Did you know that pipe sizes are in Nominal Bore (NB)? This is NOT the outside measurement of the pipe. The outside diameter (OD) is the only constant measurement in pipe. The internal diameter (ID) changes depending on the wall thickness which is sorted into a size and colour code of: extra light (green), light (yellow), medium (blue) and heavy (red). These codes relate to the wall thickness available for each NB size of pipe.
So if you need to match pipe, please measure the OD of the pipe and check our Pipe Size Comparison Chart to find the NB or give us a call.