AS9120B, ISO 9001:2015, and FAA AC 0056B ACCREDITED

Different Types of Locking Wires and Their Function

On aircraft, loose hardware can cause ample damage as a result of consistent vibrations imposed on such vessels throughout flight. As such, properly building and maintaining aircraft requires one to secure all components that could negatively impact operations if they were to detach. Used extensively in manufacturing and aerospace industries, locking wires are designed to secure fasteners like cap screws, studs, nuts, bolt heads, and turnbuckle barrels in place. As a mechanical locking method especially useful for fasteners frequently exposed to vibrations, read on to learn more about how and why locking wires are able to securely reinforce fasteners in place.

The Basics

Locking wires, also called safety wires, consist of a metal wire with a diameter of 0.5 to 1 millimeters that is wrapped around one or more fasteners. As fasteners commonly loosen and dislodge from their intended application as a result of constant vibrations, locking wires keep this from happening by holding fasteners in place. More specifically, the tension the wire creates only permits the bolt head or nut to turn in the direction of tightening. When used properly, safety wires lock to keep wires taut, preventing further movement.

Types of Locking Wires

There are several different kinds of locking wires available, the most common type being medium-gauge stainless steel wires. They consist of stainless steel strands that have been woven together to offer superior strength. Though most locking wires are about 0.5 to 1 millimeters in diameter, some may be up to 1.5 millimeters in diameter, and variations in thickness tend to offer stronger protection against vibrations. Despite this, wires that are too thick for an intended application will struggle to fit over the head of its intended fastener.

Keeping Hardware Secured

In order to maintain tightly secured aircraft components, regular inspections before each flight are crucial. During every inspection, it is important to ensure that all safety wiring is tight with light tension, and each professionally-performed wire installation features about 6 to 8 twists per inch. Furthermore, while you inspect fiber or nylon locknuts, it is important to ensure that all bolts or studs extend at least a full rotation around a nut and turnbuckles have safety clips or safety wires.

Your Aviation Hardware Distributor

When you are in the market for top-quality locking wires and other aviation hardware, you can rely on our team at After Market Aviation Spares to meet your operational needs with ease. Our team is available 24/7x365 and will work diligently to get you the parts you need in rapid time with competitive pricing. With more than 2 billion new, used, obsolete, and hard-to-find components available for your purchase at any time, our database will help you fulfill all your part requirements, no matter the time constraint. When you have discovered items of interest, be sure to take advantage of our Instant RFQ service to request quotes for your comparisons. With the information you provide in each RFQ submission, our team will craft a customized solution that suits your specifications. We invite you to get in contact with us if you have any questions, and our team will be more than happy to assist you however we can throughout the procurement process.


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