How to transport float glass

In 1957, British company Pilkington developed the float glass process, a revolutionary method that fuelled the mass production of flat glass. Pilkington’s concept did not only supplant the Fourcault procedure, but also created a new, not-so-common freight task.

Float glass would now come in a standard size of 3.2m x 7m, but could go up to 3.2m x 10m with a thickness of up to 19mm – urging the world’s trailer manufacturing industry to invent a vast array of sophisticated transport equipment to cart the oversize, yet brittle commodity.

In the beginning, the transport scene used to modify the common rigid design by simply connecting a superstructure to the platform – usually a rugged, A-shaped framework. Later, a British company named Supertrucks re-fined the concept and introduced an external rack that could be attached to the side of a van, sparing internal load capacity.

Supertrucks presented the new concept at the Glassex exhibition in Birmingham in 1986 and the subsequent success established the company as a leading provider of glass carrying equipment in the UK and Ireland.
But, although the external rack is a versatile solution, the British concept is limited to 7.5 tonne GVM and cannot offer full protection against wind and weather, which may jeopardise the entire shipment.

After all, water is the nemesis of modern glass transportation. If only a few drops invade the gap between the panes, they will stick together inseparably – and the entire load will be useless.

On that account, so-called inside-loaders have become the standard equipment in Europe’s glass transport industry, surpassing the classic outside-rack design by providing effective moisture protection. But, the manufacturing industry tends to keep its knowledge close to the vest as the glass transport market is a profitable, yet competitive one. Nonetheless, Global Trailer presents a roundup of what appears to be emerging globally in this up-and-coming space.

German company Langenfeld, for instance, developed the Floatliner, a curtain-sided semi-trailer that can be lowered to the ground to take in the A- and L- shaped racks commonly used in the European glass industry.

The loading process is simple yet ingenious. Once the rear gate has been opened, the Flotaliner will reverse and take in the pre-loaded rack through the back, virtually merging frame and vehicle.

To fasten the glass on the rack, Langenfeld developed a hydraulically operated load restraint device named Hydro Push. It is based on either two or six horizontally arranged pads per side that hold the fragile freight in place. The systems can be mechanically adjusted in longitudinal direction to cater for varying load lengths. And, as an extension of the Hydro Push system, the Top Push configuration can also offer a vertical load restraint option.

But, every form of load restraint is obsolete if the humidity inside the compartment is not regulated to avoid condensation, the process of water vapour turning back into a liquid form. It usually occurs as a reaction to a sudden temperature change, cooling the ambient air to a point where mere thermal energy cannot separate the water molecules anymore. Such temperature fluctuations cannot only happen during the loading and unloading process, but also on the road, for example while passing through a tunnel.

Therefore, Langenfeld’s temperature-controlled Floatliner is force-ventilated and able to compensate unforeseen temperature drops. In addition, a breathable cotton tarpaulin under the roof is supposed to absorb excess humidity and a small roof spoiler prevents water from falling down on the sheets while unloading the vehicle.

Based on a box frame made of high-tensile steel, Langenfeld’s solution can boast a payload of 31 tonne. To extend the Floatliner’s load capacity, Langenfeld also developed a drop deck version, offering an additional compartment behind the prime mover to transport palletized goods or small containers. The extended version can host a sheet length of 8.1m as compared to 7.7m in the standard version. Both include a BPW axle/ air suspension combination and Wabco’s T-EBS as standard fitment.

To take in the rack, the Floatliner can be lowered up to a point where it is hovering 90 mm above the ground, and again be lifted up to a height of 450 mm when travelling on the road. To operate such a variable air suspension system, Langenfeld’s glass transport solution is equipped with an additional 100-litre air-tank to guarantee a safe loading process that is not dependent on a running engine.

Today, the German solution is in use all around Europe, but also in Brazil, Japan, China, USA and the Middle East. According to Langenfeld’s US affiliate, Loadlifter Solutions, North Africa is now starting to embrace the technology as well. Around the globe, around 3000 units are in use – and counting.

Meanwhile, Langenfeld’s Belgian rival, Faymonville, has introduced a similar model named Floatmax. Just like the Floatliner, it can be lifted vertically by crane to be loaded on a modern train carriage.

But, alternative concepts are now gaining ground, merging the in-loader’s pragmatism with the versatility of a curtain-sided solution and finally waving the old glass rack goodbye. After all, the classic in-loader can only transport standard glass frames, meaning that it must frequently return empty following delivery.

Therefore Van Huët Glass Logistics of Tiel in The Netherlands expects that the new MaXi-Trailer concept will be a major breakthrough in the glass industry, as it does not depend on the typical A-frame anymore.

Presented in 2008, Van Huët’s MaXi-Trailer can be converted from a glass transporter into a standard curtain-sider capable of accommodating up to 34 Euro-pallets. Van Huët managed to integrate a foldable platform that can either carry a rack or provide a flat surface if necessary. According to Van Huët, the new system can provide cost savings between 10 and 15 per cent compared to a classic in-loader. Just like Langenfeld’s Floatliner and Faymonville’s Floatmax, the Dutch alternative can also be transported via ship or rail. “Within five years there will be 250 MaXi-Trailers driving in Europe,” says Bert Strikkers, Managing Director of Van Huët.

In Canada, the curtain-sided solution is gaining ground as well. Local company Bromer Inc. offers a curtain-sided drop deck semi-trailer with in-built aluminium glass racks that are accessible from both side and back of the trailer. In addition, Bromer offers a 28-foot rigid version with an alternative option – the sides of the truck can be accessed from the exterior via aluminium folding doors.

Despite such progress, glass transportation still is an arguable issue. Some, like Chinese glass specialist Hui Hua Glass (HHG), ship float glass in a common marine container, secured in a wooden transport box, while still some prefer the external glass rack that debuted half a century ago.

US family company Schodorf Truck Body & Equipment, for instance, has designed a 24-foot glass transport truck body based on a heavy-duty aluminium frame that can combine both load capacity and easy accessibility. But, Schodorf’s solution, too, does not include full weather protection.

New Zealand-based The Glass Racking Company (GRC), therefore, developed a curtain-sided solution that can be loaded from above, merging Bromer’s concept with Schodorf’s easy-access philosophy.

In that sense, the curtains conceal the glass load and allow easy access to the external glass racks from the sides of the trailer, while the internal racks can be accessed through a glide top roof that can be pulled to the front of the trailer.

At the rear end, the trailer is equipped with a classic container-style door and a 3m slide-out ramp to allow easy access to the internal racks and load. GRC’s semi-trailer, which is used in Australia, New Zealand, USA, Canada and England, hovers 720mm above the ground to increase storage capacity and is based on air suspension to ensure a smooth ride.

Even designated industry experts cannot foresee which solution will dominate the future of glass transportation, but they agree that distance will remain a crucial factor. According to European trade association, Glass for Europe, transport costs make it uneconomic for float glass to travel long distances by land. “Typically, 200 km would be seen as the norm, and 600 km as the economic limit for most products, though this varies between markets.”

While the external rack solution is prone to dominate the short-distance market, the in-loader design may remain the first option to cover long distances – despite being challenged by a variety of curtain-sided alternatives that offer more versatility, but less moisture control.

Either way, global market data show that demand for float glass will remain high, especially in China. The People’s Republic is not only the largest consumer of glass in the world, accounting for 50 per cent of global demand in 2009, but also the largest producer, producing over 50 per cent of the global output of flat glass in 2009. It can boast the greatest number of glass producing enterprises and has the largest number of float-glass production lines in the world. Therefore, the future of modern glass transportation is likely to be decided in the Middle Kingdom.

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