The devil’s in the details and that’s no lie since many intricate components are found in the most complex machines. But why is that so? Well, take a washer, for example, it’s the simplest piece of hardware yet it does such a monumental task or a multitude of them.
These small discs are placed between a fastener and its mounting surface which is why they have a hole in the middle in order to accommodate the fastener. Made out of different materials and available in different shapes and sizes, washers are more than just a connector piece, they help with so much more.
Why Choose Flat Washers?
Ductility
Flat washers are the most common type and one of the main reasons for this is the sealing properties they provide. The simple and straightforward design is what prevents air or liquids from going past round flat machine washers as they fill in the gaps no other piece of hardware can.
Reduce Wear
Any fastener can be damaged even if it’s torqued tightly as damage can occur from all those vibrations going through the bolt. To prevent the harshness of those vibrations from wearing out the bolt too much too quickly using a flat washer is necessary as instead of the bolt you’ll have the washer absorb most of the vibrations.
Protect
Since bolts are mainly made of metal and are used on metal surfaces, protecting them from galvanic corrosion is a must. While certain coatings can do that, a washer is also needed in order to prevent corrosion from coming through from a different area or component. A flat round washer also helps prevent corrosive conditions from affecting the fastener.
Versatile
Since flat washers are available in various materials and sizes they are quite versatile. You can use them in any system, component or machine as long as you go for the right type of washer depending on the above properties.
Washer Materials
Nylon
The latest material introduction to the world of flat washers is nylon. Nylon washers are made to be tough and durable without costing as much as heavier round washers. Nylon washers are able to provide a proper seal and protect from corrosion. They are also flexible which means nylon washers offer a great level of ductility, but they are however not able to survive high temperatures as well as lots of compression.
Rubber
Rubber round flat washers are similar to nylon ones as they too are quite flexible and durable. Rubber washers are also able to prevent corrosion but, like nylon washers, they are not good at withstanding high temperatures as well as high compression forces. In fact, they are much worse than nylon washers in those scenarios.
Metal
There are various types of metal washers and each one is going to be stronger than both nylon and rubber washers. Metal flat round washers are going to endure higher temperatures for much longer and survive higher compression forces too. They can rust but if they are made with the right coating they can last for quite some time.
What Matters in a Flat Washer
Washer to Bolt Strength
It’s of utmost importance that when you pair bolts and washers together you match them correctly. This means you should go with a high-strength washer if you need to use high-strength bolts. You should never use metal bolts with nylon or rubber washers and vice versa. Instead, you should use metal round washers with metal bolts, nylon with nylon and rubber with, well, plastic or something that’s not that tough as there are no bolts made of rubber.
Environment
It’s also rather important the conditions the washer is going to be used in. For instance, if the flat round washer is going to be exposed to harsh weather conditions make sure it’s properly galvanised in order to stay safe from potential corrosion, that is if it’s a metal washer. Otherwise, you won’t have to worry about corrosion. But if there are considerable levels of heat exposure then you should stay away from rubber and nylon washers or protect them from the heat if the bolts you’re using require either nylon or rubber washers to be used.
Shape
There are different kinds of shapes that flat washers are available in. Each shape is fitting in a certain scenario. For instance, spherical shape washers are made to be fitted in applications where angular misalignment needs to be corrected and to keep the bolt from bending.
Shoulder-shaped washers, on the other hand, are able to improve insulation as they are often non-metallic and their shape is in the form of a long or short barrel. This protects the fastener from both dirt and moisture. C-shaped washers are unlike any washer since they don’t have closure. The presence of the gap is what makes it easy to slide in and out without moving the bolt.
Covering All Things 