FORGING HOLLOW HEAVY SHAFT. (See page 420.)

No. 22. The block has a hole bored through its center, and in this the

mandrel is inserted, the tube being forged around it. The hydraulic

pressure for this 5,000-ton press is furnished by Whitworth pumping

engines. This department contains also a 2,500-ton press of similar

design.

The Wonder Book of Knowledge The Marvels of Modern Industry and Invention, the Interesting Stories of Common Things, the Mysterious Processes of Nature Simply Explained · 第 104 / 162 题