The hose is the part of a spraying set that fails first, and almost always for one of three reasons: it was rated below the pump, it was the wrong diameter for its length, or it was coiled wet and left in the sun.
Burst pressure is not working pressure
Hose carries two numbers. Working pressure is what it is built to handle continuously. Burst pressure is where it fails — usually several times higher, and it is not a figure to design around.
An HTP pump builds real pressure, and the spike when a spray gun is closed sharply is higher than the gauge reading at the pump. The hose has to be rated for the pump's working pressure with margin above it, not matched to it. A hose chosen on price and rated just under the pump will hold for a season and then split, usually at a coupling.
Diameter is a trade between flow and weight
A wider hose loses less pressure over its length. A narrower one is lighter to drag down a row.
The loss builds with distance, so diameter matters more the longer the run. A narrow hose is fine on a short line from the pump to a nearby plot, and noticeably weak at the nozzle once the run gets long — the gun feels fine near the pump and poor at the far end of the field.
If one length has to cover the whole holding, size for the far end, not for the convenient end.
Where hose actually fails
- At the coupling. Flexing right behind a clamp fatigues the wall. A short length of stiffer sleeve behind the coupling stops the hose folding at that point.
- At a kink. Once a hose has kinked, the wall is damaged even after it straightens. That spot becomes the next burst.
- In storage. Chemical left inside overnight attacks the lining from within, and sunlight attacks it from outside.
How to make hose last a season longer
- Flush with clean water after every spraying day, gun included.
- Drain it — do not coil a hose full of water.
- Coil loosely in wide loops; tight coils set permanent kinks.
- Store out of direct sun.
- Replace a length that has burst once, rather than patching and carrying on.
What to tell the supplier
Three things get you the right hose: the pump you are running it from, the longest run you need, and whether it will be dragged over stubble or stay on a reel. Everything else follows.
J.P. Agro Industries manufactures HTP power sprayers at its Anand Parbat works in Delhi and supplies agriculture spray hose by the reel, along with wear parts for the whole JP Kissan range. Tell us the pump and the run and we will match the hose to it.