
Factory Farming
A Suffolk fabricator has just installed an 8m tandem press brake, one of only a few of
its kind in the UK. Steed Webzell went along to see
New headquarters on a disused US Air Force
base in the Suffolk countryside is the unlikely
location for John Harvey Engineering Ltd. That
said, this progressive OEM and subcontract
fabricator is perfectly at home in its rural
surroundings as its chief industry of supply is
agriculture, with 90 per cent of its customers
based locally in East Anglia.
Established in 1980 primarily as a
manufacturer of free range outdoor
equipment for farm animals, John Harvey
Engineering today produces a wide range of
livestock shelter and accommodation such as
farrowing huts, dry sow huts and service huts
(all for pigs), along with ancillary equipment
such as wallows, drinker bars and
feeders/hoppers. The company also
manufactures a range of units for free range
poultry farming. All sawing, shearing,
profiling, bending, welding and assembly
operations take place at the company’s facility
on Parham Airfield, Framlingham, Suffolk.
With business brisk, John Harvey
Engineering was recently encountering a
bottleneck on its existing 5m press brake. Also,
the company began to secure contracts that
required the bending of 6m components.
“The addition of extension horns for the bed
and ram overcame this difficulty, but at the
expense of long set-up times,” explains
company founder John Harvey. “And it didn’t
solve the bottleneck – we still only had one
machine.” Entering the market for a
replacement, the company became attracted
to the idea of a tandem model, which would
not only provide the separate flexibility of two
independently controlled machines, but also
that of a stand-alone press brake – switching
between the two capabilities within a matter of
30 minutes. Having studied a number of
potential models, it was a Durma E-40200
synchro hydraulic CNC press brake supplied
by UK agent Axe & Status that eventually won
the day.
“The Durma is a competitively-priced, high
quality machine from an established
manufacturer that features widely available
spare parts,” states Mr Harvey. “Furthermore,
there is a foolproof way of ensuring the two
controls are linked correctly for tandem
operations before the ‘go’ button is pressed,”
he says. “On some machines you don’t find
out until you have an 8m piece of scrap steel
and a set of twisted tooling.”
The company typically uses the machine to
bend 2-3mm thick mild steel, although
occasionally up to 8mm. Batch sizes are fairly
small – usually between 100 and 200-off –
hence quick and easy set-up is paramount.
“The Durma has halved our set-up times in
comparison with our old press brake,” says
Mr Harvey, “while our apprehension of taking
on 20ft work has been completely eroded.” The Durma E-40200 can be used as two
individually controlled 4m, 200T press brakes,
or as a stand-alone 8m, 400T machine. It
features total ram control, which allows the
operator to program very slow pressing and
return speeds when manipulating large sheets.
This greatly improves handling as the sheet is
pushed into the lower die to create the bend.
By slowing the pressing speed down to a
'creep' it is possible to virtually eliminate
conventional sheet 'whip up'.
Operators can also program the ram to rise
very slowly for a short distance after
completing a bend, then stop and pause while
the operator has a chance to take the sheet
back under his control, instead of the ram
simply releasing the sheet at the bottom of its
stroke and immediately returning to the top.
This not only improves material handling but
can increase part quality by virtually
eliminating 'dishing or bowling' around the
bend area. Word is spreading fast about the
company’s new centrepiece, with new
subcontract orders already arriving from
sectors such as waste recycling, construction
and highways.
“There can’t be many machines like this in
the UK, let alone Suffolk,” says Mr Harvey, “so
it’s easy to see why it’s attracting so much
interest.”
Article reproduced with kind permission from Engineering Subcontractor- June 2008
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