RT / RTL (en)

Type RT sponge balls are available in a range of standard sizes from 15 to 45 mm diameter, in 1 mm steps. Each size is available in a standard medium grad of hardness.

Non-standard sizes or hardness’s are available on request.

The composition of the balls is based on a natural rubber mixture containing inert filler material (ratio of filler to rubber approx. 1:2). Roughly 10-20% of the mixture is vulcanizing agents. The exact mixture has been chosen to give the optimum combination of physical properties, ball life and cleaning effect. There is no health risk associated with the ball mixture; all chemicals used are permitted for use in contact with foodstuffs.

Colouring agents added to the mixture do not influence ball properties in any way.

The standard colour is blue. Light ball colour is flieder.

The specific gravity of the cleaning ball is: 0,27 g/ccm.

To ensure that all tubes are cleaned, the watered balls should have a spezific gravity close to that of the cooling medium.

They have a sinking velocity of:

Standard ball - 6-8 cm/sec.
Light ball - 1-3 cm/sec.

The Type RT Sponge Ball has been specially chosen for service in seawater desalination plants and similar applications.

There are a number of chemical species, including oil and other hydrocarbons, which can have a detrimental effect on the performance of the balls if present in appreciable quantities; these are not common in cooling water systems. In consequence, the balls are resistant to virtually all types of cooling water.

Generally speaking, all types of sponge ball remove soft deposits of the type usually found in desalination systems, such as mud, slime or magnesium oxides. To some extent, they can limit scale formation in harder waters by removing hard drystalline scales (e. g. calcium carbonate) as nuclei. However, they are ineffective once scales have become established.

Within practical limits, the cleaning effect is not significantly affected by either ball oversize (i.e. difference between ball diameter and tube i.d.) or grade of hardness. However, the ball diameter should always exceed the internal diameter of the tube to be cleaned. The maximum permissible oversize is dictated by the available pressure drop across the heat exchanger and the need to avoid balls sticking in the tubes.

Ball life is strongly dependent on the cleaning frequency and the surface condition of the tubes to be cleaned.

It is typically about 4 weeks, but can be much longer depending on local conditions and frequency of cleaning. Scaled and corroded surface have a particularly destrimental effect on ball life. The use of other types of ball, e.g. abrasive balls, to polish raughened surfaces should be considered in case of excessive ball wear.

SCHMITZ Reinigungskugeln warrants that its cleaning balls are free from defects in material and workmanship for the life of the product. This warranty excludes normal wear and tear.

Cleaning balls should be stored carefully in a cool, dry place, away from direct sunlight. Extremes of temperature should be avoided.

To prevent deformation of the balls, it is recommended that they be stored in the boxes in which they are supplied. Experience has shown that storing more than 2 boxes high should be avoided. If the balls are removed from the box, they should be stored loosely, for the same reason.