When pumping slurry, gland seals can be prone to leakage. This is often caused by inadequate maintenance, incorrect lubrication application, poor quality gland water, or a combination of all three. Plant operators should be vigilant against gland seal leakage as it can cause premature bearing assembly failures, leading to downtime.
Inadequate gland maintenance can cause leakage, spraying slurry or water directly onto the pump’s bearing assembly. If this penetrates the bearings, there is a high risk of failure.
In some instances, incorrect gland seal adjustment causes unwanted leakage. This can be resolved by regularly adjusting the seal and ensuring seal water supply is high quality and free of abrasive particles.
Bearing assembly lubrication
In addition to contamination ingress from leaking gland seals, Incorrect bearing assembly lubrication volume is another factor to be mindful of. If a pump bearing assembly is over greased, a build-up of excess grease in the bearing assembly cavity can cause grease churning resulting in elevated bearing temperatures. This leads to rapid degradation of grease and subsequent bearing failure. Conversely, if the bearing assembly is under greased, the loss of fluid film lubrication will cause premature bearing wear. When this occurs, the remaining grease will experience accelerated degradation due to internal contamination caused by abrasive wear particles.
To help prevent premature bearing assembly failures, Weir Minerals recommends that grease should be regularly supplied to the bearing assembly labyrinth seals using Warman® Accumin® automatic lubricators. This provides a protective barrier against gland leakage and other sources of external contamination whilst also regreasing the bearings.
Michael Roinich, Weir Minerals Accumin® Product Specialist states “Our Warman Accumin automatic lubricators are a heavy-duty, single point lubrication system designed specifically for Warman slurry pumps. They deliver the required amount of grease in line with our specifications and are fitted as standard on any new pumps. This helps our customers prevent bearing failures, keeping their operations running smoothly.”
The Accumin® range is comprised of two lubricators with easy to adjust dispensing systems. The Accumin® 125 lubricator, ideal for smaller pumps, is waterproof, gas operated and ready to use straight out of the box. The 250 model embraces the latest technology and is recommended for larger pumps, featuring a reusable electro-mechanical drive unit embedded with software which can determine fault codes. This model features an LCD display and LED indicators which immediately confirm the lubrication system’s operational status. Accumin® lubricators are suitable for most grease lubricated rotating equipment including conveyors, fans, electric motors, valves, filter belts, vacuum pumps, mechanical seals and gearbox seals.
Accumin® lubricators maintain a grease barrier within the labyrinth seal. This prevents external contamination ingress into the bearings from gland water or slurry.
Using Accumin® lubricators decreases the risk of lubrication related failures and extends the life of the pump. Accumin® lubricators deliver small amounts of grease at regular intervals for a seal purging effect. This allows any contaminated grease to be pushed out before it can further penetrate the bearing assembly. This is preferable to using a manual grease gun to insert a large amount of grease at once, which can result in over greasing and elevated bearing temperatures. The grease dispensing rate, in monthly increments, ranges from one to twelve months, allowing equipment to be lubricated as needed.
Furthermore, when compared to multi-point systems, single-point lubricators require less maintenance and are more economical while providing the same benefits.
“Our Accumin lubricators are part of our holistic approach to supporting customers, with the product designed to reduce bearing assembly failure for lower total ownership costs. We are the only manufacturer to provide a heavy-duty lubrication as standard on our pumps, helping our customers get the most out of their equipment,” states Michael Roinich, Weir Minerals Accumin® Product Specialist.
Adopting a proactive approach to pump maintenance and lubrication will help improve equipment reliability and its lifespan, whilst reducing maintenance costs and downtime.