Boiler steam drum is curved. Why

Circular hoops can withstand internal pressure by pure tension in the tankmaterial instead of bending. Materials can take more force in tension than inbending.
If the shape were not circular, then there would be bending stresses in the tank wall and it would not be able to withstand as much pressure without breaking.
Spheres are more efficient than cylinders if you just care about minimizing the mass of the tank to hold a certain amount of pressurized gas. But cylinders are easier to pack together. So it’s a trade-off between efficiency and practicality.

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Main engine interlocks

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Why is a man hole door elliptical in shape?

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MEOclassIIexamnotes

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