Company Announcement - Condra has delivered the first two of eight double-girder overhead travelling cranes ordered by Veolia Water for the Lower Thukela Bulk Water Supply Scheme. The eight machines are maintenance cranes for the project’s high-lift and low-lift pump stations, and for the water treatment works’ decanter centrifuge, chlorine tanks, machine room, chemical doser and offloading bay.
All machines were corrosion-proofed using a hot metal zinc coating applied as a spray. The bulk water supply scheme under construction on the Tugela River is an Umgeni Water project, and comprises an abstraction works and low-lift pump station, a de-silting works, water treatment works and a high-lift pump station linked to bulk supply pipelines with associated water storage reservoirs. After completion early next year, the project will supply potable water from the Tugela to a number of towns along the KwaZulu-Natal north coast, from Mandini in the north to Ballito in the south.
Veolia Water’s order for the overhead cranes was worth a little under R5,5-million to Germiston-based Condra, which completed manufacture in January, holding the machines in storage until they were needed on site. The order builds on Condra’s long standing tradition of partnering with efforts to conserve and properly manage southern Africa’s water resources, with the company becoming one of the region’s preferred suppliers of cranes to water storage and wastewater treatment projects. Major orders have included cranes for the Lesotho Highlands Water Project, for which Condra designed and manufactured machines with extreme lift heights of up to 158 metres and, more recently, cranes for the Department of Water and Sanitation’s De Hoop Dam on the Steelpoort River in Limpopo Province, commissioned last year.
The De Hoop Dam’s main crane was built as a 40-ton machine with two auxiliary hoists of 5 tons and 2 tons. It works ‘blind’ under water, lifting and lowering screens and sluice gates, and placing and removing stoplogs, controlled by advanced technology that reads out the hook’s location accurate to within two millimetres as it is lowered down a guide shaft to the target gate or fine screen, while encoders take into account rope stretch as the rope unwinds during hook descent.
A load indicator tells the operator when the hook has successfully engaged the load, while hunting tooth limit switches help to control top, bottom and side travel so that positioning is kept as accurate as possible.
Condra is South Africa’s only multinational crane manufacturer, with headquarters in Germiston, Gauteng, and a factory in Bulgaria. There is an established worldwide distribution network.