DEYANG, China—In this verdant city deep inside China, one of the country’s oldest state-owned companies has built a 10-story-high machine that Chinese leaders hope will help it take on Boeing, the U.S. Air Force and even the U.S. space program.

The mammoth closed-die hydraulic press forge—which went into operation last year—is the largest in the world. It makes highly resilient components—such as aircraft landing gear—from titanium and metal alloys that are pressed into shape by its 80,000 tons of force.

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