Why Water Quality Matters: Boosting Seal Reliability and ESG Performance in Heavy Industry

Why This Matters for ESG-Driven Industries

In industries such as mining and pulp and paper, water isn't just a utility—it's a critical component of production, maintenance and compliance. But when untreated or poorly filtered water is used in seal systems, it introduces a costly threat: premature mechanical seal failure.

As sustainability becomes a top priority across the industrial sector, ensuring water is used efficiently and safely has become essential for operational reliability and achieving ESG goals tied to water conservation, reduced waste and energy efficiency.

The Role of Water in Mechanical Seals

Mechanical seals and gland packing typically rely on water flushes to:

• Lubricate seal faces
• Cool rotating components
• Flush away harmful particles
• Quench volatile fluids

This water is often drawn from natural sources like rivers or oceans—bringing with it a variety of contaminants, including:

• Clay, silt and sand
• Organic matter (e.g., humic substances)
• Iron
• Scale-forming minerals (in hard water)

Seasonal changes, such as increased silt content during spring runoff, can exacerbate the issue—making consistent water quality challenging to maintain.

How Poor Water Quality Impacts Seal Reliability

Untreated or insufficiently filtered water contributes directly to mechanical seal degradation. According to John Crane's field reliability data, 59% of seal outages at sites using untreated water were caused by water quality issues.

Common failure modes include:

• Abrasive wear from particles >50µm damaging seal faces and components
• Blockages in seal piping, causing seals to run dry
• Scaling from hard water, increasing starting torque and mechanical wear
• Corrosion due to pH levels outside the safe operating range (6–8)

Each mechanical seal failure leads to unplanned downtime, increased water consumption and expensive pump repairs which can cost tens of thousands of dollars per event.

Water Quality Guidelines for Long-Term Seal Health

To protect seals and maintain uptime, recommended seal water properties include:

• Solids content: <10 mg/l
• Particle size: <50 µm
• Silicate content: <10 mg/l
• Permanganate number: <30 mg/l
• Iron content: <1 mg/l
• Water hardness: <10 °dH

Particles larger than 50µm are hazardous to mechanical seals and gland packing. While particles below 3µm are generally safe, anything in between requires careful monitoring and management.

Water Quality and Consumption: A Sustainability Concern

Poor water quality has a compounding effect:

• High particle loads require higher flow rates to prevent sedimentation — leading to excessive water use
• Sites without adequate treatment cannot recycle water effectively, increasing discharge volumes and treatment costs
• Each litre of water passing through a seal must be treated before and after use — doubling the environmental burden

Without the right water treatment strategy, operations can risk overspending on water, missing ESG benchmarks and dealing with more frequent failures.

What Comes Next: Solutions that Drive Impact

Part two of this article explores practical, field-proven solutions for improving seal water quality—without significant infrastructure changes. From compact inline filters like John Crane's SafeJet to advanced monitoring systems, these tools can help reduce water use, extend seal life and support your ESG goals.

If you're facing water quality challenges or looking to optimise seal reliability across your operations, John Crane experts are here to help. Reach out to discuss how we can support your plant's performance and sustainability targets.