8.
Will the Hoses
Stay
Outdoors
?
Sunlight, ozone, and temperatures all break
down (or dry out) hoses. Once a hose dries out,
it becomes hard, brittle, and loses its ability to
expand under pressure. In extreme cases,
dried-out hoses will even crack.
Extreme cold can actually freeze the rubber
compound in hoses, causing them to crack when
bent. The colder hoses become, the less flexible
they are. This is why it is very important to let
hoses warm up before operating equipment so
the hoses can resist the sudden shock placed
on them by the increased pressure.
Plastic hoses made from clear polyvinyl chloride
(
PVC) and semi-translucent ethyl vinyl acetate
(
EVA) become hard and brittle when temperatures
are cold and soften when temperatures rise.
Sunlight can destroy these hose types even
though the tubing material may contain an
added ultraviolet protective material.
PVC tubing is a clear vinyl product that is
widely used, but as a general rule it is rather
limited in what it can be used for. PVC tubing
is commonly used for sight gauges when one
needs to see how much product is in a stainless
steel or fiberglass tank. PVC tubing has no
pressure rating and is not reinforced.
Over extended periods, PVC tubing is
incompatible with most chemicals. Chemicals
such as pesticides soften the plastic resin and
cause the hose to stretch. Sunlight easily degrades
PVC tubing. Since these hoses are left outdoors
Hoses exposed to
constant sunlight
(
like those shown
here) will degrade.
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