A little while ago I wrote about Sand Traps and how they
should be inspected and cleaned regularly. This week we’ll look at the effect
sand has on your irrigation system.
In general terms, sand inside an irrigation system = bad!
Sprinkler spray pattern
Just like sand-paper or sand blasting, sand suspended in
water inside your irrigator is abrasive and will cause expedited wear on your
system. This wear occurs anywhere exposed to the sand. It will start at the
pump, causing impellors to wear faster, go through your mainline and headworks.
If you have a mechanical flow meter, this will suffer. The sand then gets into
the riser and makes its way along your span-pipes causing wear on the
galvanising all the way along. Some of the sand will make its way up into the
goosenecks and then down into your regulators and sprinkler nozzles, then onto
the sprinkler plates. And guess what – it’s still abrasive and causing wear on
these components too!
The main two problems caused by sand wear are
1.
Decreased life expectancy
2.
Decreased performance
As components like regulators and nozzles experience wear,
they will start letting more and more water through, the more water that is
going through, the greater the wear and the cycle continues. Your nicely calibrated
system at the beginning of its life will soon start to over-apply water and as
it is doing this it is also causing more wear on the sprinkler plate which will
distort the sprinkler’s application pattern.
If you have a lot of sand in your system, other than emptying
the sand trap frequently, you should also be aware that your system will need
checking and re-calibrating more frequently to account for the wearing effect.
In order to mitigate some of the bad effects caused, you
might want to consider a sand separation system such as the lakos sand
separator filter pictured below. This type of filter will remove 98% of
sand-like particle matter down to 200 mesh (74 micron) with low and steady
pressure loss of only 0.137 to 0.413 bar.
Lakos sand separation system
For more information about sand filtration systems, contact
your local Lindsay
dealer.