Why Chemical Plants Specify Tungsten Carbide Bushings for Corrosive Media

Chemical plants operate in environments where pumps, mixers, compressors, and rotating equipment must handle highly corrosive fluids.

These conditions require components that can survive both chemical attack and mechanical wear.

For this reason, many chemical plants choose bagues en carbure de tungstène as their first option for shaft support and protection.

This article explains why tungsten carbide performs so well, which grades are best, and what decision-makers should look for when selecting bushings for corrosive media.

Why Corrosive Media Require Special Bushing Materials

Chemical processing involves acids, alkalis, solvents, chlorides, and aggressive mixtures that can destroy standard metallic bushings.

Bronze, steel, and even stainless steel can corrode quickly when exposed to these fluids.

Key problems with standard materials

Rapid corrosion that weakens the bushing
Pitting that traps chemicals and increases wear
Surface swelling that affects clearance and increases heat
Short service life, especially in pumps running 24/7
Higher maintenance cost due to frequent replacements

Tungsten carbide bushings solve these problems by providing both résistance à la corrosion and extreme hardness, a combination rare in metallic materials.

Chemical Resistance Properties of Tungsten Carbide

Tungsten carbide is a composite material made of WC grains and a metal binder. Its corrosion resistance depends mainly on the binder type.

1). Why tungsten carbide is résistant à la corrosion

WC grains are chemically stable
Nickel binders resist most acids and alkalis
The dense structure prevents fluid penetration
Faible porosité reduces chemical attack
Haut dureté protects against erosive-corrosive wear

2). Types of Corrosive Media Where TC Performs Well

Hydrochloric acid (HCl)
Sulfuric acid (H₂SO₄)
Seawater and brine
Chlorinated fluids
Caustic soda (NaOH)
Solvents
Wastewater with chemicals

Below is a comparison table showing typical corrosion behavior.

3). Corrosion Resistance Comparison Table

Matériel	Résistance à la corrosion	Résistance à l'usure	Best Application
Bronze	Faible	Faible	Non-corrosive fluids
Acier inoxydable	Moyen	Moyen	Light chemical exposure
WC-Co	Medium–High	Très élevé	Abrasive and semi-corrosive fluids
WC-Ni	Très élevé	Très élevé	Highly corrosive chemical media

Choosing the Best Tungsten Carbide Grade for Chemical Plants

Chemical plants typically specify two main tungsten carbide types depending on media and working conditions.

1). WC-Ni (Nickel Binder): The Best for Corrosive Media

Resists acid and chloride attack
Low cobalt leaching
Very low corrosion rate
Ideal for seawater, acidic wastewater, and strong chemicals

WC-Ni is the top choice for chemical pumps, mixers, and reactors.

2). WC-Co (Cobalt Binder): For Mixed Abrasive and Chemical Conditions

Plus fort dureté
Better for abrasive fluids
Suitable for slurry with chemicals
Not ideal for strong acids

3). Which grade is best for what condition?

Operating Condition	Niveau recommandé	Raison
Strong acids / chlorides	WC-Ni	Best corrosion resistance
Mixed abrasion + chemicals	WC-6Co	Haute résistance à l'usure
Sea water and brine	WC-Ni	Strong chloride resistance

Performance Benefits in Chemical Pumps

Chemical pumps rely heavily on shaft support and bearing stability. Tungsten carbide bushings improve system reliability in several ways.

Major performance advantages

Reduced shaft wear
Lower vibration
Better alignment stability
Improved pump efficiency
Longer running cycles
Less downtime due to bushing failure
Lower lifetime maintenance cost

Chemical companies often calculate ROI, and bagues en carbure de tungstène consistently provide better value over time.

Applications in Chemical Plants

Tungsten carbide bushings are used in various rotating equipment that must handle corrosive fluid streams.

1). Common equipment types

Pompes de procédés chimiques
Magnetic drive pumps
Agitators and mixers
Reactor circulation pumps
Seawater intake pumps
Acid-handling pumps
High-RPM dosing pumps

2). Common media handled

Hydrochloric acid
Sulfuric acid
Chlorinated solvents
Wastewater with chemicals
Sodium hydroxide
Brines and seawater

Wherever metal corrosion is a risk, tungsten carbide becomes the preferred material.

Failure Modes and How to Prevent Them

Even tungsten carbide can fail if conditions are extreme or incorrect grade is used.

1). Typical failure types

Binder leaching in strongly acidic media
Cracking due to misalignment
Abrasive wear from solid particles
Corrosion when cobalt binder reacts with chemicals

2). Prevention guidelines

Choose WC-Ni for corrosive media
Maintain shaft alignment
Ensure proper clearance
Control vibration
Use clean flushing or lubrication
Inspect early for micro-pits

Choosing the Right Supplier for Chemical Applications

Chemical plants need reliable suppliers who understand corrosive environments.

Supplier checklist

Experience with chemical pumps
Ability to supply WC-Ni and WC-Co grades
HIP sintering capability for high density
Strong QC: dureté, densité, microstructure
Full traceability and documentation
Ability to make custom designs
Fast lead time

Selecting the right supplier ensures long service life, stable performance, and reduced plant maintenance.

Conclusion

Chemical plants specify tungsten carbide bushings because they offer exceptional corrosion resistance, outstanding wear performance, and long service life in aggressive chemical environments.

By choosing the right grade, maintaining correct alignment, and working with a reliable supplier, plant operators can greatly reduce downtime and operating cost.

Si vous souhaitez en savoir plus sur une entreprise, n'hésitez pas à Contactez-nous.