A bearing surface in mechanical engineering is the area of contact between two objects. It usually is used in reference to bolted joints and bearings, but can be applied to a wide variety of engineering applications.
On a screw the bearing area loosely refers to the underside of the head.[1] Strictly speaking, the bearing area refers to the area of the screw head that directly bears on the part being fastened.[2]
For a cylindrical bearing it is the projected area perpendicular to the applied force.[3]
On a spring the bearing area refers to the amount of area on the top or bottom surface of the spring in contact with the constraining part.[4]
The ways of machine tools, such as dovetail slides, box ways, prismatic ways, and other types of machine slides are also bearing surfaces.