Metallurgy

Wear and tear on process equipment can pose a serious problem for metallurgical enterprises. The technological processes in such production involve high temperatures, aggressive chemical environments, and interaction with abrasive materials, which naturally leads to accelerated equipment wear. The reasons why wear can become a problem in metallurgical enterprises include:

• Abrasive materials. Metallurgical processes often involve handling abrasive materials such as ores, metal oxides, and refractory materials. The continuous flow of these materials through equipment can cause erosion and abrasion, leading to surface degradation and loss of equipment integrity.
• High temperatures. Metallurgical processes require operation at elevated temperatures, which can lead to thermal stresses on equipment. Thermal cycling, thermal expansion, as well as differential heating and cooling, can contribute to material weakening, crack formation, and fractures.
• Chemical reactions. Metallurgical processes involve exposure to aggressive chemical environments, including acidic or alkaline solutions, aggressive gases, and molten metals. These chemical reactions can cause corrosion, oxidation, and chemical wear of equipment components, reducing their efficiency and lifespan.
• Mechanical loads. Equipment at metallurgical plants can experience significant mechanical loads, such as impacts, vibration, and mechanical stress. Over time, such impacts can lead to fatigue, cracking, and deformation of equipment components.
• Process variability. In metallurgical processes, raw materials, process parameters, and operating conditions can vary, affecting the wear characteristics of equipment. Depending on variability, certain equipment may be subjected to increased wear, requiring appropriate wear protection measures.

The impact of wear on a metallurgical plant can negatively affect production efficiency, equipment reliability, and maintenance costs. Excessive wear can lead to unplanned downtime, reduced productivity, and increased costs for replacement or repair. Therefore, implementing effective wear protection measures is crucial to minimize the impact of wear and extend the lifespan of equipment.

By using wear-resistant materials, coatings, and lining systems, as well as implementing maintenance and monitoring programs, metallurgical plants can mitigate the effects of wear and improve the overall performance and lifespan of their equipment. Regular inspection, maintenance, and timely replacement or repair of worn components are essential methods for ensuring uninterrupted operation and minimizing costly failures.

There are several effective methods for protecting process equipment from wear in metallurgical production, which involve the use of modern wear-resistant materials and technologies. Key methods include:

1. Bimetal technology is an effective and widely used method for protecting process equipment in metallurgical enterprises. It involves applying a wear-resistant material layer to equipment components using welding methods. The coating material typically consists of a high-strength alloy with excellent wear and abrasion resistance.
   The choice of materials for bimetallic lining depends on specific wear conditions and equipment requirements. Materials such as chromium carbide, tungsten carbide, and complex carbide alloys are commonly used for protection. These materials offer excellent hardness, impact toughness, and resistance to abrasion, impacts, and heat. Selection is based on factors such as wear type, operating temperature, and chemical environment.
   Bimetal technology can be applied to a wide range of equipment components, including chutes, hoppers, buckets, screens, liners, and pipes. It offers versatility in terms of shape and size, as the coating material can be adapted to the specific geometry and requirements of the equipment. This flexibility ensures effective protection of various types of equipment and critical wear areas.
   Thus, hard overlay welding is an effective and optimal method for protecting process equipment at metallurgical enterprises. It offers versatile and customized solutions for protecting equipment from abrasive wear, extending its lifespan, and improving overall performance. By selectively targeting high-wear areas, it provides a cost-effective approach to minimizing downtime and maintenance costs.
2. The use of cast basalt for protecting process equipment at metallurgical enterprises can be highly effective due to its unique properties and advantages, including wear resistance, impact resistance, corrosion resistance, thermal stability, and versatility. Cast basalt can be used to protect a wide range of equipment at metallurgical enterprises, including chutes and hoppers, cyclones and separators, pipes and fittings, various tanks and vessels, furnace and smelting unit components, mixer and stirrer blades. The specific areas of application for cast basalt will depend on the plant processes, equipment requirements, and wear issues.
3. The use of oxide ceramics for protecting process equipment at metallurgical enterprises can be highly effective due to its exceptional properties, with key significance in wear resistance, stability at high temperatures, corrosion resistance, and electrical insulation properties. Oxide ceramics can be used to protect various types of equipment at metallurgical enterprises, including:
   
   • Furnace linings. High alumina content ceramics can be used as refractory linings in furnaces, kilns, and other high-temperature equipment to protect against thermal wear and chemical attack.
   • Burner nozzles. Oxide ceramics can be used as burner nozzles in combustion systems, providing resistance to high temperatures, thermal shock, and chemical corrosion.
   • Thermocouple protection tubes. Oxide ceramics can be used as protection tubes for thermocouples, providing thermal insulation and protection against aggressive gases or molten metals.
   • Cruibles and ladles. Oxide ceramics can be used for lining crucibles and ladles for melting and handling molten metals, providing thermal resistance and chemical inertness.
   • Air ducts and pipes. Oxide ceramics can be used as linings for air ducts and pipes carrying corrosive gases, liquids, or abrasive materials.
   • Wear-resistant linings and plates. Oxide ceramics can be used as wear-resistant linings and plates in various equipment, including chutes, hoppers, crushers, and mills, to resist abrasion and impact loads.
   • Skip linings. Used to protect lifting and loading mechanisms from wear and damage, increasing their lifespan and efficiency.
   • Raw material hoppers. Oxide ceramics are used to protect hoppers from aggressive impacts, corrosion, and mechanical wear during the storage of various raw materials.
   • Pellet discharge vibrating chutes. Protect chutes from damage and wear during the transportation and discharge of iron ore pellets, maintaining their structural integrity.
   • Grinding element protection. Lining protects elements of mills and other grinding equipment from wear, increasing their efficiency and lifespan.
   • Aspiration duct protection. Oxide ceramics provide protection for ducts from erosion and corrosion caused by aggressive chemicals in gases.
   • Centrifugal fan linings. Protect fans from rapid wear, ensuring the reliability and stability of ventilation systems.
   • Stationary charge distributors. Used to protect distribution mechanisms from wear, improving material distribution during melting processes.
   • Throttle group lining. Protection of elements that regulate the flow and distribution of molten metal from thermal and chemical exposure.
   • Small cone protective rings. Used to reduce wear and protect critical connections in metallurgical equipment.
   • Blast furnace top gas pipelines. Lining provides protection for pipes from high-temperature impact and chemical corrosion during gas removal.
   • Receiving hoppers lining. Protects hoppers from wear and damage during raw material reception, ensuring safety and durability in operation.
   • Skip hoists. Ceramics serve as wear protection for lifting mechanisms during raw material transportation in mining and processing.