This part of ISO 14531 specifies the physical properties and
mechanical-performance requirements for fullend- load-resistant
mechanical fittings for use in the connection of crosslinked
polyethylene (PE-X) pipes conforming to ISO 14531-1 and in the
construction of transition assemblies for joining PE-X pipes to
metal pipes having plain spigot, screw thread, compression socket
and flange terminations. In addition, it lays down dimensional
requirements and specifies some general material properties
(including chemical resistance) together with a classification
scheme for PE-X fitting materials produced in the form of pipe.
This part of ISO 14531, when used in conjunction with the other
parts of ISO 14531, provides the basis for the design, manufacture
and installation of PE-X piping systems (PE-X pipes, PE-X fusion
fittings and mechanical fittings) for the supply of category D and
category E hydrocarbon-based fuels (see ISO 13623) at
a) maximum operating pressures (MOPs) up to and including 16 bar
1) and
b) a maximum operating temperature of +60 °C and
c) a minimum operating temperature of
1) -50 °C
2) -35 °C
3) -20 °C.
Conformity to this part of ISO 14531-3 of mechanical fittings
produced in accordance with ISO 10838-1, ISO 10838-2 or ISO 10838-3
may be claimed subject to the satisfactory conclusion of the tests
listed in 5.6 and an end-use restriction on operating temperatures
to the temperature range -20 °C to +40 °C.
NOTE It is recognized that mechanical fittings conforming to ISO
10838-1, ISO 10838-2 or ISO 10838-3 are limited to a maximum
operating temperature of 40 °C. Provision is made in ISO 14531-4
for the use on a restricted-temperature basis of ISO 10838 fittings
conforming to 5.6 in conjunction with PE-X pipes conforming to ISO
14531-1. The fitting manufacturer's technical file should also be
consulted for relevant supporting information.
For installation purposes, this part of ISO 14531 provides for
the jointing of mechanical fittings to PE-X pipes within the
temperature range -5 °C to +40 °C.
1) 1 bar = 105 N/m2 = 100 kPa.