Coating-protected valves are special industrial valves developed exclusively for the harsh operating conditions of the petrochemical industry. By relying on advanced thermal spraying processes such as plasma spraying, high-velocity oxy-fuel (HVOF) spraying and arc spraying, high-performance protective coatings are applied to the surface of valve substrates, fundamentally enhancing the valves' corrosion resistance, wear resistance, high-temperature resistance and medium erosion resistance. These valves are suitable for the entire range of petrochemical scenarios including crude oil extraction, refining and processing, oil and gas transportation, and chemical reactions, and can effectively address the industry pain points of traditional valves such as easy corrosion, wear and short service life when exposed to strong acids, strong alkalis, high sulfur content and particle-containing media. The product boasts prominent core advantages: first, superior corrosion resistance—targeting common corrosive media in the petrochemical industry such as H₂S, Cl⁻, organic acids and strong alkalis, customizable protective coating systems including nickel-based alloy coatings, ceramic coatings and fluoroplastic composite coatings are available; among them, nickel-based alloy coatings can withstand corrosion from high-sulfur oil and gas media in oil and gas fields, ceramic coatings can resist erosion from high-temperature acid and alkali media in refining units, and fluoroplastic coatings exhibit excellent resistance to strong oxidizing chemical media (such as concentrated nitric acid and concentrated sulfuric acid), extending the corrosion-resistant service life of valves by 5–10 times compared with traditional uncoated valves; second, excellent wear resistance and erosion resistance—to tackle the erosion and wear issues caused by particle-containing media such as sand-containing crude oil, fluid catalytic cracking catalyst particles and coal-to-liquid slurries, WC-Co cemented carbide coatings and Cr₂O₃ ceramic coatings are adopted, with coating hardness reaching above HV1000 and bonding strength exceeding 50MPa, which can effectively resist erosion and abrasion from high-speed media, prevent wear failure of key valve components such as sealing surfaces, valve seats and valve stems, and ensure long-term sealing reliability of the valves; third, high-temperature and high-pressure stability—the coating system can adapt to the high-temperature and high-pressure operating conditions of the petrochemical industry (temperature range: -20℃~800℃, pressure range: PN16~PN420); vitrified bond coatings have excellent thermal shock resistance without cracking or peeling during repeated heating and cooling cycles; nickel-based high-temperature alloy coatings can maintain structural stability under high-temperature operating conditions above 600℃, meeting the valve application requirements of high-temperature equipment such as hydrogenation reactors and reforming units; fourth, zero-leakage sealing guarantee—the valve sealing surfaces adopt the "substrate precision grinding + coating reinforcement" process, with the coating surface roughness controlled below Ra0.2μm; combined with high-precision grinding technology, bubble-level sealing of valves is achieved, complying with petrochemical valve sealing standards such as API 6D and GB/T 12224, which can effectively prevent leakage of flammable, explosive, toxic and harmful media and ensure production safety. The product structure and coating process are strictly designed: valve substrates are selected from materials such as carbon steel (WCB), stainless steel (304/316L), duplex stainless steel (2205) and Hastelloy according to operating conditions, ensuring the substrate has sufficient strength and stress corrosion resistance to provide a stable bonding base for the coating; the core coating system is diverse—WC-Co cemented carbide coatings are suitable for particle-containing medium erosion and wear conditions, typically applied to ball valve spheres, gate valve discs and valve seat sealing surfaces; nickel-based alloy coatings are suitable for high-sulfur oil and gas corrosion conditions, typically applied to gate valves and globe valves in oil and gas transmission pipelines; Al₂O₃-TiO₂ ceramic coatings are suitable for high-temperature acid and alkali corrosion conditions, typically applied to high-temperature butterfly valves and check valves in refining units; PTFE composite coatings are suitable for strong oxidizing chemical medium conditions, typically applied to ball valves and control valves supporting chemical reactors; advanced spraying processes are adopted to ensure quality—WC-Co cemented carbide coatings are prepared by HVOF spraying with a coating density of up to 99.5% without pores or cracks; ceramic coatings are prepared by plasma spraying with good uniformity and a controllable thickness range of 50μm–500μm; all coatings undergo strict post-treatment (grinding, polishing, sealing) to further enhance the protective performance and surface precision of the coatings. The product range covers all types of petrochemical valves: gate valves, globe valves, ball valves, butterfly valves, check valves, control valves, plug valves, etc., with nominal diameters ranging from DN15 to DN2000 and nominal pressures ranging from PN16 to PN420, suitable for media including crude oil, natural gas, refined oil, acid-alkali solutions, chemical raw materials and coal slurries; in the oil and gas field extraction sector, they are adapted for wellhead valves and gathering pipeline valves in high-sulfur oil and gas wells to resist H₂S stress corrosion cracking; in the refining and processing sector, they are adapted for valves in fluid catalytic cracking and hydrofining units to withstand erosion and corrosion from high-temperature media; in the chemical production sector, they are adapted for valves supporting acid-alkali storage tanks and reactors to meet the sealing requirements of strong corrosive media; in the oil and gas transportation sector, they are adapted for ball valves and gate valves in long-distance pipelines to resist soil corrosion and medium erosion. Backed by a professional thermal spraying R&D center, we can provide customized coating solutions according to customers' specific operating condition requirements, including coating material selection, thickness design and spraying process optimization; we can also offer one-stop services covering overall valve design, manufacturing, spraying and testing. The entire product process complies with standards such as API 600, API 6D and GB/T 12224; before leaving the factory, all valves undergo strict coating adhesion testing, corrosion resistance testing, pressure and sealing testing, and wear testing to ensure each valve meets the stringent requirements of the petrochemical industry. Coating-protected valves can significantly extend the service life of valves, reduce equipment maintenance frequency and replacement costs, minimize unplanned downtime caused by valve failure, improve the operational stability and safety of petrochemical units, and create greater economic benefits for customers.

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