EFFECT HEADS

Occasionally an architect or designer wishes a special water effect that cannot be readily provided by the use of standard heads or jets. It is difficult to anticipate the specific condition that might be presented; therefore, it is best to gather the material and information and send it to the factory for evaluation and recommendation.

The greatest task confronting a designer of fountains is to develop a concept that is artistically pleasing in a manner that will stand the test of time.

The design must also lend itself to the practical use of sound and proven equipment that will perform in a reliable manner over a period of years with a minimum of upkeep and service.