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Oakdale, Bellville. 7530
Western Province
South Africa
Tel: +27 21 946-2872
Fax: +27 21 946-2873
Email: info@spraytech.co.za

Technical Information

THE SPRAY NOZZLE

The spray nozzle transforms the energy of a liquid into kinetic energy. The kinetic energy is utilized to break up the liquid into small particles, and to disperse them evenly according to the desired pattern. In some cases the kinetic energy is used to increase the penetration force of the jet. The nozzle also makes it possible to obtain pre-set capacities according to the pressure applied as can be seen from the tables in this catalogue.

CAPACITY

The capacity depends on the internal flow area and on the working pressure. In general the relationship between the capacity and the pressure is the following:

Q1 and P1 are known capacity and pressure. Q2 is the resulting capacity at desired pressure P2. All the tables of the catalog are based on water. For liquid with a specific gravity other than 1 multiply the catalog water capacity by the following conversion:

Type of nozzle

It is available a wide range of nozzles suitable to solve every kind of your spray problems. So you can choose different spray patterns, and precisely:

Hollow cone spray: type A

The liquid particles are distributed evenly forming the outer shell of a hollow cone. The area covered by the spray, falling perpendicularly to the jet, is in this case a circumference whose diameter is relative to the distance of the nozzle and the spray angle.

Full cone spray: type B

In this type of spray the internal part of the cone is also filled evenly with liquid particles. The area covered by the spray,falling perpendicularly to the jet, is in this case a circle whose diameter is relative to the distance of the nozzle and the spray angle.

Flat jet: type C

In this type the area covered by the spray falling perpendicularly in an elongate elliptical shape. The dimension of the lateral axis is relative to the distance between the nozzle and the covered area. The dimension of the longitudinal axis is relative both to the distance from the nozzle and the spray angle.

Atomizing nozzle: type E

In these nozzles the compressed air is mixed with the liquid to provide a fine atomization. From the tables you can choose the type of atomizer which better satisfies your specific requirements.

Spray angle

The spray angle is usually measured near the orifice. Increasing the spray distance the measure of the spray width becomes less exact because of gravity effect and ambient conditions. It must be considered that an increase of the viscosity of the products to spray reduces the spray angle. The table lists the theoretical coverage at various distances in relation with the spray angle.

Droplet size (atomization)

The major factors affecting droplet size are the capacity, the pressure and the spray pattern. Usually an increase of the capacity, under the same conditions of pressure, produces larger droplet size. The increase of the pressure reduces the droplet size, as well as the increase of the spray angle. Air atomizing nozzles produce the smallest droplet size, full cone nozzles produce the largest droplet size. For every spray pattern, the table shows the average droplet sizes relative to the minimum and maximum capacity values, with a pressure of 3 bar.

Impact

The spray impact depends on capacity, pressure and spray pattern. The highest impact is produced by solid stream and flat spray, the lowest one by wide full and hollow cone.

Nozzle wear

The wear effect produced on the nozzle orifice determines an increase of capacity. Under the same conditions, stainless steel life is five times longer than brass.

Classification of spray measures

Article code

The standard material of our product is indicated on the table 1. Eurospray may also supply the nozzles even with non-standard material according to the customer’s request. EUROSPRAY’s products are identified by 11 alphanumeric characters.

SPRAY NOZZLES identification method