Abstract: In recent years, as petrochemical enterprises have further shortened the construction period of petrochemical projects, construction units must continue to innovate construction processes under the premise of ensuring quality and safety to improve construction efficiency, reduce construction costs and increase market competitiveness of enterprisesin order to meet the requirements ofbusiness environment and seek better development. Taking a petrochemical company's onsite assembly welding and installation of isopentane tower in 200kt/a isomerization unit as an example, this paper makes a comparative analysis from the aspects of construction organization and cost covering process flow, site use, supporting material input and workload, construction machinery and labor input and construction period, safety and quality assurance and so forth. This is done to explore safe, economical, and efficient construction processes suitable for the characteristics of the project, which can provide reference for the construction of similar projects.

Key words: segmented arrival, columns, pairing, lifting, labor protection, insulation, scaffolding