Lock Wire, Safety Wire, & Tie Wire For Aerospace | Malin Co (2024)

FAQs

What is the difference between lockwire and safety wire? ›

Lock wire's central purpose is to prevent the loosening of nuts, bolts, and other fasteners. To wire lock nuts and bolts, you thread it through two or more fasteners, ensuring they remain as secure as possible. Safety wiring prevents the loosening of fasteners by counteracting it with more tightening.

Use these types of wires for lock wire

Use monel, inconel, or corrosion-resistant lock wire in high-temperature areas. Use copper wire, 0.015 in. (0.381 mm) in diameter, on emergency equipment only. Use Clad 5056 aluminum alloy wire for lock wire that touches magnesium to prevent galvanic corrosion.

Parts shall be lock wired in such a manner that the lock wire shall be put in tension when the part tends to loosen. The lock wire should always be installed and twisted so that the loop around the head stays down and does not tend to come up over the bolt- head and leave a slack loop.

Safety wiring is used to secure components in aircraft to prevent sometimes fatal accidents. Also known as positive wire locking, safety wiring is a device that holds down parts such as nuts, bolt heads, screws, studs, and more.

Take the safety wire, thread one end of the safety wire through one of the holes and pull it back, and thread the other end through another hole in the same bolt and bring them together. Put the two ends of the wire equal in length and form a loop through the bolt head.

Safety wire is available in a variety of gauges and materials, depending on the application. In aircraft and racing applications, stainless steel wire is used, such as in 0.8 mm (0.032 in) diameter.

Basically, there are two methods of safety wiring; the double-twist method that is most commonly used, and the single-wire method used on screws, bolts, and nuts in a closely spaced or closed-geometrical pattern such as a triangle, square, rectangle, or circle.

Safety wire is necessary in areas where a bolt could loosen during vibration. Used properly, it will lock so that the wire remains taut and prevents further movement. Think of it as wearing a belt with your suspenders.

Safe-T-Cable® is designed to prevent bolts, nuts, and other fasteners from loosening in environments with excessive heat and vibration. In addition to installing three times faster than lockwire, Safe-T-Cable also produces stronger and safer results.

General Safety Wire Locking Rules

Only use the safety wire once and make sure it isn't damaged before installation. Safety wire should not be chafing or rubbing against any other parts. This can cause it to weaken or even break. The length of wire between two fasteners should be as short as possible.

Can safety wire be reused? ›

The only way to remove the locking wire/safety wire is to cut it away – meaning that it cannot be reused and a new piece must be installed every time the bolted joint is maintained.

Safety wires are made from durable steel and are designed to be strong, fire-resistant and corrosion-resistant, so they're as safe as possible. They often have copper ferrules on each end to protect the thimble eye, which is used as a connection point to prevent abrasion to the rope for added security.

A lock wire, or safety wire, is just a bit of wire that's wrapped around or through a fastener of some sort to prevent it from coming loose, due to vibrations or such. In aviation it's very common to see nuts or bolts with a safety wire.

Strong Hold: No matter which type of safety wire you choose, you can expect it to have a strong hold. The primary function of safety wire is to secure components, preventing nuts, bolts, screws and other types of fasteners from coming loose due to vibration, temperature fluctuations or other hazards of flight.

This is sort of a figure eight, with the wire bundle running through both loops of the eight. Pull the ends tight, capturing the bundle. To secure the ends and make sure the wires stay bundled, tie the ends in a simple knot, like the first step in tying a shoelace. Pull tight and tie a second hitch on top of the first.

Standard Sizes of Safety Locking Wire

091”. The most common sizes used range from . 020” to . 040”, and cover the most common applications.

Consistent Tension: Maintain consistent tension while twisting the wire to prevent loosening. The wire should be taut but not overly tight, as this can lead to breakage. Correct Twisting Technique: The wire should be twisted in a direction that tightens the fastener in case of loosening.

It is commonly used in aerospace and car industries for throttle assemblies or safety guards where extreme reliability is needed. When using lock wire, it is threaded through a hole in the fastener, twisted, then anchored to a second fastener, and twisted again.

All safety wires “must be tight after installation, but not under such tension that normal handling or vibration will break the wire.” Twists should be “tight and even, and the wire between nuts as taut as possible without over-twisting.” (Six to eight turns per inch.)

Safe-T-Cable provides a safe and consistent method for securing threaded fasteners. Traditional safety wire exhibits sharp ends that can cause harm to the operator. Safe-T-Cable does not exhibit these same characteristics and requires less manual labor and skill to install.

What is the general rule when you are lock wiring bolts together? ›

If more than three bolts are safetied together it is difficult to get the safety wire tight enough to be effective. What's wrong with this safety wire job? Many bolt heads must be safety wired to keep them from vibrating loose. As a general rule, no more than three bolts should be safety wired together.

Nylon – Nylon 6 and Nylon 11 are used for aircraft cable for high friction applications and to extend the life of the cable. The higher temperature rating of nylon makes it ideal for special applications. HDPE – HDPE is selected for use for specific and unique applications.

Hence, option D is correct. The commonly used wire in the fuse is an alloy of tin and lead.