How a high-torque drivetrain, optimised tooth configurations, and tungsten carbide extend capacity and lifespan in crushing applications.
Mining technology manufacturer TAKRAF has recently seen a significant order from Rio Tinto for six of its X-Treme Class Sizer machines for the Simandou Iron Ore Complex in Guinea. These machines are currently being manufactured at TAKRAF’s Product & Service Centre
in Germany.
In another important development, a new overlay solution has been incorporated into the sizer, providing protection of the base material from wear, resulting in an increased lifetime of wear parts. Known as TAKRAF Wolfram Armor, the tungsten carbide overlay was developed in-house over a five-year period to provide the sizing teeth with a combination of hardness and ductility as compared with other overlay types. The high level of hardness protects the sizer teeth from ‘washing’ abrasion caused by free-flowing feed material as the ductility of the base matrix provides protection from impact gouging and flaking.
To obtain the optimal level of protection from the overlay, TAKRAF works with clients to measure wear rates and patterns on equipment start-up. With this feedback, TAKRAF can revisit the design and optimise the placement and thickness of the Wolfram Armor. As a result, clients have been able to achieve OPEX savings of over 25%.
New generation of sizing technology
The TAKRAF X-Treme Class Sizer was developed as a new generation of sizing technology to extend the application window of a sizer into harder and more abrasive feed material. The fundamental design philosophy is to maximise the machine’s grip on large lumps. This is achieved by incorporating primary and secondary teeth, crushing ridges, and tooth pockets that let the lumps drop deep between the rolls where the engagement with the rock can be as aggressive as possible. By maximising grip, the sizer can process oversized feed material and eliminate high wear events where lumps remain, bouncing on top of the rolls for extended periods of time.
For extra-large feed sizes, classified as a feed exceeding 1,500mm, the TCS-X 18 series (TAKRAF’s largest sizer) can be equipped with the patented rhomboid tooth configuration, providing a larger pocket for oversized lumps to fall into.
Other features that aim to ensure extended reliability and increased availability when working on extreme applications include integrally cast tooth holders and shrink fit keys that transmit the high crushing forces required to break hard rock lumps. The machine’s heavy-duty bearing assemblies are sealed with a triple labyrinth taconite seal for bearing reliability, while the gearbox is designed with high application factors to produce the required torque and withstand shock loads from uncrushable material.
The machine’s modular wear components are easy to handle, according to the company, with change-out procedures actionable in position. The entire unit slides into its maintenance position for safe and efficient maintenance, with quick-release crushing segments enabling the efficient replacement of individual parts. The bolted tooth system means worn teeth can be replaced quickly while the split housing design enables the easy replacement of entire roll assemblies.
By extending the application window of a traditional sizer into hard rock applications, TAKRAF believes that many more mining operations will benefit from incorporating a sizer into their crushing applications.
