Hot expanded seamless steel tubes are increasingly common in daily life and have become indispensable. With growing market demand, competition among manufacturers has intensified. We must keep innovating processing technologies and continuously upgrade production standards to seize market share. This article discusses how to optimize the production process of hot expanded seamless steel tubes.
The product portfolio includes self-elevating channel steel, 690 MPa heavy plates, large-diameter seamless tubes, 460 MPa jacket channel steel and matching welding consumables, as well as heavy plates with supporting welding materials. These products are suitable for channel steel requiring high heat input welding, heavy-wall marine risers, line pipe steel and weathering steel.
Structural optimization of hot expanded seamless steel tube manufacturing processes is carried out, alongside integrated construction of logistics, energy flow and information flow networks. Matching key interfaces involves model optimization and core technologies for both long-process blast furnace-converter routes and short-process scrap-based electric furnace routes, secondary energy conversion, and recovery & utilization of low-grade waste heat. All these measures help realize low-carbon, eco-friendly iron and steel production processes.
Hot expanded seamless steel tubes mainly rely on surface anti-corrosion and anti-oxidation performance. Construction sites often have harsh working conditions, so relevant anti-corrosion performance tests have been conducted on hot expanded seamless tubes. Production must also take construction environments into consideration; modification treatment of hot expanded seamless tubes is required for extremely harsh environments. Below are the anti-corrosion construction requirements for hot expanded seamless steel tubes:
1.Before derusting, thoroughly remove surface burrs, welding slag, weld beads, spatter, dust and scale. Loose scale and thick rust layers shall be completely eliminated.
2.If acids, alkalis or salts remain on the surface of hot expanded seamless tubes, rinse thoroughly with hot water or steam. Proper wastewater treatment is required to prevent environmental pollution.
3.Anti-corrosion coating shall be applied to newly rolled steel tubes within a short period to avoid corrosion during storage and transportation. If the existing protective paint is a two-component coating cured by hardener and the coating layer remains mostly intact, sand cloth, stainless steel wire brushes or light blasting can be used for surface treatment. Proceed to the next working procedure after dust removal.
4.All oil contamination on hot expanded seamless tube surfaces shall be removed prior to derusting. Local cleaning is acceptable for partial oil stains; organic solvents or hot alkaline cleaning solutions can be adopted for full-scale or large-area degreasing.
5.Surface treatment of machined workpieces and finished products can only be performed after passing inspection.
