The Anahuac Mayab University is a private institution of Catholic inspiration founded in 1984.
They are used in the same applications as fender washers. A spherical washer is part of a self-aligning nut; it is a washer with one radiused surface, which is designed to be used in conjunction with a mating nut in order to correct for up to several degrees of misalignment between parts.
Lock washers are installed by putting a bolt or screw through the center of the washer, so that the washer is beneath the bolt or screw head or between the nut and the surface being fastened. Lock washers are used to keep screws and bolts from loosening, especially as a result of vibration or changes in temperature.