Extending rotating equipment life: How mechanical seal selection impacts mining efficiency
While every process has industry-specific challenges around the nature of the materials and the environments, mining and minerals extraction and processing demand more of the core equipment, specifically mechanical seals.
Processing abrasive and corrosive solids and slurries will cause equipment fatigue. Adding in the stresses of pressure fluctuations, which cause transient, vibrating waves to travel through the system, is another issue.
In addition, mining operations that manage slurries or abrasive materials often use a dedicated pressurised water supply to cool and lubricate packing or mechanical seals.
Meanwhile, fluctuations in slurry temperature cause repeated, alternating heating and cooling of pipes through seasonal changes, particularly in slurry transport and tailings management, introducing further mechanical and physical stresses that can affect seal integrity and maintenance costs.
Choosing the right mechanical seal
Seal selection is a key decision. The correct solution prevents premature equipment failure, increases uptime and minimises maintenance costs. Most importantly, the right mechanical seal delivering optimal performance will support wider equipment reliability and underpin process success.
For operators, the issue is selecting the correct sealing solution for their mining operation profile. Key factors include selecting the right abrasive-resistant materials for seal faces (silicon carbide or tungsten carbide) and the materials of construction for the seal itself. Elastomers must also be proven to withstand harsh chemicals and extreme temperatures.
Choosing the right combination of seal face technology, seal construction and elastomer bellows will extend equipment life by reducing wear on shafts and bearings, improving efficiency through lower friction and reduced energy consumption.
Preventing leaks of hazardous fluids used in heavy industry, characterised by chemicals such as cyanide, sodium cyanide, mercury and sulfuric acid used to extract precious metals, reduces environmental risk and protects people.
Complementary technologies
While the mechanical seal is the foundation of the system, other elements are also essential to create and maintain a successful sealing structure.
Couplings
Mining is a friction-heavy industry, and shaft misalignments are common. They cause vibrations and excessive loads on seals and bearings, leading to energy loss and premature failure.
High-quality couplings accommodate misalignment while minimising reactionary loads and transmitting torque between the drive system and driven equipment.
Misalignment that is not accommodated will cause higher vibration and excessive loading on seals and bearings, leading to premature failure and energy loss. By reducing vibration and accommodating misalignment, couplings improve power transmission efficiency and extend component life.
Crucially for the mining industry, John Crane’s Powerstream® couplings use an elastomeric element to transmit torque, manage vibration and accommodate misalignment on ANSI pumps, conveyors, rolls, fans and blowers. Operators can replace ours in minutes, reducing downtime.
Seal support systems
Mining and mineral extraction operations often take place in remote, harsh mining environments. Seals must perform at the edge of their operating capabilities, and operators can help extend equipment uptime by using seal support systems.
Barrier fluid systems or flush plans ensure seals operate under optimal conditions by controlling temperature, pressure and lubrication. Efficient support systems minimise energy waste and keep seals performing at peak efficiency.
Our barrier fluid reservoirs, heat exchangers and flush systems increase safety around critical pumps and hazardous fluids, and each solution complies with ASME VIII, ASME B31.3, AD2000, ATEX, CE, PED and SELO.
Diamond faces
Diamond-treated seal faces offer exceptional hardness and low friction. This reduces heat generation and wear in abrasive mining environments, lowering energy consumption and extending seal life. Less friction means that pump seals run more smoothly, improving overall system efficiency.
Created with industrial processes in mind, adding John Crane Diamond to mechanical seal faces helps overcome short seal life and equipment breakdowns caused by harsh operating conditions, including abrasive particles, low lubricity and intermittent dry running.
Upstream Pumping Systems (USP)
Consuming less water than a clean flush, John Crane’s unique, engineered, non-contacting USP seal face technology delivers clean, pressurised fluid to the seal faces, improving lubrication and cooling to reduce friction.
Preventing contamination from abrasive slurry is key to maintaining, which otherwise increases energy demand and wear. Better lubrication translates into lower power requirements and longer maintenance intervals while extending MTBR for traditional seals from three to more than five years.
John Crane Sense® Monitor
Even with the correct seal selection and support system, operating conditions will change, particularly in an industry working in volatile conditions. But remote locations can be difficult and dangerous to monitor manually.
John Crane Sense® Monitor is our wireless condition monitoring solution. It provides continuous, near real-time visibility into the health of rotating equipment. It can detect issues that directly impact seal performance, such as imbalance, misalignment, cavitation, bearing wear and shaft instability, which can accelerate seal face wear, increase leakage risk and shorten equipment life.
Predictive maintenance reduces unplanned downtime and protects critical mining assets. Identifying problems early enables corrective action, protecting both the sealing system and overall mining efficiency and, crucially, the safety of mining operators.
Mining operations: Three best practices for extending seal life
Firstly, choose a mechanical seal created for harsh conditions and abrasive materials. For example, the heavy-duty, Type 5860 series is compatible with advanced seal face technology, such as John Crane Diamond, while the Type 5864 USP uses Upstream Pumping for additional resistance.
Secondly, standardising seal technology across sites supports consistency, reduces complexity and, by simplifying maintenance and inventory, minimises maintenance downtime. The Type 5840 is a low-cost, single-cartridge seal compatible with most OEM slurry pumps worldwide and suitable for medium (50%) duty slurry environments.
Finally, boosting internal technical expertise through external expert training helps operators extract maximum value from technology infrastructure investments, while correct installation and inspection reduce downtime and accelerate issue resolution. Training, delivered locally at customer sites or at John Crane’s training facilities, is a key module within the wider John Crane Performance Plus™ modular service framework.
In short, the right seal technology is not an expense so much as an investment that pays off in reliability, efficiency and cost savings. With more than 100 years of sealing technology expertise, John Crane’s experts offer tailored sealing solutions for every mining situation.
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