Kelair's Viking pumps speed up road tanker transfer
What's so special about road tanker unloading viscous
fluids compared to normal pumping duties with
viscous fluids? Speed! Normally our customers require
the road tanker emptied in around one hour -
less if possible as it's costly to have the tanker standing
by for any length of time.
So what is the difficulty with pumping viscous duties at
speed? There is generally no difficulty with the pumping,
once the right pump is selected. The difficulty lies
in getting the fluid to the pump fast enough which
means feeding the pump fast. If pumping is required
faster than fluid can be drawn from the tanker, the
pump will 'starve' for product, ending in cavitation, and
with the tanker still being on-site for possibly another
two to four hours.
With viscous pumping, pipework is always important.
This is exacerbated with road tanker unloading. For
typical viscous fluid transfer from a permanentlylocated
holding tank, the positive displacement pump
should be situated directly under or close beside the
tank. Suction pipework is typically relatively short with
few bends and valves (and sometimes suction strainers
with minimal losses).
Road tankers on the other hand are usually parked a
few metres from the pump. Flexible hoses to the suction
end of the pump may be quite long and convoluted.
Often 3" diameter hose is used, with bends and
twists. As stated, if fast pumping is required, getting
fluid to the pump just as fast is also required. The
hoses may (all too often) have just too many frictional
losses for viscous fluids.
Working closely with one of our customers DIC
Graphics Australia Pty Ltd, Kelair assisted with calculating
fluid/pipe frictional losses from the road tanker
to the pump's suction port. We advised what size
pipework would allow the flow of liquid to pass freely,
to 'support' the duty that the pump was required to
perform and recommended a Viking 4124A model.
Pictured above, the pump's duty is unloading a
tanker full of viscous raw materials at viscosities to
2,000 cPs. The flexible hose was upsized to 4" diameter,
larger than the usual 3".
For OH&S reasons
a chain support was installed to handle the weight of
the hose when full. The viscosity and flowrate of the
fluid dictated the maximum permissible length for the
4" diameter hose but it was too short to reach the
tanker, so it was recommended a length of 6" diameter
stainless steel line between the pump and the
hose be included.
The fluid passing through the 6" line would, of
course, have the same flowrate as through the 4"
hose, but at reduced velocity. Consequently, frictional
losses are kept to a minimum, and the pump is
able to be 'fed' fast enough.
The road tankers arrive full at DIC Graphics. Within
an hour or so, they leave empty, having pumped all
their contents into the large storage tanks
For further information contact:
Kelair Pumps Australia Pty Ltd
Address: 215 Walters Road, Arndell Park, NSW, 2148
Phone: 02 9678 9....
Fax: 02 9678 9....
Web: www.kelairpumps.com.au
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