A three hour journey from the vessel in the Coega port to the new R300 million Afrox plant within the Coega Industrial Zone (IDZ) carrying a 100-tonne 38-metre ‘cold’ box’ was recently undertaken by Vanguard.

The cold box is an insulated enclosure containing cryogenic heat exchangers, distillation columns and associated valves and piping.

Roland Cumings, managing engineer at Vanguard, said, “The trailer configuration is mainly governed by the route to our destination and the mass and geometry of the load. By virtue of being self-propelled, the trailer allowed an over-hang on the front and back, so we were able to reduce the length of the trailer thereby tightening up the turning radius.”

This ensured that the trailer could negotiate the road corners and the access to site without making changes to any infrastructure. While the distance from the port to site was limited, the route was within the Coega IDZ and strict authorisations were required from the Coega Development Corporation to preserve civil works.

Adding, “The IDZ permits are even stricter than national and regional roads, involving the submission of traffic management plans, risk assessments and engineering reports. We engineered this particular solution for our client in order to reduce the risk and cost of making changes to IDZ infrastructure.”

Positioned on staging beams on the PST, the cold box could then be staged on stands at the Afrox site while the trailer was hydraulically lowered and driven out.

The second phase of Vanguard’s contract was to move another shipment of Afrox plant, this time comprising four large tanks – three for nitrogen and one for oxygen – each weighing about 100 tonnes and measuring almost 30 meters in length.

“These were more technical moves, requiring long trailers and dealing with some challenging constraints such as very tight clearances between the large diameter tanks and the bridges and portal sign we had to pass under. There were at times less than two inches of clearance after activating the hydraulic lowering functions on the trailer.”