Shrink or stretch?
Page 18
Page 19
If you've noticed an error in this article please click here to report it so we can fix it.
NINETEEN EIGHTY-TWO should be a contender for the title "International Shrink and Stretch Wrap Year".
For at last week's 1982 Unit Load Show at Wembley, of the 110-plus manufacturers exhibiting, over 40 were displaying either shrink or stretch pallet wrapping equipment or associated pallet covers and film.
Show organiser Gordon Carlton said that the first Unit Load Show, in 1976, had been dominated by the good old timber pallet while the pallet-based container was the star of the second show in 1979.
Although pallets and their many derivatives were still much in evidence this year, the emphasis on shrink and stretch wrapping for palletised loads reflects the trend towards higher standards of load protection. In much the same way as curtainsiders are partially replacing flat bodies, so shrink or stretch wrapping can replace conventional strapping around palletised loads.
Both techniques offer better weather protection, minimise pilferage and avoid crushed cases caused by overnight strapping. Judged purely on the number of exhibitors stretch wrapping seemed to be slightly more popular than shrinking.
Typical of the stretch wrapping machines was a new one from C. J. Hall (Witney), which wraps the pallet load from the base upwards with a continuous spiralling band of stretch wrap film. The pallet (which can weigh up to 1.25 tonnes) is turned on an electric turntable while the film roll automatically rises to spiral wrap the load.
W. T. Atkin of Thetford claims that its new stretch wrapping machine is a breakthrough because it uses a full-width roll of film up to 1,900mrn (6ft 3in) wide to wrap a pallet load up to 1,800mm (5ft 11in) high in just one or two revolutions. This takes just 45 seconds for two revolutions and is neater than using a spirally bound narrower film. The machine is also available with a top roll dispenser to seal the top of the load (normally left open in stretch wrapping) and with a turntable adapter to wrap roll cages. The basic machine costs £3,750.
The main advantage claimed by the advocates of shrink wrapping is that it needs no costly wrapping machine. Instead, a large polyethylene pallet cover is thrown over the load and heat is applied to the cover so that it shrinks and grips the load, giving strong all-over protection including coverage of the top.
Although it is initially cheaper, shrink wrapping using a handheld heat gun is slow (it takes about two minutes per pallet). Among the exhibitors of shrink wrap pallet covers was Trioplastic Packaging of London N20 which also markets the Ripack heat gun. Like the other heat guns that are available it operates from a bottle of propane gas and is fitted with piezo-electric ignition. Price is £299.
A neat way of overcoming the slowness of shrink wrapping was demonstrated by West German manufacturer Ahrendt & Birkendahl of Wegberg. It consists of a trolley containing two propane gas bottles and a verti cal stack of eight burners. The operator merely wheels the trolley around the pallet load and can shrink the entire cover with one movement in about 40 seconds. It costs £2,500.
An even more advanced model by the same manufacturer uses a stationary tower of eight burners and it is the pallet that rotates on an electric turntable. This model costs £6,500. Ahrendt & Birkendahl was hoping to appoint an English distributor during the show.
Another way of keeping cases stacked neatly on a pallet without strapping (although without the added protection of stretch and shrink wrapping) is to use some form of adhesive between the cases. On-line systems of 'coating cases are available but Lawtons of Liverpool was showing an aerosol of Lawco Spray Bond multi-purpose adhesive which can fulfil the same function on a smaller scale. Ten aerosols cost £44.85.
Despite many further developments of it, the humble timber pallet was still very much in evidence. Among the exhibitors were three leading UK timber pallet manufacturers, Tilgate Pallets of Crawley, Unit Pallets of Warrington and W. H.. Shaw of Oldham. Timber pallet manufacturers have gone through a thin time in the last year or so, but recent signs are encouraging.
For instance, production at Unit Pallets had fallen to 25,000 a week but is now up to 35,000. The 1,000x1,200mm timber pallet is still the most popular size, accounting for an estimated 6070 per cent of the market. Prices have dropped recently and a good quality 1,000x1,200mm four-way entry timber pallet now costs £4-£4.50.
The timber pallet has spawned a whole range of imitators and examples of steel, plastic and disposable corrugated board versions were on show.
A German design of galvanised pressed steel pallet called the Nestel was displayed by Shrewsbury Tool and Die Company; it was launched in this country last September. The Nestel pallet is available in 1,000x 1,200mm and 800x1,200mm sizes and costs around £20. It weighs slightly less than the timber equivalent.
Typical of the plastic pallets on offer were those by GPG of Dunstable. This company produces a range of plastic pallets in standard sizes, all with the advantage of being very light (613kg) and available in different colours so that a colour coding system can be used in the warehouse.
Because they do not rot or rust, plastic pallets are claimed to be the most hygienic type and so have made most progress in the food industry. Like steel pallets they are initially more expensive than timber (about £17 for a 1,000 x 1,200mm) but should last well.
At the opposite end of the pallet market are the corrugated board disposable pallets such as the Interpal made by Bowfort, a division of Bowater Containers of Manchester. Made in recognised pallet sizes they have a simple, flat board deck with polypropylene feet. They are light (3kg), nest very compactly indeed and if the load is evenly distributed can bear up to one tonne.
Because of their low weight and low cost, disposable pallets are ideal for air freight and export where you do not expect to see the empty pallet again. The Interpal is priced at around £2.30 and part of system whereby a flange can be added to make a shallow tray and a heavy-duty board box added to make a disposable pallet box.
Tillotsons of Cambridge was displaying its range of Pal-Box corrugated board pallet boxes which incorporate a built-in pallet base using polystyrene feet. Being very light (6-12kg, depending on size) they are once again suitable for export/air freight. The most popular size is the 1/2 Europa (0.3cum) which costs £10.41 each, with bulk discount available.
A new corrugated board pallet box launched at the show was on the stand of Phoenix Pallet Cases of Halstead. Unlike the others in the range which use polystyrene feet this new model has a lightweight timber base to increase its weight capacity.