Crane and hoist manufacturer Condra Cranes is manufacturing a 10 t, wide-span overhead crane – for ship chandling company Dolphin Offshore Chandling’s new maintenance workshop at the Port of Luanda, in Angola – in close cooperation with structural steel company Vlottenburg Engineering.

Condra’s crane for this workshop will be an electric overhead travelling machine with a span of almost 30 m, allowing for the full floor area to be serviced. The crane will work to maintain equipment brought in by Dolphin from oil exploration vessels and offshore oil and gas extraction platforms.

During the tender phase of the contract, Condra proposed that the crane lifting height be maximised to 9.1 m, almost the full height of the workshop walls, by designing girders with angled ends to match the slope of the workshop roof. Such a design allows for the crane to be mounted, with much of the machine’s volume occupying unused space within the roof.

There will be variable-speed drives on the hoist, and the long- and cross-travels, and control will be by pendant. Besides their angled ends, the 28.7 m-long twin girders have been

designed with splices to comply with regulatory restrictions on the road between Johannesburg and Luanda, where load lengths cannot exceed 18 m.

“Splice designs have become a common feature among Condra’s export orders. For the Dolphin Offshore Chandling crane, steel plates welded eccentrically to the four inside faces of the male box girder will result in a friction grip to reinforce girder strength and integrity beyond that delivered by the splice bolts alone.

“An internal box insert traversing the splice will deliver additional strength and rigidity, resulting in an almost seamless splice with a projected girder life in excess of 20 years,” the company states.

Cape Town subsidiary BB Cranes secured the Dolphin Offshore Chandling contract. Condra is executing the manufacturing at its Johannesburg works to reduce shipping costs. The order was placed in mid-August for delivery by the end of November.

Condra Cranes MD Marc Kleiner says the current steel shortage is compounding difficulties in the market, including the serious obstacle of declining service footprints to the efficient functioning of the subcontinent’s overhead crane market.

“Right now, we have an advantage because we have steel stocks, including essential square-bar. The steel supply situation for all manufacturers is likely to ease from November onwards,” he adds.

Service footprints beyond South Africa will remain a problem for most companies. However, Condra’s order book is benefiting, with the company continuing the on-time execution of orders at its factories in Johannesburg and Cape Town.

In recent months, Condra has captured an increasing share of the sub-Saharan market for cranes and hoists, with recent orders from Cameroon, the Democratic Republic of Congo, Angola, Botswana and Mozambique.

The company’s product lines of cranes, hoists and component subassemblies continue to enjoy a reputation for the lowest overall lifetime cost under harsh operating conditions, Kleiner says.