The steel specialist VR Steel Ltd. with its headquarters in Alrode South Africa, offers, among other things, shovels for scraper excavators in their wide range of products. These very heavy machines are put to use in surface mining mostly in South Africa, the USA and Australia. On the company’s production site the shovels that are the size of a lorry, are overhauled and also produced. With the help of cranes the VR Steel employees can move the oversize parts during production.

Pro Crane Services, an independent crane building company from Johannesburg, has been charged by VR Steel with planning and constructing the necessary cranes. As A partner of hoisting specialist SWF Krantechnik GmbH for the South African area, Pro Crane Services has designed seven cranes together with the Mannheim based company so far. They are all specially designed for the customers needs and each is equipped with the NOVA heavy duty electric wire rope hoists. The components such as travelling motors, end carriages, electric control system, power supply etc. were delivered by SWF – Pro Crane Service took over the planning, the steelwork and the installation.

The most recent crane was specially designed for the handling of the gigantic excavator shovels. A durable double girder crane system ensures an ultimate load of 80 tonnes for the 19,7 meter long crane bridge. Two double girder trolleys NOVA with 80 tonnes ultimate load each and a hoisting height of 10,4 meters, provide for save handling of the shovels. The two hoists are also used for moving the parts e.g. when working on the lower side of the excavator shovels. In addition to this one of the two hoists is also equipped with an extra 10 tonne NOVA hoisting motor for moving lighter parts into position. The two-step hoisting speed of the 10 tonne hoist is 5 /0, 83 m/min.

Next to the standard frequency inverter control for stepless and therefore soft moving of the load for trolley and crane drive, VR Steel also ordered the electric hoist monitoring system NovaMaster. With its help the hoists are continually monitored and, for example, protected against overloads. The crane driver can read all the hoist’s relevant data such as current load on hook or remaining safe working period directly on the control switch on a LCD display. This contributes to the safe operating of the crane.

NovaMaster also makes it possible to connect the two hoists for tandem processing via CAN bus function. In addition, NovaMaster protects the mechanical parts and the hoisting motor brakes because of the load’s soft lifting and stopping. Stopping and accelerating always happen automatically in the lower hoisting speed by which the hoisting motor brake is spared. Wearing and resulting maintenance costs are reduced. Cost intensive standstill times are reduced through a longer lifetime of the single hoisting components.

In this special case, there is a Pro Crane Services service point very near the crane, which will guarantee for even shorter standstill times in case of maintenance or repair works.

Within three days a team from Pro Crane Services managing director Rob Williams could install the crane and hand it over to the operator. On the same crane runway there is also a double girder crane with an ultimate load of 30 tonnes – also from Pro Crane Services and SWF Krantechnik.