Keep the Ball Rolling
BMG’s Fluid Technology team has recently completed the design, supply and commissioning of an advanced lubrication system for a main bearing on a ball mill, which has been developed to optimise productivity and minimise maintenance requirements and downtime.
This specially designed circulating oil lubrication system was engineered to ensure the smooth operation and long-term reliability of the mill’s dual-pocket mill bearings and pinion bearings, providing both low-pressure oil conditioning and high-pressure lift oil circuits.
“BMG – which has designed and built lubrication systems for large-scale industrial projects for 50 years – developed this bespoke lubrication solution to ensure durability, efficiency and extended service life of the critical ball mill,” explains Taylor Black, Business Development Manager, Fluid Technology Projects, BMG. “This lubrication system supports two hydrostatic dual-pocket partial journal mill bearing assemblies (1,800 mm diameter and 420 mm width) along with two pinion bearings. All BMG lubrication systems comprise quality branded components to ensure adherence to stringent performance and safety specifications, to meet industry requirements.
“This circulating oil lubrication system includes a three-compartment reservoir, a low-pressure oil conditioning pump set, a high-pressure lift oil pump set, pressure relief valves and heaters. The system also comprises critical accessories and various instruments and safeguards to ensure optimal performance and reliability, even in harsh conditions.”
Key features of this lubrication system include a 1,700-litre capacity reservoir, equipped with inspection covers, a removable strainer basket, drip tray, drain, suction port, oil level gauges, an oil level transmitter, air breather and a structural steel base frame.
A low-pressure oil flow – in excess of 250 litres per minute (l/min), provides sufficient lubrication to the system’s components, while high-pressure oil flow is delivered to each of the four bearing recesses to support the hydrostatic bearings. Flow at 200 kPa is delivered to each of the two pinion bearings.
A duplex filter with 25-micron nominal cartridge-style elements is installed in the low-pressure line, equipped with differential pressure transmitters for monitoring. For dependable temperature control, a heater with a thermostat regulates oil temperature during startup or low-load operation. Temperature gauges and transmitters are installed at both the oil exit in the cooler and within the reservoir. High-pressure lines are fitted with pressure transmitters and gauges near the mill main bearing for precise control and monitoring. A water-to-oil plate and frame-type heat exchanger is used to dissipate heat. The system is designed to operate with ISO VG 320 grade oil.
Standby pumps for both low and high-pressure flows ensure continuous operation in case of a primary pump failure. These pumps are equipped with isolation valves and pressure relief valves to protect against overpressure conditions.
Skid-mounted flow transmitters for low-pressure lines and pressure gauges for high-pressure lines provide detailed real-time data on system performance. All field instruments using HART protocol, include local displays for ease of use. Silicone-filled gauges and calibrated field transmitters ensure accurate readings and reliable operation.
The BMG Fluid Technology team also designs and manufactures hydraulic power packs, bulk fuel filtration systems, grease systems, cylinders, manifold blocks and electrical panels. This equipment is supplied for various projects, including crushers, thickener drives, tailings applications, ball mills, filter presses, stacker reclaimers, fuel and oil filtration, furnace and winder applications, as well as load out stations.
