1.1 This specification covers requirements and test methods for materials, dimensions, workmanship, markings for factory manufactured multilayer flexible steel pipe with thermoplastic inner and outer layers and end connections (Fig. 1). It covers nominal sizes 2 in. through 8 in. (50 mm through 200 mm). Flexible steel pipes are multilayered pipe products manufactured in long continuous lengths and reeled for storage, transport and installation. The multilayer thermoplastic and flexible steel pipe governed by this standard are intended for use for the transport of crude oil, natural gas, hazardous chemicals, industrial chemicals and water.2