Final answer:
Flange joints are constructed by bolting two flanges together with a gasket between their flat faces, with the gasket serving as a seal. The flat surfaces are essential for creating a tight and leak-free joint.
Step-by-step explanation:
Flange joints are made up by bolting two flanges together with a gasket between their flat faces. The correct answer is A) Flanges; Flat. Flanges are external rims, edges, ribs, or collars used to provide strength or for the attachment to another object as the flange on the end of a pipe, steam cylinder, etc. They are typically made from forging or casting and are designed to be mated with another flange.
Gaskets in flange joints serve as seals to prevent the leaking of fluids and gases in systems such as pipelines, refineries, and chemical processing plants. Proper installation and maintenance of flange joints are vital to system integrity and safety.