The high-pressure water-tube boiler of the experimental LNER W1 10000 Hush-Hush steam locomotive. Rated at 450 psi (3.10 MPa), the boiler has 2.5 times pressure than its contemporary, the Gresley A1.
https://diqn32j8nouaz.cloudfront.net...000_boiler.jpg
Previously:
https://www.homemadetools.net/forum/...827#post156235
https://www.homemadetools.net/forum/...445#post154762
https://www.homemadetools.net/forum/...821#post148364
