A compression fitting is a fitting used in plumbing and electrical conduit systems to join two tubes or thin-walled pipes together. In situations where two pipes made of dissimilar components should be joined (most often Pvc material and copper), the fixtures will likely be made of one or more compatible components suitable for the connection. Compression fixtures for attaching tubes (piping) commonly have ferrules (or olives within the UK) in them. Installationpartssupply Providing OEM’s and Professional Beverage Installers with Commercial Grade Installation Supplies since 95. Check out our collection of plastic tube compression fittings.

Compression fixtures are employed thoroughly in hydraulic, gas, and water systems to permit the link of tubing to threaded components like valves and resources.[1] Compression fittings are suited to a variety of programs, like plumbing techniques in confined spaces in which copper pipe will be challenging to solder without making a fire hazard, and extensively in hydraulic industrial applications. A major advantage is that the fittings permit easy disconnection and reconnection.

In small dimensions, the compression fitted consists of an external compression nut as well as an internal compression diamond ring or ferrule (occasionally called an “olive”) which is usually made from brass or copper or metal. Ferrules differ in shape and materials but are most frequently within the model of a diamond ring with beveled sides. To operate properly, the ferrule must be focused correctly, in the case of copper olives they may be usually barrel shaped and also this means they cannot be fitted incorrectly, but in which this is simply not so particularly in Hydraulic and high pressure applications the ferrule is fitted to ensure that the longest sloping face in the ferrule faces out of the nut.

If the nut is tightened, the ferrule is compressed involving the nut and the getting fitted; causing both ends of barrel shaped copper olives to get clamped around the pipe when the midst of the ferrule bows from the pipe, in the case of hydraulic design ferrules they currently have one end which is bigger having a 45 level chamfer which tapers away (from set up contact with the nut) as well as the small end generally has two inner biting edges, for applications demanding greater pressure, that penetrate the exterior diameter from the pipe, the fixtures should be tightened to recommendations depending on DIN2353 as never to surpass the stretchy limit of the metal ferrules, The result is the fact that ferrule closes the space involving the pipe, nut, and receiving fitted, therefore developing a tight joint. The clamping assistance of the pipe through the pressure on the taper at both finishes help prevent motion of the pipe inside the fitting, but it is merely the taper at the getting fitted itself that needs to seal off completely, since when it does seal off (to the pipe and also the compression fitted) then no liquid can arrive at the nut threads or perhaps the taper at the nut end to bring about any leaks. As a result some comparable fittings can be produced employing an olive with only one taper (or a repaired cone closed towards the pipe) where sealing at this taper stops fluid from getting to the nut.

Larger dimensions of compression fitting do not have a single nut to compress the ferrule but a flange using a ring of bolts that performs this. The bolts have to be tightened uniformly.

Line sealants such as joint substance (pipe dope or line seal tape like PTFE adhesive tape) are unnecessary on compression fitting threads, as it is not the thread that closes the joints but alternatively the compression in the ferrule in between the nut and pipe. However, a tiny amount of plumber’s grease or light essential oil put on the threads will give you lubrication to aid ensure a smooth, consistent tightening up of the compression nut.

It is critical in order to avoid over-tightening up the nut otherwise the reliability of the compression fitting will be affected from the excessive pressure. If the nut is overtightened the ferrule will deform improperly creating the joint to fall short. Certainly, overtightening is regarded as the typical reason behind leakages in compression fixtures. A good principle would be to tighten the nut first yourself till it is too hard to go on then tighten the nut one half-turn more using the aid of any wrench; the specific quantity differs with how big the fitted, as a larger one demands much less tightening up. The fitted will be analyzed: if minor weeping is observed, the fitted is gradually tightened till the weeping prevents.

The integrity from the compression fitted depends on the ferrule, which is effortlessly susceptible to damage. Thus care needs to be delivered to when dealing with and tightening the fitting, even though if the ferrule is ruined it is actually easily changed.

Varieties of fixtures

There are 2 kinds of compression fitted, regular (British kind-A/low-cunning) and flare fixtures (English kind-B/cunning). Standard fittings need no modifications towards the tubes. Flare fittings require modification from the tubing with a unique tool. Standard fixtures are generally utilized for water, hydraulic and compressed atmosphere contacts, whereas flare fittings can be used for gas and high pressure outlines.

A regular fitting could be installed employing an regular wrench to tighten up the surrounding nut. To eliminate it, a specialized puller is often employed to slide the nut and ferrule off of the pipe. In the event the ferrule is hard to remove it could be vulnerable with a cut, care being come to not nick the pipe while reducing.


Compression fittings are well-known because they do not require soldering, so they are relatively simple and fast to utilize. They need no unique tools or skills to function. They work on higher pressures and with harmful fumes. Compression fixtures are especially beneficial in installs that may require periodic disassembly or partial removing for maintenance and so on., because these joint parts could be damaged and remade without having impacting the integrity in the joints.[contradictory] Also, they are utilized in situations when a heat source, particularly a soldering torch, is prohibited, or where it is sometimes complicated to remove remains of water from in the pipe which prevent the pipe warming up to permit soldering.


Compression fixtures are not as sturdy as soldered fixtures. They are usually used in programs where the fitted is definitely not disrupted and not exposed to flexing or bending. A soldered joints is highly tolerant of flexing and bending (including when pipes knock or shake from sudden pressure modifications). Compression fixtures are far more understanding of these dynamic pressures. They are also bulkier, and could be regarded as less aesthetically pleasing than a nicely soldered joints. Compression fittings work dwgtgh when tightened once and never disturbed.[contradictory] Some compression connections might never be reused, for instance a ferrule ring kind. It may do not be used again once they have been compressed. This connector is immediately placed over the pipe as well as the nut is tightened compressing the ferrule involving the pipe and the entire body from the fitting. Compression of the ferrule also brings about deformation of the copper tubes. In case a compression type link has to be redone, more often than not the compressed copper/ferrule will need to be cut off and a new ferrule is going to be applied to a clear low-compressed bit of pipe end. This can be to assure a leak proof seem connection.

Tube Compression – Catering Beverage & Electrical Wholesale Equipment..