User Manual

Introduction 7
HYDRO EXCAVATION – ADVANTAGES
Hydro excavation tends to be most
effective with more compact soils
including frozen surfaces. Onboard
water heaters warm the water
which aids in cutting through the
soil. Water also acts as a lubricant
and helps to prolong the life of
vacuum equipment by reducing
wear on vacuum hoses and other
components in the air stream.
Hydro excavation is especially
useful for tank, pit, or general
cleaning and does not produce the
sandblasting effect common to dry
excavation.
As a rule, when speed of excavation
is the most important factor, hydro excavation is generally the
methodology of choice.
Vacuum trucks feature on-board compressed air or hydro packages
that can be purchased as options. Choosing a vacuum truck featuring
both capabilities significantly increases versatility and permits the
contractor to deal with myriad conditions. Some utilities and State
Departments of Transportation are beginning to require dry excavation
for certain applications, for example where backfilling is required for
Subsurface Utility Engineering (SUE) projects. On the other hand,
the speed of hydro excavation is too significant to overlook for general
potholing, which is why utility contractors often favor a machine with
both capabilities.
OTHER CONSIDERATIONS
Contractors should choose a vacuum system to meet specific
applications and achieve maximum job productivity. Options include
cold weather packages with water heaters to cut through frozen
ground, dual operator stations, hydraulic tool packages, off-loading
and dumping capabilities, and auxiliary tool boxes. An on-board air
compressor can provide a variety of uses such as powering pneumatic
tools. An on-board water tank to provide fresh water at a job site, or
the ability to tow an auxiliary trailer, may be other important features.
Full Size Vacuum Truck
AirVac manufactured by Guardair
VACUUM UNITS – A RANGE OF OPTIONS
Vacuum units are typically
large, expensive, truck-mounted
systems with the capacity to
hold between 1,000 and 2,000
gallons of spoil. At the other
end of the spectrum, small,
cost-effective units such
as the 82-gallon capacity AirVac,
provide a high degree of mobility
and are suited for smaller jobs.
Maneuverability and small size
provide an advantage on
crowded job sites and where
sensitive terrain might suffer
damage from heavy, truck-
mounted units.