The wagons will be carrying coal from the coke mine to the port of Beira.

The 98 wagons and two containers of spare parts were railed about 23km from TRE’s wagon business at Uitenhage to the Port Elizabeth harbour, South Africa.

From there they will be shipped to Mozambique.

The first 102 wagons were delivered in December.

TRE sourced 85% of the materials and components for the wagons in South Africa, with only the draw-gear and a few specialised components being imported.

Each of the Tippler coal wagons weigh 21.5 tonnes and have a 71 cubic metre carrying capacity.

It translates to a 61.5t coal payload.

Coal contains sulfur, which forms a weak acid when leached out by rain or the water used to suppress coal dust.

To combat this, TRE manufactured the load boxes from corrosion and abrasion-resistant 3CR12 steel.

The load boxes have eight drain holes in their floors to ensure water does not accumulate.

Because the axle load limit on the Sena line the wagons would be using was limited, weight saving was a priority.

The side sills have been box-fabricated to save eight and also maximise the vehicle width within the gauge restrictions, while also maximising support for the pusher pads.

TRE also used finite element analysis software to trim about 1.6t from the wagons.

The wagons have both F-type rotary and non-rotary couplers to allow for tippler offloading when the port of Beira ultimately has car dumpers installed.

The wagons are fitted with TRE’s self-steering bogies, which are designed to reduce rolling resistance – particularly on curves.

The company claims at least 50% higher speed for wagons fitted with these bogies due to their greater stability.

TRE group chief executive Brian Molefe said the company would be sending staff to train and supervise the Mozambican workers responsible for maintaining the wagons.