This document specifies a test method for the resistance to bending of a test piece, made of a valve assembled together with two pipes and placed between supports, when subjected to internal pressure. This document is applicable to valves with a polyethylene (PE) body for use with pipes having a nominal outside diameter from greater than 63 mm up to and including 400 mm and intended for the transport of fluids. When specified in the product standard, this document can be applied to valves of material different than PE.