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How do I identify plastic pipe fittings for socket fusion welding?


Frequently Asked Questions

Socket fusion fittings are generally marked with relevant information using characters at least 3mm high. So that they remain legible during handling, storage and installation, all identification markings are permanent and are either embossed or heat indented into the fitting.

Identification information may include:

  • manufacturer's name or identity marking
  • material type
  • relevant manufacturing standard
  • fitting size
  • fitting pressure rating
  • date of manufacture
  • fusion time
  • cooling time

For fittings of nominal size greater than 125mm, the marking may also include the SDR rating (Standard Dimension Ratio) of the fitting. SDR is the nominal outside diameter of the pipe divided by the nominal wall thickness of the pipe.

Here is an example of the identification markings on a socket fusion fitting:

PP-R d90 PN6

PP-R - material is random block copolymer polypropylene
d90 - the fitting is suitable for 90mm outside diameter pipe
PN6 - pressure rating of the fitting

See further information about plastic pipes welding and testing or please contact us.

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