Nozzle with metal rotor and stator have to withstand extreme forces.
The material used and the surface treatments performent should
prolong the lifetime. The very high precision required for a quality
rotary nozzle are constricting the suitable materials. The corrosion
resistance is therefore second in line.
To
maintain this
fragile design it is important to implement
the right maintenance procedures.
Use clean, filtered
water to operate.
Water should
only come in contact with the nozzle when
used. Water
trapped inside
the nozzle from use, but also from
condensation caused by
the changing air temperature, has to be
removed. To have
it dried is not enough as it can clock up and still
cause galvanic corrosion. Do not use any oil. Oil may have additives
and will dry out. A restarting might not be possible or only with a
limited water film causing premature nozzle failure. If ceramic
insert are used you can not use aggressive
liquids. The
ceramic is usually
sealed in the housing
with a sealant. Do not use mechanical
forces to get a rotor turning. Marks from a screw driver on stator
or rotor make a nozzle irreparable.
The
fluid has to have the following characteristics:
-extreme
creep-ability
-dispels
water (water repellent)
-corrosion
protection
-lubricant
-not
aggressive to materials, sealants
With
the emphasis on corrosion protection the nozzle fluid
fulfills all the
requirements.