Mill Liner Handlers and Cranes for the Mining Industry
McLellan, founded in 1965, is a San Francisco-based company that manufactures products for the mining industry, including a full line of grinding mill re-line equipment.
In 1970, McLellan designed the first mill liner handler and has been known as a leader in the mining industry ever since. Our off-highway support equipment includes heavy fuel lube trucks, water trucks, fuel trucks, combination fuel and lube trucks.
Electric / hydraulic powered mill liner handlers for mining operations
The McLellan mill liner handler is an electric / hydraulic-powered machine that is designed to assist in replacing the worn shell liners in ball and sag type grinding mills for processing ore from mining operations. The machine consists of a main frame with electric motor-driven hydraulic power, four-wheel drive and a main beam structure that extends inside the mill normally through the feed trunnion. The main beam is only supported by the main frame and includes a ‘liner dolly cart’ that moves new and used liners from the rear of the beam to the front end.
A telescoping crane is located on the front end of the beam that has three axis movements (up/down, swing left/right, and extend and retract). The crane with either the use of a load hook and sling or fixtures lifts the liner from the dolly cart and places on the inside shell of the mill while workers fasten with bolts. Some liner handlers have a hydraulic-operated ‘manipulator’ or ‘grapple’ that grips the liner and adds additional movement in placing liners.
Custom designed mill liner handlers
A wide variety of custom sizes are available to meet the vastly different mill types, sizes and facility designs. Each machine, while using standard components, is specifically designed to each mill by our team of design and application engineers. The main frame is constructed with structural steel tubing and plates to support the high loads experienced by the liner handler. The structure is checked with finite element analysis (FEA) engineering programs.
Four-wheel drive mill liner handlers
The McLellan exclusive 4×4 drive wheels allows four-wheel drive, plus four-wheel steer, which allows limitless manoeuvrability. The liner handler can drive forwards and reverse, move side to side and spin 360o. This makes positioning the machine up to the mill better than any machine on the market. Drive wheels are driven by hydraulic motors on all four wheels.
Hydraulic mill liner handlers
All McLellan liner handlers have a 227l or 378l reservoir and a 22kW or 30kW electric motor-driven hydraulic pump. The hydraulic pump is a pressure compensating pump that allows maximum flow only when needed by selected functions. All hydraulic hoses are wire reinforced with swaged fittings and are protected by a stainless-steel hose track assembly, which allows easy maintenance.
Standard controls include direct connected proportional hydraulic control valves. McLellan offers proportional electro-hydraulic as well as wireless radio proportional controls. All controls allow a finite metering of hydraulic functions.
Hydraulic-driven cranes for mining applications
Cranes are heavy-duty box beam constructions that are either two or three-stage telescopic. Rotation uses a main rotation bearing, rotary manifold for continuous rotation, worm drive hydraulic-driven heavy-duty gear box with an integral clutch to prevent damage to rotation system from improper side loads. All cranes include a removable load hook plate.