A new mining development in the Northern Cape received three new cranes as part of a six-crane order from Johannesburg-based manufacturer Condra.
The remaining three cranes are in the design phase. Condra will also manufacture four hoists and miscellaneous spreader beams for the mine.
The first two cranes delivered were 10 t single-girder electric overhead-travelling units ordered by the main structural steelwork contractor for the concentrator plant.
Condra’s affiliate company, Transcon Hauliers, supplied steerable dollies for transport to site, and also oversaw delivery and installation.
The third crane, which underwent testing, and was delivered at the end of 2017, is a bigger, 40/8 t dual-hoist double-girder electric overhead-travelling machine with a span of 23 m. It will be used for mill plant maintenance.
The first three cranes were manufactured on short lead times of 90 days, and were manufactured to blanket technical specifications and quality-control procedures stipulated by the mine developer. This allows for the first two machines to be handed over to the mine for future use after the structural steelwork has been completed and the contractor has left the site.
However, Condra MD Marc Kleiner notes that stringent quality control procedures made the short lead times a challenge. “Hold points at various stages of manufacture allowed for layout inspections, magnetic particle inspections, and ultrasound and X-ray inspections,” he says, adding that there were also assembly inspections, blast profile inspections ahead of painting, and a final, dry film thickness inspection after the painting of each crane had been completed.
Kleiner says production was halted at each of these hold points, which made it difficult to meet the lead times, “but, nevertheless we completed all three cranes on schedule”.
Although the six cranes are for different companies working on the development, industry observers point to a common thread of robust design and proven machine reliability as being the key to Condra’s successful bids.
In terms of the company’s design capability, Kleiner highlights that the design team submitted a selection of designs from which the steelwork contractor could choose. The single-girder option on the 10 t model was found to deliver an ideal combination of capacity, lift height and speed, while the larger size of the 40/8 t crane necessitated a double-girder design, he says.
Condra routinely executes design, manufacture, delivery, installation, commissioning, servicing, load testing and certification as a turnkey offering to customers worldwide, using a fully developed logistics network.
The company claims a parts delivery time of just 24 h anywhere in South Africa and a maximum of 72 h to all countries within the Southern African Development Community, except the Democratic Republic of Congo, where customs procedures can delay delivery time.
Condra is also eyeing expansion in the Western European market, although Kleiner says this is taking longer than expected because of strong resistance by crane manufacturers based there.