Basics of
Pressure Washer
Pressure washing or power washing is the use of
high-pressure water spray to remove
loose paint,
mold, grime, dust, mud, chewing gum and dirt from
surfaces and objects such
as buildings, vehicles
and concrete surfaces. The volume of a
mechanical pressure washer
is expressed in
gallons or liters per minute. There's a good
scientific reason why water
gets
things so clean: its molecules have a slight
electrical polarity (one end is positively
charged
and the other is negatively charged), so they tend
to stick to things all by
themselves.
Detergents (soap chemicals) help
water to do its job even better by breaking down
gunge and grease and making it easier for water
to flush away. But some kinds of ground-on dirt
just won't budge, no matter how hard you try.
That's when a pressure washer comes in really
handy. It uses a narrow, high-pressure jet of hot or
cold water to blast dirt free. Because the water is
traveling fast, it hits the dirty surface with
high kinetic energy, knocking dirt and dust away
like a constant rain of tiny hammer blows. It's only
water, though, so it doesn't damage most hard
surfaces.
Here's a quick summary of the basic principle:
- Cold water flows in from a faucet (tap) through another hose and is filtered on the way in.
- An electric motor or diesel engine powers the washer.
- The pump squirts out the water through the reinforced, high-pressure exit hose (and whatever attachment is fixed onto it).
The narrow nozzle on these attachments helps to increase the pressure of the water jet even more. The high-pressure of the jet not only cleans more effectively but means you're wasting around 80 percent less water than if you used an ordinary low-pressure hosepipe (which is more economical if your water is metered).
What is on the inside of a Pressure Washer? In reality, a pressure washer is quite a bit more complex inside. There are several pumps, for a start, and for safety reasons quite a lot of attention is paid to keeping the wet parts of the machine completely insulated from all the electrical parts.
- Electric motor.
- Insulating plastic foil: This ensures no water penetrates inside the motor.
- Central shaft of the motor spins around at high speed, powering the water pump.
- Reciprocating water pump: The motor turns around (rotates), but the pump moves back and forth (reciprocates) to convert the water to a high-pressure jet. There are several pump units inside a pressure washer and one is shown here.
- Pump piston: This is the chamber where water is pumped to high pressure.
- Water pipe: This is where water is sucked in and pumped out.
