Working with copper pipe is a lot easier that working with many other types of pipe. Not only is copper light in weight and fairly cheap but it is also easy to work with. When it comes to joining two pieces of copper pipe together, you can either use a capillary joint or a compression joint. I am now going to tell you a bit more about compression joints.
So, let me start by telling you how the compression fittings got their name. The seal on a compression fitting (or joint) is made of a small ring of either copper or brass that is compressed between the actual pipe and the fitting. This ring is often referred to as an ‘olive’. The compression fitting itself is made of either brass or gunmetal. The biggest benefits of using one is that it will allow you to work with complicated pipes, making assembling, tightening, slackening and rotating them into whatever positions they need to go into, before tightening all the nuts. This differs from capillary joints which cannot be adjusted after installation. Another benefit of compression fittings is that you can dismantle them if the plumbing system ever has to be replaced or added to. I would always advice wannabe plumbers to carry spare olives, bearing in mind that they might vary slightly from brand to brand. If you are planning to join a new 22 mm pipe to an existing pipe measuring ¾ inches, you will need a special ‘adaptor compression fitting’.
Preparing and Fitting It
Before making a compression fitting you will need to prepare the pipe by cutting and cleaning it first. Also remember to clean the fitting joint before use. Once everything has been prepared, start by putting the nut over the pipe. Then add the olive and then the fitting itself. If you are working with vertical pipes, you can use clothes pegs to avoid nuts and olives from sliding down and getting in your way. Use a spanner to turn the nut on the fitting and another one to hold on to it. It is important that the pipe is pushed all the way to the stop. Avoid tightening the compression fitting too much as it can otherwise damage the olive and cause the joint to leak. It is tricky to say just how much you can tighten it but I found that you learn this really quickly through trial and error.
Best of luck!