You can insert curved segments when using either the Pipes & Bends or the Pipes Only pressure network layout options. A curved segment can represent flexible pipe (when the pressure pipe part has a Minimum Flex Radius greater than zero), or it can represent a series of rigid, straight pipes (when the pressure pipe part has a Minimum Flex Radius of zero).
The Run Design Check command can validate both of these types of curved pipe segments using the Radius of Curvature validation check. When the Minimum Flex Radius of the part is zero, the Radius of Curvature validation option in the Run Design Check command calculates an effective radius from the lay length and allowable deflection for the part as defined in the part catalog. This is the Minimum Effective Radius. If the radius of the curve that you insert into the drawing is smaller than the Minimum Effective Radius, the Run Design Check command reports a violation.