Metso said its new Megaliner for grinding mill heads provides the same benefits as its original Megaliner, which was introduced in 2012: safe installation and maximized availability. The Metso Megaliner system for mill heads shrinks installation time because the liner has many fewer attachment points and the number of liner components is reduced by up to 80%.
Suitable for AG, SAG and ball mills, Megaliner for mill heads is larger than conventional liners, but light enough to allow handling by the same 7- to 8-axis liner handlers. Metso claims that Megaliner is also less prone to cracking than other lining types commonly found in this kind of application.
Megaliner for mill heads minimizes the number of components to be installed by integrating multiple lifter and shell plate rows and providing the option to include filling segments. Fewer installation points speed up the installation and change-out process. A reference installation of the Megaliner for mill heads on a 38-ft (11.6-m) AG mill resulted in a 30% reduction in installation time required, and according to Metso, there is potential for even further improvements.
Megaliner’s attachment system is designed to increase worker safety during installation and change-outs. There is no need for workers to be in the hazardous area near the liners because the liner bolts are attached from the outside of the mill. Metso’s Liner Positioning System allows the liner handler operator to act alone, maneuvering and positioning the liners without need for guidance from anyone inside the mill. Bright guiding markers make positioning and alignment even easier.
Removal is also safer and quicker, according to the company. The threaded portion of the standard hex-head liner bolt is protected from dust, corrosion and general mechanical damage. Once loosened, it is often possible to remove the liner bolts simply by hand-turning them. Pneumatic or recoilless hydraulic hammers are usually not needed for liner removal.