ISO 13967:2009

Thermoplastics fittings — Determination of ring stiffness

ISO 13967:2009 specifies a method of determining the ring stiffness of bends and branches made from thermoplastic material and for use with plastics pipes having a circular cross-section. The method can be used to determine the stiffness of bends, equal branches and unequal branches, provided the fitting allows a diametric deflection of at least 4 %.