January 13 - Vanguard has completed the transportation from Walvis Bay and rigging into position of a cold box and exchanger for use in a smelting plant in Tsumeb, Namibia.
A modular trailer configuration was used which was 40 m long and featured a custom-made lightweight deck. "While the cold box was only 29 metres long and weighed approximately 50 tonnes, the added length on the trailer allowed us to correctly position it on the trailer in order to make manoeuvring on site easier. We were also able to transport the cold box on a continuous deck without the use of a turntable," says James Robinson, project engineer, Vanguard.
"The modularity and hydraulic suspension of the trailer worked to our advantage once on site because there were a number of obstacles to overcome."
Vanguard had to work around machinery and foundations on site, especially narrow foundation bolts that could not be driven over.
"Our modular trailer is extremely versatile and we basically mimicked a caterpillar in moving over the bolts. It was a slow and precise undertaking in which we would use the hydraulic suspension to lift one tyre at a time straddling the bolt, moving over it and then lowering the axle, in effect climbing over the bolts," says Robinson.
The trailers were then accurately steered into position, beneath gantry towers which Vanguard used in conjunction with its strand jacks to lift the cold box, and turn it 90 degrees into final position. "We transported and lifted the cold box first, then brought our gantry towers forward and rigged the 17 m long, 40 tonne exchanger into position."