The Reactor Isn’t the Bottleneck. The Forge Is

[Marlin]

The Reactor Isn't the Bottleneck. The Forge Is

https://neutronbytes.com/2026/08/24/the-reactor-isnt-the-bottleneck-the-forge-is/

[Core Content]

The production of large reactor pressure vessels is currently limited by a global shortage of heavy forging capacity. While reactor vendors prefer integral ring forgings to minimize weld inspections over an 80-year service life, few facilities worldwide possess the necessary press tonnage and nuclear-grade quality assurance certifications to meet these demands.

This bottleneck highlights the reliance on a narrow ecosystem of suppliers in Japan, South Korea, and China. Beyond physical press size, the industry faces significant hurdles in maintaining ASME NQA-1 and Section III certifications. These rigorous quality standards require continuous audits and documentation, creating a barrier to entry that limits the number of qualified shops capable of supporting new reactor construction.

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The reactor pressure vessel is the steel shell that holds the reactor core. Vendors want it forged as a small number of large integral rings rather than many small pieces welded together. The reason is about the service life of the plant, which can run as long as 80 years.

Every weld in that vessel must be inspected on a regular schedule for as long as the plant runs. The number of welds sets the cadence for how much inspection work the plant carries forward in its service life. Fewer welds mean fewer places for a flaw to appear decades later. This is why the size and production capacity of forging presses, not welding shops, set the tempo for how fast these vessels can be produced.

Read the full article at Neutron Bytes:
https://neutronbytes.com/2026/08/24/the-reactor-isnt-the-bottleneck-the-forge-is/