On 30 October 2026, NuScale Power and Doosan Enerbility signed a contract at Doosan's Changwon headquarters covering manufacture of the upper reactor coolant system for the NuScale Power Module (NPM). It is a narrow scope — one section of one component — but it is the point at which the NPM programme stops being a certified drawing and starts being fabricated hardware.
The announcement, carried by World Nuclear News, describes the package as "a key component that forms the upper section of the reactor pressure vessel" that "contains the reactor coolant under high-temperature and high-pressure conditions." NuScale President and CEO John Hopkins framed it as "a meaningful step in converting our approved design into deliverable modules." Doosan's nuclear chief Jongdoo Kim called it the moment "SMR technology moves from technical validation into actual manufacturing."
What the component actually is
The NPM is a pressurised water reactor at 77 MWe per module, with the steam generators and heat-exchange equipment integrated inside the pressure vessel rather than in external loops. That architecture matters for reading this contract. The "upper reactor coolant system" is not a conventional set of loop components — hot and cold leg piping, crossover, a separate pressuriser. It is the upper closure of the RPV, incorporating the integral pressuriser volume and upper internals geometry. (This is my technical reading of the description, not a published specification.)
For the metals supply chain, that places the package in the wrought low-alloy ferritic steel family — plate or forgings, clad on wetted surfaces, with the flange region a demanding forging and welding proposition. The cladding, welding consumables and any nickel-alloy internal fitments are where the upstream specialty-metal value sits. Exact grades, ASME section and class, forging envelope and tonnage are not disclosed in any source reviewed for this article, and should not be assumed from other PWR programmes.
Continuity, not a new start
The contract formalises a relationship that is longer and more consequential than the headline suggests:
| Date | Milestone |
|---|---|
| 2019 | NuScale–Doosan partnership begins; manufacturing processes, supply chain and production infrastructure developed jointly |
| Sept 2020 | NPM becomes the first SMR design to receive US NRC approval |
| March 2023 | NuScale places its first upper reactor pressure vessel long-lead production order with Doosan — for the Carbon Free Power Project |
| 2023 | Separate Doosan–NuScale contract to manufacture materials for the SMR |
| Nov 2023 | NuScale and UAMPS mutually terminate the CFPP (six modules, 462 MWe) |
| Oct 2026 | Formal contract for upper reactor coolant system fabrication at Changwon |
The most important line in that table is the 2023 one. The component now under contract was first ordered as a long-lead item three and a half years ago. Following the CFPP termination, NuScale has said it intends to transfer those modules to its next customer. So this is less "new order" than re-validation and carry-forward of an existing commitment to a project that has since changed. Readers should note that WNN does not state that the long-lead material has been contractually reallocated to a named project.
Doosan's own framing supports the continuity reading: the companies are "expanding their collaboration from material preparation to the fabrication of reactor components for commercial deployment." The same statement looks forward — "significant manufacturing capacity will be required" and Doosan "plans to further strengthen its supply chain and manufacturing readiness to support follow-on orders." That is an expectation, not an awarded package.
Where the modules are going
The first-of-a-kind reference plant has moved. WNN states the FOAK NuScale project is now set to be built at the former coal plant site at Doicești, Romania — the RoPower project. This article does not establish module count, contract value or a firm construction schedule for Doicești; related WNN coverage indicates a final investment decision has been taken on the Romanian project, but that item could not be read in full for this analysis and its figures should be treated as unconfirmed.
A separate strand visible in WNN's coverage — at least two steam generator tube contracts with Sweden's Alleima — points to parallel specialty-tubing procurement for the integrated steam generators. Those too are outside the scope of the contract discussed here.
Commercial read-across for steel and heavy fabrication
What is settled: the fabricator is chosen, the site is Changwon, and the component class is defined. Doosan has held the NPM upper RPV workstream since 2023 and now has a fabrication contract rather than a material-preparation arrangement.
What remains genuinely open (per available evidence, not confirmed as procurement opportunities):
- Mill orders for the forging/plate feedstock behind the upper reactor coolant system. Whether this runs through Doosan's existing qualified supply chain or opens new mill qualification is not public.
- Contract value, delivery date and the number of module sets covered.
- The EPC/EPCI tier for Doicești. No contractor is identified in the evidence reviewed.
- Follow-on module orders. Doosan's readiness language anticipates them; nothing has been awarded.
One structural point deserves emphasis for anyone tracking nuclear steel demand. Integrated-vessel SMR architectures reduce the conventional loop-piping and heavy component count per MWe relative to a large PWR, but they increase the complexity and inspection burden of the vessel itself — more cladding, more internal structures, tighter tolerances, and forging capacity that is scarce globally. The bottleneck for NPM scale-up is less tonnage than qualified heavy-forging and cladding slots. Doosan's statement about capacity is a tacit acknowledgment of exactly that.
What to watch
- First cut of metal at Changwon — the transition from contract to active forging is the real signal.
- Reallocation language — confirmation that the 2023 long-lead material is formally tied to Doicești or a US deployment.
- A multi-module frame agreement — a single-component contract is a pilot; a fleet order is the commercial event that matters for upstream mills.
- EPC selection for Doicești — the tier that typically controls bulk steel and balance-of-plant awards.
NuScale has crossed a threshold that several SMR developers have not: a certified design with a contracted fabricator and a named reference site. The contract itself is modest in scope and undisclosed in value. Its significance lies in what it de-risks — manufacturing process maturity — rather than in what it procures.