Tungsten Carbide Bushings for Desalination and Seawater Intake Pumps

Desalination plants and seawater intake stations operate in some of the toughest environments in the world.

Pumps in these systems must handle constant exposure to seawater, sand, silt, and corrosive ions. To keep these pumps running reliably, many engineers choose tungsten carbide bushings.

This article explains why tungsten carbide is widely used in desalination, what grades work best, how it handles seawater corrosion, and what OEMs and plant operators should look for when selecting bushings.

Why Seawater Pumps Need High-Performance Bushings

Desalination systems and seawater intake lines run at high load, high flow, and long operating hours. Pump bushings must survive:

Continuous saltwater exposure
Sand and silt abrasion
High rotational speed
Corrosion from chloride ions
Vibration and misalignment
Start-stop cycles

Traditional materials like bronze or stainless steel often fail early because seawater is aggressive. It contains:

Chlorides, which attack metals
Sand and debris, causing abrasive wear
Microorganisms, leading to bio-corrosion
High dissolved oxygen, accelerating pitting

Tungsten carbide bushings solve these challenges because they combine Resistencia a la corrosión, abrasion resistance, and high hardness.

Key Performance Benefits of Tungsten Carbide in Seawater Systems

Tungsten carbide bushings offer unique advantages in desalination plants and seawater intake pumps.

Main benefits

Extremo resistencia al desgaste against sand, silt, and solids
Fuerte Resistencia a la corrosión, especially with nickel binder grades
Dimensional stability even under temperature changes
Long operating life, reducing pump downtime
Lower maintenance cost for operators
High compressive strength, preventing deformation

These benefits are essential for seawater systems where pumps run 24/7.

WC-Ni vs WC-Co: Choosing the Right Binder for Seawater

The binder type used in tungsten carbide bushings determines how well they resist seawater corrosion.

Desalination plants typically choose between WC-Ni and WC-Co.

1). Binder Comparison Table

Tipo de carpeta	Resistencia a la corrosión	Resistencia al desgaste	Recommended Application
WC-Co (Cobalt Binder)	Medio	Muy alto	Abrasive water with low corrosion
WC-Ni (Nickel Binder)	Muy alto	Muy alto	Seawater, brine, desalination plants

2). Why WC-Ni is preferred for desalination

Nickel resists chloride attack
Very low corrosion rate
Less binder leaching
Best choice for RO (Reverse Osmosis) and MSF (Multi-Stage Flash) plants

WC-Co is still useful where abrasion is severe, but corrosion risk must be evaluated.

How Tungsten Carbide Handles Saltwater Corrosion

Seawater corrosion is mainly caused by chloride ions, which attack metals and weaken them over time.

Tungsten carbide offers strong protection because:

WC grains are chemically inert
Nickel binder forms a more stable passive layer
Dense microstructure blocks water penetration
Bajo porosidad prevents pitting
High hardness protects against erosive wear

1). Corrosion Behavior Table

Material	Pitting Resistance	Chloride Resistance	Expected Lifespan
Stainless Steel 316	Medio	Medio	6–18 meses
Duplex Steel	Alto	Alto	12–36 months
WC-Co	Alto	Alto	3–5 years
WC-Ni	Muy alto	Muy alto	5–10 years

Where Tungsten Carbide Bushings Are Used in Desalination Plants

Desalination systems use several types of pumps. Tungsten carbide bushings are installed in:

1). Desalination pump types

High-pressure RO pumps
Booster pumps
Vertical sump seawater intake pumps
Brine recirculation pumps
Energy recovery pumps
Intake lift pumps
Pretreatment stage pumps

2). Functional roles of bushings

Shaft support
Reducing vibration
Preventing shaft run-out
Maintaining alignment
Minimizing wear on rotating parts

In all these roles, tungsten carbide provides long-term stability even with constant seawater exposure.

Common Failure Modes in Seawater Conditions

Even with strong materials, seawater can still cause failures.

1). Typical failure types

Binder leaching, especially in cobalt grades
Abrasive wear from sand and shells
Pitting corrosion when porosidad is high
Misalignment wear from pump vibration
Thermal shock cracking during rapid temperature changes

2). Simple ways to prevent failure

Choose WC-Ni for seawater
Ensure proper filtration to reduce sand
Maintain shaft alignment
Use high-densidad, HIP-sintered carbide
Inspect bushings during pump overhauls

Proper selection and maintenance can extend service life by years.

How to Choose the Right Supplier for Seawater Applications

Choosing the right supplier is critical for seawater pump reliability.

Important supplier capabilities

Experience in desalination industry
Ability to supply WC-Ni grades
HIP sintering for highest density
Full QC testing (dureza, densidad, microstructure)
Corrosion testing capability
Fast lead times for replacement parts
OEM customization

A strong supplier ensures stable performance and reduces equipment downtime.

Conclusión

Tungsten carbide bushings are essential components in desalination and seawater intake pumps.

Their corrosion resistance, abrasion performance, and long service life make them the best option for operators who need reliability in harsh saltwater environments.

By choosing the right binder, maintaining proper pump conditions, and working with expert suppliers, plants can operate more efficiently and reduce maintenance costs.

Si desea conocer más detalles sobre alguna empresa, no dude en contactarnos. Contáctanos.