Kahl carries 535t transformer

26 April 2018

A giant transformer moved through the streets of a German city, carried by a Goldhofer high girder bridge

Just before 22:00 on January 24, Andre Krause, project manager at the Kahl Group, gave the go-ahead and a huge heavy-haulage operation began.

Onlookers watched as a Siemens 1100KV UHVDC transformer, with a deadweight of 535t, began its journey from Siemen’s Nuremburg fabrication plant to the city’s port.

It was carried on Kahl’s G2 I K600 high girder bridge, made by Goldhofer and Greiner, coupled between two Goldhofer modules: a THP/ST 10 P (1+1) at the front and a PST/SL-E 10 P (1+1) at the rear.

The high girder bridge has been designed for a maximum configuration of 2 x 24 axle lines and a maximum payload of 600t. The total weight, including the carriers, was 875t.

The K600 bridge, the first one produced by Goldhofer, was acquired by Kahl in 2015 and has since been used to fulfil several contracts. Its payload to deadweight ratio of 5:1 helps reduce axle loads when transporting extremely heavy cargos—important here since there were load restrictions as well as height restrictions on the route.

In the early planning stages of the project the specialists at Kahl realized that the operation was going to be an extremely large one in terms of weight. With a length of 63m, a width of 7.45m and a height of 6.10m the laden rig weighed 875t. “With Goldhofer’s heavyduty and self-propelled modules coupled in parallel we were able to minimize the overall length of the combination so as to guarantee the maneuverability we needed for the critical passages, like the underpass under the Minerva Bridge in Nuremberg”, said Krause.

To prepare for the journey Krause relied on Goldhofer’s dedicated easyTRACK and easyLOAD software to ensure optimum positioning of the cargo with regard to weight distribution and centre of gravity and to simulate the itinerary as realistically as possible. However, computer simulation can only reproduce reality to a limited extent, which is something that Krause and his team discovered right at the beginning of the journey. The cargo had been secured in the high girder bridge with more than 30 chains and the rig had just started to move when, just outside the exit from the Siemens plant, an unforeseeable obstacle was discovered. An incorrectly parked truck left so little space to pass that the journey seemed over before it had begun. But a tow truck quickly arrived and lifted a vehicle parked on the other side of the road out of the way so that, although narrower than originally calculated, there was enough space for the rig to pass.

With that slight delay but no other incidents or obstacles, the colossal rig rolled through the night and reached the port of Nuremberg the following morning.

“Once again the months of preparation paid off,” said Krause in praise of his team. “Of course the occasional adjustment had to be made on a couple of bends, but without the illegally parked truck we would have arrived right on schedule.”

After an operation lasting just under 20 hours the rig reached the port of Nuremberg. There the transformer was quickly loaded onto a barge to be taken to Antwerp, where its 3300km journey to China continued by sea. “This mega transport operation was a successful premiere for us,” said Krause. For there are similar moves on the way. “We have another three of these giant cargos coming up for the power generating industry. I was particularly impressed once again by the G2 I K600 high girder bridge, which we have already used for a lot of challenging operations on national and international routes. I am proud that we are able to handle such demanding jobs.