1 Scope

1.1 Scope

1.1.1 This Standard covers 1/2-NPS to 12-NPS flexible metallic expansion joints intended for use in pressure systems to absorb fluctuations in the system due to thermal expansion and contraction and building structural movements. The standard specifies requirements for materials, physical characteristics, performance testing, and markings.
Note: In this Standard, "flexible metallic expansion joints intended for plumbing and non-plumbing pressure systems" are referred to as "flexible pipe loops".

1.1.2 Flexible pipe loops covered by this standard consist of two parallel sections of flexible hose oined to a rigid 180° return bend. The return bend may be a continuous pipe or tube or two 90° elbows. The flexible hose may be made up of a flexible tube, outer braid and an inner liner. An example of a flexible pipe loop and a flexible hose are shown is shown in Figure 1.