Twiflex is a leading global supplier of power transition components and has been working to provide parking brakes that will be used on mine hoists at Nkana’s Mopani Copper Mines in Zambia. Nkana is known for being one of the largest copper and cobalt mines in Africa and operates four underground mines as well as an open pit.
FLSmidth, the leading mine hoist manufacturer has worked with Twiflex and their South African distribution partner, Tritec Sintered Products in order to carry out the installation of the new parking brakes. FLSmidth supplied the project with a double drum Blair Multi-Rope rock winder and a single drum BMR as well as man/materials winder to the Nkana project.
The BMR winder has been developed as a variation on the double drum winder and can be used in extremely deep shafts with the second drum on the winder used to balance the primary load. The drums installed to both winders are identical and measure 5.7 meters in diameter with a rope compartment that is 1.8 meters wide.
Twiflex brakes are used as part of the copper mine hoist for parking and holding each time the mine winders stop. If anything untoward happened like, for example a power failure the brakes can be used to bring the load to rest while maintaining a maximum deceleration of 2.3 m/s2 Twiflex engineers also worked to design the new large pad version of their popular VMS3-SPS spring applied, hydraulically-released brake that is used on a range of different hoists around the world. Twiflex is able to utilise their in-house testing capability, which includes a climatic chamber, in order to test the brake systems for functionality in a range of temperatures as well as fatigue and inertia. For brake manufacturers friction material needs to be carefully selected to be suitable for the operating cycle.