HARBEN CENTURY, Service Manual

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Flowplant Century Pump Manual
3.2.3 Drain/Sewer
In addition to the protective clothing listed in Para 5(4), the other equipment should be used
when entering confined spaces, such as safety harness and rescue line, atmospheric
testing equipment, escape breathing apparatus and hand lamps (intrinsically safe
where appropriate).
To prevent snaking or reverse travel of a flexible hose inside the tube being cleaned, a
section of steel pipe, slightly longer than the diameter of the tube to be cleaned, should be
connected between the flexible hose and the nozzle (drain jet extension).
During drain cleaning operations it is advisable to use a coloured leader hose to act as a
warning to the operator that the hose recovery is almost complete.
In addition to Where drain or pipe jetting operations are to be carried out remote from the
high pressure pump unit, i.e. where communication between the person controlling the pump
and the equipment operator is not possible, it is essential that a remote control kit or foot
control valve is used at the work point.
3.2.4 Hoses
Care should be taken to ensure that all hoses are maintained in good condition and are of
the correct specification for the pressure being used.
Never loop the hose into an excessively tight radius, particularly adjacent to couplings.
When fitting re-usable couplings, always ensure that the current type of couplings are being
used in relation to the hose specification.
3.2.5 Underwater Recoil-less Safety Gun
The Harben Underwater Recoil-less Safety Gun is designed for use under-water only.
Extreme care should be taken to avoid rear-facing balance jets when testing the equipment
above water.
If working in shallow water, where there is a possibility of the diver surfacing inadvertently
during water blasting, care should be taken to ensure that the recoil balance jet protection
tube is sufficiently long to prevent the diver directing it at himself.
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