What is the Difference Between Double Ferrule And Single Ferrule Fittings

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What is the Difference Between Double Ferrule And Single Ferrule Fittings

In this blog, let us discuss ferrule fittings.

What are Ferrule fittings?

A pipe ferrule is a type of pipe fitting mostly used to link or connect different pipe sections. A circular clamp is used to attach and link wires, fibers, or posts in a pipe ferrule. It’s a ring or cap that’s attached to something to protect it from splitting, damage, or wear and is commonly available in various sizes. Larger ferrule fittings are made so that they feature unique hardening patterns that can give superior resistance to leaks and tubes running at high pressures.

Ferrule Fittings come in various materials, but stainless steel is the most common, making them ideal for industrial applications.

Ferrule Fittings contain two pieces like Body and Nuts, joined together to produce a perfect union. There are two types of ferrule fittings: single ferrule and double ferrule.


Single Ferrule

The nose of the ferrule is used to serve two purposes in single ferrule fittings: the first is to bite into the tube to keep it in place, and the second purpose is to provide a sealing component for the coupling body. Single ferrule tube fittings have a substantially smaller pressure rating than their twin-ferruled equivalent. These ferrule fittings are manufactured by considering the operators’ desires and convenience of usage. It has one less part than double ferrule fittings, and additionally, it is usually hard to be placed wrongly. Despite their benefits, two ferrule tube fittings are typically favored over single ferrule fittings.


Double Ferrule

Front and back ferrules are included in the double or twin ferrule tube fittings; they have a back ferrule that grips and a front ferrule that seals. Double ferrules, often known as two-ferrules, have the exact dimensions of single ferrule fittings. Due to its sturdy mechanical grip design, twin ferrule tube fittings provide a solid connection and can connect tubing of various widths and hardness levels.

Difference between single and double ferrule fitting:


If you are working with a single ferrule fitting:

As a compression nut is tightened, the shoulder inside interacts with the back-end of the ferrule. The angled front-end of the ferrule compresses into the body and grabs the stainless steel tube under this force. In an attempt to isolate tube vibration from impacting the front end tube bite, this back-end ferrule compression action protects the front of the single ferrule.


If you’re using a double ferrule fitting:

The front ferrule is the more considerable portion that sits deepest in the body in a double or twin ferrule arrangement. The back ferrule contacts with the nut and is smaller. The front ferrule is a softer metal that bites between the tube and the fitting body to create the double ferrule seal. The lead edge on the back ferrule has been chemically toughened. This tough section can then bite down into the tubing’s softer metal, producing traction. The tube does not slip under pressure because of the gripping motion, which may be disastrous.

To address the expanding demand in sectors such as petrochemical, oil & gas, semiconductor, power, refinery, nuclear, CNG, and other essential industries, DAWSONS-TECH has developed high-quality Twin Ferrule Compression Tube Fittings, which are meticulously designed and manufactured under tight quality control methods to fulfill ISO 9001-2015 and PED 2014/68 EU regulations.