Washers

Flat Washer

A Flat washer is a thin plate (typically disk-shaped) with a hole (typically in the middle) that is normally used to distribute the load of a threaded fastener. High quality cap screws require hardened steel washers to prevent the loss of pre-load. These washers are also important for preventing galvanic corrosion, particularly by insulating steel screws from aluminum surfaces.

Load Indicator

Load Indicator washers are used to develop the correct tension when installing A325 or A490 structural bolts.

Spring Washer

Spring washers are non-flat washer. It has a slight conical shape which gives the washer a spring chracteristic. These washers are typically used as springs, or to apply a pre-load or flexible quality to a bolted joint. Also these are used in a number of landmines.