What Is a Flexible Electrical Conduit?
A flexible electrical conduit is a bendable tube that routes and protects electrical wiring where rigid conduit cannot fit or where movement, vibration, or tight turns are involved. It shields conductors from impact, moisture, oil, corrosion, and mechanical stress, and it is widely used to connect motors, machinery, lighting fixtures, and outdoor equipment to a fixed wiring system.
Flexible conduit comes in metal and non-metallic forms, with or without a liquid tight jacket. Choosing the wrong type leads to premature failure or failed inspections, so this guide explains the main types, the standards behind them, and how to select the right one. Kaiflex is a China-based manufacturer of flexible metal conduit systems and fittings for the US, Australian, and European markets.
What Is Flexible Electrical Conduit Used For?
Typical applications include:
Final connections to motors, pumps, compressors, and other vibrating equipment
Routing through machine frames and confined spaces with tight bends
Connecting junction boxes to lighting fixtures and HVAC units
Linking sections of rigid conduit where alignment is difficult
Outdoor and wet-location connections, such as air conditioning units and solar equipment
Industrial automation, food processing, and OEM machine building
What Are the Main Types of Flexible Conduit?
Most projects use one of three types. The table below compares them side by side.
| Feature | FMC | LFMC | LFNC |
|---|---|---|---|
| Full name | Flexible Metal Conduit | Liquid Tight Flexible Metal Conduit | Liquid Tight Flexible Non-Metallic Conduit |
| Construction | Interlocked metal strip, no outer jacket | Interlocked metal core with a liquid tight PVC jacket | PVC with an internal reinforcing spiral, no metal core |
| Best for | Dry, indoor locations | Wet, oily, or outdoor locations | Corrosive environments and outdoor equipment |
| Moisture and oil resistance | Low | High | High |
| EMI shielding | Moderate | Moderate | None |
| Typical US standards | UL 1, NEC Article 348 | UL 360, NEC Article 350 | UL 1660, NEC Article 356 |
Flexible Metal Conduit (FMC)
FMC is made from a continuous interlocked metal strip. It is economical and easy to install, which makes it a common choice for short runs in dry indoor areas. Because it has no liquid tight jacket, it is not suited to wet or oily conditions. Browse our UL flexible metal conduit range for listed options.
Liquid Tight Flexible Metal Conduit (LFMC)
LFMC adds a liquid tight polymer jacket over a metal core. The jacket keeps out water, oil, and dust, while the metal core provides crush resistance and a degree of electromagnetic shielding. It must be used with matching liquid tight fittings to maintain the seal. Jacket materials can be selected for sunlight, temperature, or chemical exposure.
Liquid Tight Flexible Non-Metallic Conduit (LFNC)
LFNC has no metal core. It is lightweight, corrosion-proof, and resistant to oil and UV, so it is often used outdoors and in chemically aggressive environments. It does not offer EMI shielding or the same crush strength as a metal core.
Which Standards Apply to Flexible Conduit?
The applicable standard depends on where the product will be installed:
North America: UL 1 (flexible metal conduit), UL 360 (liquid tight flexible metal conduit), and UL 1660 (liquid tight flexible non-metallic conduit), with installation rules in the National Electrical Code (NEC). Kaiflex UL 1 series products are listed under UL File No. E238089, and UL 360 series products under UL File No. E318661.
Europe and IEC markets: the IEC/EN 61386 series for conduit systems. See our EU flexible metal conduit and fittings.
Australia and New Zealand: the AS/NZS 2053 series. See our AS flexible metal conduit and fittings.
Always confirm the current edition of the standard and the local code requirements for your project before ordering.
How Do You Choose the Right Flexible Conduit?
Environment: dry indoor use points to FMC. Wet, oily, or outdoor use points to LFMC or LFNC.
Certification: match the standard your market or inspector requires (UL, IEC/EN, or AS/NZS).
Mechanical and EMI needs: choose a metal core for crush resistance and shielding, or non-metallic for weight and corrosion resistance.
Temperature and chemical exposure: select a jacket rated for your operating range and the substances present.
Size and fittings: match the trade size to your conductor fill and choose compatible connectors so the system stays sealed.
Why Source Flexible Conduit From Kaiflex?
Kaiflex (Flexible (Anhui) Precision Technology Co., Ltd.) manufactures flexible metal conduit and matching fittings for distributors, electrical contractors, and OEM machine builders worldwide. We supply complete conduit-and-fitting systems, which reduces compatibility problems on site, and we can discuss custom lengths and specifications for your project.
Request a Quote for Flexible Conduit
Tell us your target standard (UL, EU, or AS), conduit type, trade sizes, estimated quantity, and destination market, and our team will reply with a quotation and product recommendations. Email us at info@flexible86.com or call +86-563-6636999.
Frequently Asked Questions
What is the difference between flexible conduit and rigid conduit?
Rigid conduit is a fixed, non-bending pipe used for permanent straight runs. Flexible conduit bends to follow tight turns and absorbs vibration, so it is used for final connections to equipment and in confined spaces.
What is the difference between FMC and LFMC?
FMC is an interlocked metal conduit for dry indoor locations. LFMC adds a liquid tight polymer jacket over the metal core, making it suitable for wet, oily, and outdoor environments when used with liquid tight fittings.
Can flexible conduit be used outdoors?
Yes, but only liquid tight types such as LFMC or LFNC should be used outdoors. Standard FMC is intended for dry locations. Choose a jacket rated for sunlight exposure and the local temperature range.
Does flexible metal conduit provide EMI shielding?
A metal core provides a degree of electromagnetic shielding for sensitive circuits. Non-metallic conduit does not. If shielding is critical, tell us your requirements when you send an inquiry.
What information do I need to request a quote?
Send the conduit type, target standard (UL, IEC/EN, or AS/NZS), trade sizes, estimated quantity, and destination market. Drawings or a sample reference help us respond faster.
Looking for high-fit metal or non-metal conduits and fittings?
