This document specifies the mating dimensions for thermoplastic flange adapters and corresponding loose backing flanges intended to be used in thermoplastic piping systems for the conveyance of fluids under pressure.

It applies to flange adapters and loose backing flanges for use with pipes with nominal outside diameters (d_n) from 16 mm to 2 500 mm and nominal pressures up to 25 bar[1] (PN 25).

This document specifies the dimensions of the flange adapters intended to be used for:

— butt fusion piping systems;

— socket fusion piping systems;

— adhesive jointed piping systems.

NOTE 1 For specific connections with dimensions (e.g. d_n450 or d_n630) not covered in this document, or specific equipment (butterfly valves), specific solutions are available on the market.

This document is applicable to loose backing flanges made from metal, thermoplastics, or a combination of metal and thermoplastics.

This document also provides information on gaskets and gives general recommendations on correct assembling practices.

NOTE 2 Industrial applications are not covered by this document. Products intended for industrial application are covered by ISO 15493^[1], ISO 15494 or ISO 10931^[2].

[1] 1 bar = 0,1 MPa = 10⁵ N/m².