Resources

Choosing The Right Connection

Types of Connection

There are many types of connections for plumbing systems.  Choosing the right one means understanding your requirements and your budget.  Each style of fitting has its own strengths and weaknesses and therefore applications suitability.

Typically the main differences between different connection types are; speed of installation, permanent of temporary joins, cost and the medium being transported.  This can be seen in the table below.

Connection Type Variation
Compression Heat Free / Demountable / Easy Install
Capillary Cheap / Strong Joints
Push Fit Quick / Can Be Demountable / Heat Free
Press Quick / Heat Free
Grooved Demountable / Flexible / Heat Free
Butt Welded Stronger / Smoother Joints

Compression Fittings

Compression Fittings use an olive to create a watertight joint, which it compresses against the connecting pipe. This connection can be demounted/removed and rejoined later, or the fitting can be reused in conjunction with a new olive on a new pipe.

Compression fittings can connection to multiple types of pipe due to the nature of the connection, however when connecting to plastic pipes, a copper insert is typically used to provide support to the olive.  Specialist PEX fittings are also available which are manufactured with a support for this very reason.

As they don’t require solder or specialist tools, they can be quickly installed and uninstalled.  They also do not require heat, which afford the user a much safer installation.  This has made Compression Fittings particularly popular all over the world

Size Range

8mm – 108mm

Typical Materials

Machined Parts: CW614N
Forged Parts: CW617N
Olives: CW602N

Capillary Fittings

End Feed and Solder Ring fittings are largely made out of copper and are  connected to copper tube via Soldering or Brazing.

Soldering involves heating the fitting and pipe to very high temperatures using a blowtorch or similar.  Solder is then applied to the joint, which moves between the fitting and the pipe through capillary action.  Once the heat is removed the solder will harden forming the seal.  Brazing is largely the same, except there are much higher temperatures involved and a stronger filler material is used to create a much stronger bond.  Solder Ring fittings also come pre-soldered, meaning the installer only has to apply heat to form the seal.

Capillary fittings require more work than most connections.  They are slower to install, are not as flexible and require more preparation, however the fittings themselves are cheaper, less bulky and the joint is usually much stronger.

Size Range

8mm – 267mm

Typical Materials

Machined Parts: CW614N
Forged Parts: CW617N
Copper Fittings: CW004A

Push Fit Fittings

Push fit provide a speedy alternative to most fittings.  It works by using an O-Ring and a grab ring in tandem to provide a watertight seal and a secure joint.  Installation is as simple as pushing a pipe into the joint.  Some Push Fit fittings are demountable also, but this often proves to be quite tricky with specialist tools required to demount the fitting.

Push Fit are not recommended for every type of pipe, however the popular piping solutions are compatible.  Furthermore, different O-Rings are suitable for different applications.  Generally the manufacturer will make this easy to understand using colours to differentiate the applications.

Size Range

8mm – 54mm

Typical Materials

Machined Parts: CW614N
Forged Parts: CW617N

Press Fittings

Press fittings provide a very speedy solution for installers.  Fittings are crimped against the pipe which works in tandem with an O-Ring to create a watertight seal and a secure joint.  Installation is as simple as connecting the pipe and crimping the fitting.  Furthermore, similar to Push Fit, different O-Rings are suitable for different applications.  Generally the manufacturer will make this easy to understand using colours to differentiate the applications.

Minimal training is required for installers, however the fittings are not demountable and expensive, specialist tooling is required to install these fittings.

Size Range

12mm – 219mm

Typical Materials

Copper Press: CW004A
Stainless Steel Press: 316L