Double/Twin Ferrule Fittings

Double fittings, also known as twin ferrule fittings, are used to create leak-free tube connections quickly and easily. Double fittings consist of the following: nut, front ferrule, back ferrule, and body. Twin ferrule fittings are superior to traditional fittings due to their ferrules — metal caps or rings that help the fitting seal metal-to-metal connections and hold them in place.

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Advantages of Double/ Twin Ferrule Fittings

• Easy installation and uninstallation
• Outstanding leak- and gas-tight connections
• Withstand high temperatures, pressures, and vibrations
• Reusable multiple times

When To Use Double/Twin Ferrule Fittings

1. Fittings need to have better grip and withstand high-pressure ratings

Double ferrule fittings have a stronger mechanical grip compared to single fittings as both ferrules are holding on to the connected tube. Also, when the fitting nut is screwed on the tube, the ferrules get deformed to create a tight seal, without damaging the tube wall. This reduces leaks and damages.

2. Installations need to be disassembled occasionally, with little damage to the tubing

Installation of double ferrule fittings is smooth and quick, with no welding required. Also, any action or torque is in the fitting, with little damage to the tubing.

3. Tubes with varying dimensions and specifications need to be fitted together

The twinned ferrules can overcome variations in tubing wall thickness, hardness, and dimensional tolerance. It can be installed on thick- and thin-walled tubing and/or hard and soft tubing.

4. Require symmetrical ferrules

Double ferrule fittings only have symmetrical ferrules. Some single fittings have asymmetrical ferrules as the nut transfers torque to the ferrule as it is tightened, causing the ferrule to compress asymmetrically.

Reliable leak-free Double/Twin Ferrule Fittings in Singapore

Lian Ee Hydraulics is an established tube fitting brand in Singapore for the past 30 years. We carry a large inventory of tube fittings for reliable leak-free connection solutions. Browse our inventory below.