Tech Talk about Metric PVC Fittings and Valves

PVC fittings and valves can be broken down in to three categories:

  • Flanged: A flanged fitting is used to bolt the metric pvc pipe to a pump, filter or other piece of equipment. The advantage of using a flange over a thread or glued joint, is that the bolts can be removed and the equipment taken away for servicing or replacement, without disturbing the pipework. Flanges require a rubber gasket to be placed between the faces.   Drillings on flanges are different in different parts of the world. In the UK and Europe, flange drillings tend to be either PN10 or PN16 (also sometimes called NP10 or NP16). North American drillings are an ANSI standard and may be referred to as ASA150 for example, and older UK flanges (more than about 30 years) may be a BS standard. Care needs to be taken to order the right drilling of flange or the bolt holes will not match up
  • Glued: A glued joint, made using PVC cement, is the most common way of joining metric pvc pipe and fittings together. Our YouTube channel has several instructional videos to help you. Gluing joint is a simple, quick process. Any metric pressure fitting, whether supplied by us or anyone else, will fit any metric pressure pipe.
  • Threaded: Threaded fittings are most commonly, like flanged fittings, used to connect to different materials. All our metric fittings had standard BSP Parallel threads, which is the most common thread you are likely to come across in the UK and Europe. If connecting to metal threads, a reinforced socket is recommended as there is a habit of over-tightening metal threads, which can split the plastic pipe fitting.
  • Our YouTube channel has videos explaining how to prepare threads correctly.

Pressure ratings

Our metric PVC fittings and valves are generally rated to 10 bar operation pressure (at 20 degrees C). There are some exceptions to this, particularly with larger fittings and valves (over 200mm), which are sometimes rated for a lower pressure. Remember that pressure ratings drop by about a sixth, every time the operating temperature increases by ten degrees. At temperatures below 20, use the 10bar pressure figure.