Huaneng Nantong Gas-Turbine Plant — Circulating Water Pipe up to DN2200
Project at a glance
Location
Nantong, Jiangsu, China — Huaneng gas-turbine innovation demonstration project
Scope
Circulating-water pipes and matching butt-weld fittings
Sizes
DN900, DN1220, DN1800 and DN2200 welded steel pipe
Coating
High-build coal-tar epoxy, Jotun-branded paint
Supervision
Resident representative of the construction contractor, on site throughout production
Year
2023
Scope and execution
Four diameters on one contract, with the fittings ordered against the same schedule — elbows, tees and reducers had to match the pipe wall thickness at each size so that field fit-up did not turn into site grinding. Coating was applied as a high-build coal-tar epoxy system using Jotun paint, specified by the design institute for circulating water service.
Coal-tar epoxy coated DN pipe ends, braced for transportJotun paint, as specified by the design institute, on the coating line
Points worth noting
Fittings match the pipe — butt-weld fittings produced to the same wall thickness as the corresponding pipe, so weld prep lines up on site.
Coating held to specification — high-build coal-tar epoxy applied to the DFT called for, checked wet-film and dry-film per length.
Open inspection — the contractor’s resident representative was on site for the whole production run, with free access to forming, welding and coating stations.
Relevance for power and utility projects
Circulating-water systems for gas-turbine and thermal plants typically mix several large diameters in one package. Producing them in a single campaign — pipe and fittings together — avoids the usual problem of pipe arriving before fittings and the site sitting idle.
