Technical data

44
BUNDED TANKS
For domestic applications
A bund is a structure which surrounds a tank. It is designed to
contain any accidental leakage or spillage of the contents,
thus preventing pollution of the environment. A traditional
bund, sometimes known as a catchpit, is usually constructed
of rendered brick or blockwork and is separate from the tank.
A Balmoral bunded tank is an integral combination of a fuel oil
tank and a bund (tank within a tank). Both the inner and outer
tanks are manufactured from rotationally moulded
polyethylene. The product avoids the need to construct a
traditional brick built bund, provides a compact installation
and, being enclosed, eliminates the need to dispose of
accumulated rainwater and debris and minimises the risk of a
‘jetting’ type of leakage from a punctured tank raised above
the walls of a traditional style of bund.
All bunds must fulfil the following requirements:
Q must not have a drain outlet
Q must be completely impermeable to liquids
Q must contain all fuel supply/filling accessories within the
catchment area
Q must contain 110% of the capacity of a single tank installation
We advise all Balmoral bund installations to be inspected
regularly, eg once a year or before filling. Any liquid overspill
contained within the outer bund ‘catchpit area’ must be
removed to prevent reaching the overflow level and to avoid
buoyancy of the inner tank.
Parts supplied as standard:
Q Either a factory fitted 1”BSP (male) bottom offtake
connection or a 10mm compression fitting for top offtake
Q This fitting provides an offtake suitable for gravity feed
situations whilst maintaining an essential seal of the inner
and outer tanks
Q 2” BSP (male) fill point with cap
Q 105mm diameter (4”) aperture with flush fitting cover for
desludging and inspection of inner tank
Q Lockable hinged manhole cover on outer tank
Q Mechanical overfill prevention valve
Q Electronic contents gauge
Domestic bunded tank options
Top fill/bottom offtake (Figure 1 on page 21)
Recommended combination of outlet accessories on bottom
offtake bunded tank.
Top fill/top offtake (Figure 2 on page 21)
This option has been primarily designed for domestic
heating applications where bottom offtake bunded tanks, in
some cases, may not be permitted.
Supplied as standard with the following:
Q A factory fitted 10mm brass compression fitting with
internal copper extractor tube. This fitting provides an
offtake suitable for most domestic fuel oil installations
and provides enhanced environmental protection by
avoiding low-level penetrations through the bund. A
suitable pump to extract the tank contents and a non
return valve on the pipeline may be required. A hole
should be drilled in the top of the tank (see Figure 3) for
the fuel supply pipe. Check that there are no air leaks in
the pipeline once assembled
Q 2” BSP (male) fill point with cap
Q 105mm diameter (4”) aperture with flush fitting cover
Q Lockable hinged manhole cover on outer tank