Matching tank cleaners to tank size

One of the biggest factors in choosing the correct tank cleaner will be the size of the tank in question.

Cleaning radius

Each of our tank cleaning system comes rated with an effective cleaning radius.  If the horizontal distance from the tank cleaning head or nozzle to the furthest wall of the tank is greater than this rated distance then effective cleaning is unlikely.  Conversely the further within the cleaning radius the furthest point of the tank wall lies the more effective the cleaning action will be.  This is particularly true of the larger impingement tank cleaners.

The cleaning radius of most tank cleaning systems will be affected by the flow rate and pressure of the water supply.  As pressure and flow rate are increased the effective cleaning radius also increases but after a certain point there are diminishing returns and so a practical upper limit on cleaning radius is in place for each type of tank cleaner.

For some helpful guides on selecting tank wash systems, click on the icons to watch the videos below:

 Cleaning or scrubbing or wetting?

Tank cleaning manufacturers often use these terms interchangeably and this causes some confusion. The wetting radius is the distance at which the nozzle or machine will cause the wetting of the surface. This is of course very different to the distance at which the machine in question will effectively clean. Typically the maximum distance at which an effective clean will occur is called the cleaning or scrubbing distance.  It should be noted, however, that the term “effective clean” is itself imprecise and ambiguous.

Smaller tanks (below 1 metre radius)

Static nozzles or spray balls may well be suitable for small tanks.  The practical upper limit for these types of nozzles is a radius of around 3-4 metres for some of the larger spray balls but typically they will be used in vessels much smaller than this.  It should be noted that even if operating well within the cleaning radius static nozzles of all types only give a light cleaning action.  Over time the action of water will clean tough residues but this will typically be a less water efficient process than if using rotary tank cleaning systems.  For this reason for smaller tanks with tough residues rotary tank cleaners are normally recommended.

Tough residues – rotary fan, fast cycle jet cleaner 

Medium sized tanks (1 - 2 metre radius)

Rotary fan cleaners do not extend the overall cleaning radius significantly but they do deliver a more water efficient clean.  For medium sized tanks with a radius of 2-4 metres rotary spray heads are always a more efficient way to clean.  The fan jets have far more impact than the sprays from static systems and this increased mechanical action helps loosen and break down residues.  If a simple rinse is required then static nozzles or spray balls may still be suitable for medium sized tanks.  Conversely, for very tough residues, rotary jet cleaners may be suitable.

Medium residues – rotary jet or rotary fan

Light residues – rotary fan or static

Large tanks (2 - 3 metre radius)

For tanks with a 4 plus metre diameter most often the step up to rotary jet cleaners is sensible.  This sized tank is still technically within the range of rotary fan cleaners or even some of the larger spray balls but at these diameters the cleaning impact is negligible and so the smaller tank cleaning systems will require time and significant amounts of water to work.  As such, jet cleaning systems will almost always be the most efficient way of cleaning these tanks.

Tough residues – rotary jet

Medium residues – rotary jet

Light residue – rotary jet or rotary fan

Very large tanks (3 – 20 metre radius)

For tanks with diameters above 6 metres only rotary jet cleaners have sufficient reach to be effective at removing residues.  In principle multiple static nozzles could be used to perform a rinse down action but we strongly recommend jet cleaning systems for tanks of this size.  Rotary jet cleaners with a suitable water supply can produce effective cleaning jets over 20 metres long.  For the bigger end of the scale fluid pressures of 10 bar will be necessary but for smaller tanks 3-4 bar fluid pressure is often sufficient.

Tough residues – rotary jet (multiple cycles)

Medium residues – rotary jet