As an important part of the petrochemical industry, the stability and reliability of the quality and performance of petrochemical forgings are of great significance to the operation safety and service life of the entire equipment. However, petrochemical forgings are often affected by various environmental factors in the process of production, transportation and use, leading to problems such as corrosion and wear on the surface, which in turn affect their performance. Therefore, the surface treatment and protection technology of petrochemical forgings is particularly important. This paper will discuss the surface treatment and protection technology of petrochemical forgings, aiming at improving the corrosion resistance and wear resistance of petrochemical forgings and prolonging their service life.
Surface treatment technology of petrochemical forgings
Cleaning: Before surface treatment, petrochemical forgings must be thoroughly cleaned to remove impurities such as oil and oxide on the surface. The cleaning method can be chemical cleaning, mechanical cleaning or electrochemical cleaning.
Rust removal: For rusty petrochemical forgings, rust removal is required. The commonly used rust removal methods include mechanical rust removal, chemical rust removal and electrochemical rust removal. Rust prevention treatment should be carried out immediately after rust removal to prevent rust again.
Rust prevention: Rust prevention treatment is an important measure to protect the surface of petrochemical forgings from corrosion. The commonly used anti-rust methods are coating anti-rust, passivation anti-rust and oil film anti-rust. Anti-rust coating can form a dense protective film on the surface of the forging, isolate air and moisture, and prevent corrosion; Passivation anti-rust can form a stable passivation film on the forging surface through chemical reaction to improve corrosion resistance; Oil film rust prevention can form a layer of oil film on the surface of the forging, which plays a lubricating and anti-corrosion role.
Shot peening: Shot peening is a method of impact treatment on the forging surface by spraying high-speed projectiles, which can remove the surface micro-cracks and residual stress, and improve the fatigue strength and corrosion resistance of the forging.
Chemical coating: Chemical coating is a method of forming a layer of metal or non-metal coating on the surface of the forging through a chemical reaction, which can improve the corrosion resistance, electrical conductivity and decoration of the forging. Common chemical coatings are zinc plating, chromium plating, nickel plating and so on.
Protection technology of petrochemical forgings
Coating protection: Coating protection is a method of preventing corrosion and wear by applying a protective coating to the surface of the forging. Commonly used protective coatings are anti-corrosion paint, wear-resistant coating, conductive coating and so on. Coating protection has the advantages of convenient construction and low cost, but it needs to pay attention to the quality and thickness control of coating.
Metal spraying: Metal spraying is a method by spraying metal powder on the surface of the forging and heating it to melt to form a coating, which can improve the corrosion resistance and wear resistance of the forging. Commonly used metal spraying materials are zinc, aluminum, stainless steel and so on. Metal spraying has the advantages of controllable coating thickness and strong binding force, but it requires high equipment investment and operation technical requirements.
Electrochemical protection: electrochemical protection is a method of forming a protective film on the surface of the forging by electrochemical method to prevent corrosion. Common electrochemical protection methods include anodic oxidation, cathodic protection and so on. Electrochemical protection has the advantages of good protection effect and long service life, but it requires high equipment investment and maintenance cost.
Chemical conversion film: Chemical conversion film is a method of improving corrosion resistance by forming a layer of chemical conversion film on the surface of the forging. Common chemical conversion films are phosphating film, oxide film and so on. The chemical conversion film has the advantages of low cost and convenient construction, but attention should be paid to the thickness and uniformity control of the conversion film.
Through the discussion of the surface treatment and protection technology of petrochemical forgings, it can be seen that these technologies play an important role in improving the corrosion resistance and wear resistance of petrochemical forgings to extend their service life. In the future, with the continuous progress of science and technology and innovation, the surface treatment and protection technology of petrochemical forgings will be further improved and applied to make important contributions to the sustainable development of the petrochemical industry.
