A beveled washer is a unit of hardware used with a variety of bolts and fastening devices. While a standard washer is flat on both sides with parallel surfaces, a beveled washer has one sloped side and one flat. This sloped face can be used to adjust the angle of a bolt to correct for imperfections within the structure or design of the object.
The primary function of a beveled washer is shimming or leveling an item that's out of alignment. This ensures that the fastener or bolt will fit tightly to the surrounding structure to create a secure connection. In steel construction, beveled washers are often used to meet local building codes regarding the fit and alignment of fasteners. A standard steel beam includes flanges, which typically have a slight slope. When a beveled washer is inserted between the flange and a bolt, the washer allows the head of the bolt to sit parallel to the flange as required by code.
The beveled face of these washers must be installed carefully to meet the demands of the application. When the beveled face is installed facing the head of the bolt, it can help minimize the force or stress on a specific portion of the fastener. When it is reversed so that the beveled side faces away from the bolt, the washer can spread the weight of the force more evenly across the entire structure.
When choosing a beveled washer, users should match the material to the application. Iron washers are the most malleable, and can provide a bit of flexibility for expansion and contraction. Steel units are the hardest, and provide the most strength for structural applications. If the washer will face exposure to moisture or chemicals, stainless steel should be chosen to minimize the effects or rust and corrosion.
While beveled washers can be either round or square, most users choose square or rectangular units to improve installation accuracy. Square or rectangular washers make it easier to align the bevel correctly with the fastener or surrounding object. This type of design is also less likely to rotate around the bolt, which is a common occurrence with round washers.
A beveled washer should also be sized carefully to match the fastener. The hole in the washer should be small enough to prevent the head of the fastener from passing through, but large enough for the bolt shaft to fit through fairly easily. Users must also consider the thickness of the washer as well as the slope of the bevel.