A Brief Analysis of the Differences Between Internal and External Serrated Lock Washers

Serrated lock washers are used in conjunction with nuts on bolts, and their function is similar to that of spring washers, providing locking and anti-loosening effects. Serrated lock washers are divided into internal and external serrated lock washers. Although both serve as anti-loosening washers, there are significant differences between them. As a professional fastener manufacturer, XINCHI is happy to introduce the differences between internal and external serrated lock washers.

How Do Internal Serrated Lock Washers Prevent Loosening?

A serrated lock washer is an individual ring-shaped washer with a misaligned opening. When a wrench is used to tighten a nut, the misaligned sharp teeth of the washer engage with the component’s surface, preventing the nut from loosening. After tightening, the internal serrated lock washer exerts a backward force, achieving the anti-loosening effect.

Differences Between Internal and External Serrated Lock Washers

Differences in Appearance

Despite having similar names, the appearance of the two washers is quite different. As the name suggests, an internal serrated lock washer has serrated teeth on the inside of the washer, while an external serrated lock washer has serrated teeth on the outside of the washer, as shown in the images below:

Differences in Function

An internal serrated lock washer is used under bolts with smaller head sizes. It is commonly used in mechanical assemblies, vibration-resistant components, and sealing parts, offering stable fastening.

An external serrated lock washer is used in areas where fasteners are prone to loosening, preventing displacement or loosening of the connection. It is typically used under bolt heads and nuts.

XINCHI is a trustworthy fastener company, especially in furniture nuts. We have a factory,  founded in 2007. And we are the designated fastener supplier to“STAPLE”. As a trusted fastener supplier,  XINCHI can offer a wide range of high-quality fasteners, including nuts, screws, bolts, rivets, washers, etc. If you want to know more about fasteners or want to wholesale fasteners, please feel free to contact us. And then our experienced and expert service team will reply to you as soon as possible.