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Shrink Wrap
> Shrink Wrap Machines
> Shrink Wrap Machinery
Seal & Shrink Wrap Machinery
Shrink wrap equipment consists of an L - sealer with an enlarged
base to store a fan together with heaters, the whole topped with a plastic see-through
hood. When the machine is switched on, the heaters build up a store of heat which
is utilised when the machine is cycled. As the hood, which incorporates the L - Sealer, is
closed, the heaters are uncovered. At the end of the sealing cycle, the fan is engaged
to circulate heat around the pack. The operator can choose a seal only function.
This particular configuration of equipment was first brought to market three decades
ago. At that time, the conjunction of a shrink function contained
within the body of a sealer was protected by a patent. As a consequence, supply
was restricted.
At the same time, the machines were not as sophisticated as they are today in terms
of performance, whilst the market demanded machines with greater output. The desire
for faster production speeds had as much to do with the limitation of running PVC
shrink film at speed as it did with the relative lack of sophistication of conventional
manual, semi and fully automatic machines.
The seal and shrink wrap equipment, conventionally called a
Chamber machine, suffered then and continues to suffer now from an inherent
inability to produce at a particularly fast rate. One must consider that whilst
the seal time for shrink film is in the order of one second, the
shrink time for any pack is in the order of four to five seconds. When one adds
the feeding and unloading time, one inevitably sees a total cycle time in the order
of ten seconds. Hence one must consider output limited to a maximum of six packs
per minute. Generally, a speed in the order of four to five packs per minute only,
should be considered.
Historically, the consequence of the speed restriction caused Chamber or
Bubble machines to achieve only a certain market presence. Users were instead
pre-occupied with high speed and necessarily high value and high complexity equipment.
However, the penetration of these machines precipitated the reconsideration of the
value of having good performance from low cost, easy to use machinery with zero
set up time.
Over the same period, the Bubble machines improved in their ability to offer consistent
seal and shrink on all available shrink wrap films. This latter attribute has come
to the forefront particularly in the last few years where Bubble machines have been
specifically built to perform well on the latest generation of polyolefin shrink
films.
As a consequence, over the last several years, Chamber equipment has found an increasing
presence in the market. Customers appreciate the very low physical size, the ability
to position the machine anywhere, the very low acquisition and running costs and
versatility of output.
As a consequence, the market for Bubble equipment is particularly buoyant. Users
look for a variety of attributes - in particular, the ability to work with sophisticated
shrink
wrap films and the ability for the machine to work consistently at a high
level of pack quality - this is a function of the design and build quality. One
should seek robust construction combined with good digital control features offering
a complete range of appropriate programme settings.
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