4 Different Types of Flexible Conduits Explained

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Flexible conduits play a major role when it comes to the efficient and safe wiring of an electrical system. Although the regular rigid conduits are still more popular than their flexible counterparts, you need flexible conduits every now and then, especially when you are routing wires around twists and turns. At the same time, flexible conduits offer a lot of safety features ranging from being flame-resistant, water-resistant and anti-corrosive. Here are some different types of conduits to consider for your next project.

Flexible Metallic Conduit (FMC)

The flexible metallic conduit is manufactured out of a strip of self-interlocked aluminum or steel that has been coiled. The product is a kind of hollow tube that can house wires and let them in. The flexible metallic conduit is often used in cases where a thin-walled electrical metallic conduit wouldn’t be wise, but still keeping in consideration the capacity to sufficiently protect the conductors that are to be housed inside. Despite its being flexible, you cannot expect an FMC to keep a bent position for a very long period of time. In other words, it cannot be expected to contort permanently.

Liquidtight Metallic Tubing (LMT)

large pile of flexible conduit

Liquidtight metallic tubing (LMT) is a type of flexible conduit that has the capacity to keep its inside from being penetrable by water. This makes liquid-tight metallic tubing ideal for situations where you have to protect conductors from being exposed to the harsh elements. You can even use this tubing when you have to install conductors in environments that have a lot of coolants and are often exposed to mechanical vibrations. The reason for the LMT being an efficient house for any kind of wire is that the aluminum strip that is coiled into a tube is supplemented with a flexible PVC covering that keeps everything out, making the tubing highly impenetrable.

Flexible Metallic Tubing (FMT)

Flexible metallic tubing is perfect for when you have to place wires in high places like plenum ceilings and air-handling areas. As such, flexible metallic tubing is perfect for when you are working with light fixtures and anything that would require stepping up on a ladder. The reason for such functionality is that FMT can prevent smoke and other gasses from leaking out into any air handling area. Because flexible metallic tubing is not covered by any kind of jacket, you don't have to worry about a fire burning the jacket off. Its only weakness is that you can't use flexible metallic tubing for places where moisture is sure to accumulate. FMT must only be placed in dry areas.

Liquidtight Flexible Nonmetallic Conduit (LFNC)

The safest among all the flexible electrical conduits invented, the liquid-tight flexible nonmetallic conduit is both flame-resistant and water-resistant. You can use a liquid-tight flexible nonmetallic conduit for areas that are wet, damp, and where a fire is most likely to develop. At the same time, a liquid-tight flexible nonmetallic conduit can be buried underground, as corrosion is not an issue.