|
|
|
|
|
 |
|
|
Stainless Steel Fasteners - Washers |
|
|
A 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. Other uses are as a spacer, spring, wear pad,
preload indicating device, and locking device. Washers usually have an
outer diameter (OD) about twice the length of their inner diameter
(ID).
High quality capscrews require hardened steel washers to prevent
the loss of pre-load due to Brinelling after the torque is applied.
While they may look similar, washers and gaskets are usually designed
for different functions and made differently.
Washers are also important for preventing galvanic corrosion,
particularly by insulating steel screws from aluminum surfaces.
Countersunk Finishing Washers
Countersunk finishing washers or "cup washers" are designed to
provide a finished look with use of countersunk screws (usually flat or
oval head). They are also available in Zinc, Black Zinc
or Black Oxide Plated Steel.
Tooth Washers
A locking washer with teeth or prongs which extend from either the
inside edge (Internal Tooth Washers), the outside edge (External Tooth
Washers) or both (Internal/External Combination). The teeth maintain
essential tension and oppose any loosening influences on the fastener.
The flexed teeth absorb shock, vibration and slipping. They are also
available in Zinc plated, Yellow Zinc, Black Zinc or Black
Oxide Plated Steel.
Lock Washers
A helical spring lock washer is a flat washer with a cut on one
side, slightly twisted so that the free height is approximately twice the
thickness of the washer section. They have the function of providing
greater bolt tension, providing hardened bearing surfaces to create more
uniform torque control and providing protection against looseness
resulting from vibration and corrosion. Lock washers are also available in
steel and high alloy steel in Regular, Heavy or High
Collar styles as well as fully certified
military standard.
Flat Washers
Flat washers are used under the head of a bolt or screw or over a
nut to provide a greater bearing surface. When tightening this will
distribute the forces and prevent the bolt, screw or nut from breaking
through the material. Flat washers are also available in
mild steel, hardened alloy steel and Nylon 6/6. There are
a variety of styles of flat washers which differ mostly in the outside
diameter dimension. The most common flat washers are the USS and SAE
style. Flat washers that comply to
fully certified military standards are also available.
|
|
|
|
|
