Bimetal

Classification of Bimetals

Bimetallic protection is widely used to prevent wear in industry and can be made from various materials to meet the requirements for strength and corrosion resistance. The main types include:

• Steel Bimetal: A combination of carbon or alloy steel with high impact toughness and steel resistant to abrasive wear.
• Bimetal with Hard Alloys: Typically a combination of soft steel with inserts of tungsten carbide or ceramics, providing high wear resistance.
• Nickel Bimetal: A combination of nickel with other metals to enhance corrosion resistance and hardness.

When selecting the composition of the overlay layer, Weartech specialists are guided by years of experience and the predominant type of wear:

• CrC – Erosion, abrasive wear, deformation
• B – Strength, wear resistance
• Nb – High-speed fine particle flows
• Mo, V – Critical temperatures

It is important to consider the carbide content percentage in the overlay layer when selecting a bimetal for specific applications, with hardness not being the determining factor.

Advantages of Bimetallic Protection

Bimetallic protection offers numerous advantages, making it ideal for industrial use:

• Long service life: Due to high resistance to wear and corrosion, bimetals can significantly extend equipment operating time.
• Cost savings: Reduces repair and replacement costs by increasing maintenance intervals.
• Enhanced efficiency: Maintains optimal equipment performance by reducing wear.
• Recyclability: Some types of bimetals can be recycled, contributing to sustainable development.

Despite the many advantages, bimetallic protection has some disadvantages:

• Relatively high cost: Initial investments in bimetallic protection can be significant compared to traditional materials.
• Complexity in installation and maintenance: Specialized knowledge and tools are required for the installation and repair of bimetallic elements.
• Limited application: Some types of bimetals are not universal and may not be suitable for all operating conditions.

Application of Bimetallic Protection in the Mining Industry

Main Types of Wear in the Mining Industry

The mining industry faces various types of wear characteristic of this sector:

1. Abrasive wear: This is the most common type of wear caused by the impact of hard particles on equipment surfaces, such as during ore processing or transportation.

2. Impact wear: Occurs during strong impacts or collisions of equipment with large and heavy pieces of ore or rock.

3. Corrosive wear: Wet environments and chemically active substances can cause metal corrosion, accelerating equipment wear.

4. Erosive wear: Arises from prolonged exposure to water or other liquid flows on equipment, especially if they contain abrasive particles.

Effective Application of Bimetallic Protection in the Mining Industry

Bimetallic protection is particularly effective for protecting the following types of equipment used in the mining industry:

• Crushers: Used for crushing ore to the desired size. Bimetallic elements increase the wear resistance of crushing plates and reduce the need for frequent replacements.
• Mills: In ball and rod mills, bimetallic protection helps reduce wear on internal surfaces exposed to abrasive action during ore grinding.
• Conveyors: In transportation systems where ore is moved over long distances, bimetallic elements can protect critical areas such as blades and belts.
• Feeders and Scrapers: These devices are in constant contact with abrasive materials, and the use of bimetallic protection helps extend their service life.

The application of bimetallic lining in these areas significantly extends the service life of equipment, reduces downtime due to infrequent repairs and component replacements, and increases overall process productivity.

Use of Bimetallic Lining in the Cement Industry

Typical Types of Wear in the Cement Industry

Cement production is characterized by several specific conditions that lead to equipment wear. The main types of wear include:

• Abrasive wear: This is the primary form of wear caused by the impact of hard and abrasive particles of cement and additives on equipment, especially during mixing and grinding.
• Corrosive wear: The chemical impact of ingredients and products, including acids and alkalis, can lead to the corrosion of metal elements.
• Thermal wear: High temperatures, especially in clinker kilns, can weaken metal components and alter their properties.
• Impact wear: Strong and frequent impacts of hard materials can cause microcracks and gradual destruction of parts.

Efficiency of Bimetallic Lining in the Cement Industry

Bimetallic lining effectively protects equipment at various stages of cement production:

• Crushers: Used for crushing large chunks of raw material to the desired sizes. Bimetallic lining significantly increases the service life of wear-prone elements.
• Mills (ball and vertical): Abrasive wear in these units is significant, and bimetallic coatings can substantially reduce its impact.
• Transport systems: Conveyors and rotary feeders transporting raw material and finished products are also protected by bimetallic lining, increasing their wear resistance.
• Valves and dampers: These elements often face abrasive and impact wear during the regulation of bulk material flows.

Bimetallic lining in these applications not only increases the equipment's service life but also reduces maintenance and repair costs, which is especially important in the continuous production process characteristic of the cement industry.

Application of Bimetallic Lining in the Metallurgical Industry

Main Types of Wear in the Metallurgical Industry

The metallurgical industry faces serious challenges in terms of equipment wear, especially in steel production. The main types of wear include:

• Abrasive wear: Occurs due to the contact of equipment with abrasive materials such as ore and coke, quickly wearing down metal surfaces.
• Thermal wear: High temperatures characteristic of metallurgy can alter material properties and accelerate wear.
• Corrosive wear: Chemical exposure, such as from slags and other aggressive environments during smelting, promotes metal corrosion.
• Impact wear: Powerful impacts and loads from processing heavy metals can cause equipment destruction and deformation.
• Fatigue wear: Variable loads can cause fatigue cracks and material defects.

Effective Application of Bimetallic Lining in Steel Production

Bimetallic lining is used in various units and assemblies in metallurgy, especially in steelmaking:

• Converters and furnaces: Exposed to high temperatures and aggressive chemical impacts. Bimetallic lining can protect internal surfaces from wear and extend their service life.
• Rolling mills: Using bimetallic lining on work rolls helps reduce wear from abrasive materials and thermal impact, enhancing rolling precision and quality.
• Transport systems: Bimetallic elements in transport system components such as belts and rollers increase their wear resistance and resistance to abrasive impact.
• Loading and unloading mechanisms: These devices, often in contact with abrasive and corrosive materials, have an extended service life thanks to bimetallic components, reducing maintenance frequency.

The use of bimetallic lining in the metallurgical industry improves equipment performance and reliability, reduces maintenance and repair costs, and enhances the economic efficiency of production processes.