Understanding Security Chain Sizes - 90 Second Insight

13-06-2024

In the first of our 90 Second Insight videos we look at ‘Understanding Security Chain Sizes’.

Here at Insight Security we continuously strive to demystify the technicalities of the vast range of security solutions we offer from our store. We know, from the many queries we routinely receive, that security chain sizes can be very confusing. To help overcome this confusion we’ve produced the first of our 90 Second Insight videos that answers many of the questions we are often asked about security chains.

Chain Links are Made from Wire

We are all familiar with chains, made from interlocking metal loops or ‘links’. The metal used to create each individual chain link is often referred to as ‘wire’, although the dimensions are not what most of us would consider to be wire.

The chain links in security chains use wire with diameters ranging from around 6mm all the way up to 25mm. You`ll find high security chains in our store starting from 13mm diameter. If you were handling a length of metal with this dimension you are more likely to call it a metal ‘rod’. But in the context of chain manufacture this material is known as wire.

Individual chain links are made by forming lengths of this ‘wire’ into interlocking loops and then welding the two ends together. When referring to security chains the diameter of this wire is a critical attribute as this effectively defines the level of security offered by the chain. For example, a 14mm security chain is made from wire that’s 14mm in diameter and a 25mm security chain uses 25mm wire. While both of these high security chains provide excellent protection, it would take a lot longer to cut through the 25mm security chain than the 14mm chain, hence the higher security rating.

Long Link and Round Link Security Chains

Some security chains use links that are almost rectangular, with rounded ends. These are long link chains. Contrastingly, there are some security chains where the links are more circular and these are known as round link chains. Long link chains therefore use less metal to achieve a specific chain length than round link chains making them lighter. Chain weight is an important consideration for high security chains that might need to be carried, maybe on a motorcycle.

Security Chain Link Dimensions

There are three important dimensions that need to be considered for security chains. Length, width and thickness.

We’ve previously discussed the thickness of the metal used to form the chain links and how this dimension is used to categorise security chains. Another critical dimension is the width of the chain links.

chain link aperture dimensions — **Chain Link Aperture Guide**

Security chains are typically used to attach something of value to an immovable anchor point, so the security chain often needs to pass through both an appropriate aperture on the item of value and through an aperture provided by a security anchor. The width of the chain links must therefore be able to easily pass through these apertures. For example, a security chain for a motorcycle is likely to be passed through the bike wheels so the chain link width must comfortably fit between the spokes. And if this chain is then to be secured to an immovable anchor its chain link width should fit through the aperture in the anchor. When considering the chain link width for a specific application its important to make certain apertures through which the chain is required to pass will accommodate the chain link width both horizontally and vertically.

And allowance must always be made for the protective sleeve that typically sheaths motorcycle security chains to protect paintwork. Allowing an additional 5 to 6mm on top of the chain link width is recommended.

High security chains are also often used to wrap around items of value and anchor points to form a loop. Security chains for this type of application often have elongated, longer end links that allow the other end link of the chain to pass through and be secured with a padlock.