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Keyhole Excavation
Suction excavation systems help create a
reduced excavation and by removing soil via
suction into a debris tank there is no unsightly
waste at the side of the road.
How it Works
An air flow volume of up to 32,000 m
3
/h
(32,700 cubic yards/hour) is generated by a
radial fan, creating a vacuum of up to
40,000 Pa (5.84 psi) of head. The suction hose • Suction excavation is much faster than
is moved three dimensionally via a hydraulically hand digging.
operated boom. All kinds of material, up to There are significant additional hidden cost
250 mm (9.84") in diameter, can be sucked up benefits resulting from the use of suction
throught the intake nozzle. excavation technology.
These can be summarised as follows:
Key Benefits • Minimise cable and services strikes.
• Reduced utility strikes - no evidence of • Significant mitigation of risk associated with
service strikes using suction excavation in consequential costs levied against the
s utility envelopes become other countries. business.
A
more crowded, preventing • Reduced size of excavations - minimised • Reduced quantities of spoil and waste and
damage to utilities has waste costs. hence reduced disposal cost.
become increasingly • Compacted clays can be excavated. • Much increased efficient use of the work
challenging. One solution • No spoil on site - less traffic disruption. gangs resulting from the reduced need to
is suction excavation; an insight • Improved access over Grabs as no side repair unforeseen services disruption, hence
to which follows by Force One capture problems. more time to work on the core activity which
Utilities Ltd. • Good excavation output. ultimately leads to greater capacity.
Suction excavators use high-pressure water • Reduction in plant and transport logistics, as
or air to quickly dig precisely controlled holes to In today’s climate suction excavators offer a the work gangs switch from traditional
uncover buried utilities. This is done by keyhole safer way to work underground as they are methods to suction extraction. Subsequent
excavation using suction to physically uncover non-aggressive and non-invasive. The onboard reduction in logistics cost base.
lines and cables to confirm their exact location. tools used in conjunction with the vehicle
This form of excavation is becoming a widely ensure that all apparatus can be exposed Where work is done from above ground
used practice on a growing number of safely and cleaned out on all sides without through a small suction excavation, it can easily
construction sites. any problems. increase productivity compared with
Conventional repair methods often require mechanical methods and is far safer.
large open excavations, followed by the Advantages of Suction Excavation Finally, small excavations made by the
removal and disposal of unwanted soils. This • Rapid response - could be undertaken suction excavation are easier and less
form of repair method normally uses several without utility plans or cat scanning in expensive to fill and repair than the larger ones
pieces of equipment: mini excavators and emergencies. made by mechanical equipment.
trailers, pavement breakers and safety barriers. • Even with hand tools it’s easy to damage a Whilst operations can realise significant
Plus additional area is needed for backfill buried utility and, of course, backhoes are at savings using keyhole technologies, clients
material and unsightly waste at the side of the risk of causing utility strikes. will also benefit through less disruption and
excavation. Excavations can also be a major • Excavations created by a suction excavator noise, quicker repair times, fewer and
cause of traffic disruption and in some areas can be faster and easier to patch than the shorter service interruptions, and reduced
council's have limitations on the time frames much larger hole left by mini excavators or by traffic inconveniences.
when utilities can be excavated. hand digging.
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