RG / RGT (en)

It should be noted that the nominal diameter of a scouring ball, type RG and RGT, is the diameter of the uncoated ball.

Both Scouring Balls, Type RG and Type RGT are available in a range of standard sizes from 15 to 45 mm diameter, in 1 mm steps.

Each in a standard medium grade of hardness. Non-standard sizes or hardness’s are available on request.

Our Scouring Balls are coated with fine particles of granule, bonded to the sponge ball using a specially selected adhesive.

Coating particle size:

400 µm – 600 µm.

The coating material has been specifically chosen so as to have a hardness less than that of the commercially-available grades of titanium condenser tubing, in order to prevent wear of the underlying tube material:

Coating: average Hv 106; Titanium tubing (Grade 2): Hv 130 min.; typically 145.

To ensure that all the tubes are cleaned, the specific gravity of the watered scouring balls is such that they have a sinking velocity of only 2 - 6 cm/second in typical cooling waters.

Immediately prior to use, the balls are watered by squeezing them under water in the ball vessel several times to expel air.

Our sponge ball and coating adhesive have both been specially chosen for service in power plants and similar applications. The scouring balls are thus resistant to virtually all types of cooling water.

The effectiveness of scouring balls is strongly dependent on the nature of the fouled layer to be removed.

Type RGT cleaning balls can be used where deposits are soft and not particularly adherent. If the deposits are scale-like and more difficult to remove our Type RG cleaning balls are recommended.

For a given heat exchanger or condenser, the pressure drop between the inlet and the outlet dictates the maximum ball oversize which can be used while still ensuring that the balls do not get stuck in the tubes. Other things being equal, the choice of a ring coated ball permits lager oversize than would be possible with fully coated balls. This in turn means that the cleaning pressure exerted by the balls on the tube surface/fouled layer is greater and thus the cleaning more rapid.

As the scouring balls can subsequently be used further, quasi as sponge balls (see below), increased ball life is an additional benefit.

It should also be noted that the relatively soft nature of the deposits to be removed means that tracking (i.e. orientation of the coating ring in a specific direction during repeated ball passages through a given tube) is not a problem and ensures that the whole tube surface is cleaned.

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

Hard scales and corroded surfaces have a particularly detrimental effect on ball life.

In relatively smooth tubes, the scouring ball life Is of the order of 2000 tube passes, i.e. equivalent to about 16 hours' continuous operation of the on-line tube cleaning system.

In contrast to the use of abrasive balls, where there is a risk of tube wear with excessive use, the underlying tube material is unaffected by the cleaning action of the scouring ball (Type RG or RGT)on titanium tubes. Consequently, scouring balls can be used continually or at regular intervals.

Furthermore, once the coating has worn away, the balls will still have a cleaning effect as long as they are larger in diameter than the internal diameter of the tubes to be cleaned, albeit somewhat less aggressive than that of the balls with a coating.