Pipeline device for reactor facility

Pored orifices each having a plurality of coolant flowing holes are disposed by multi-stages along the flowing direction in a pipeline. The diameter of the flow holes is determined by the extent of a pressure loss required depending on the diameter of the pipeline. Alternatively, eccentric single hole orifices are used. The center of the orifice hole is offset from the axial center of the pipeline. The eccentric single hole orifices are disposed such that the offsetting direction of the orifice holes is displaced by 180degC relative to the next stage by rotation around pipeline axis as a center. That is, the eccentric single hole orifices are arranged such that the center for respective orifice holes are arranged so that the centers of the respective pores are not on a line and the main orifice stream passing through the pores of a preceding orifice collides against the plate portion of a succeeding orifice. With such a constitution, a predetermined pressure loss can be obtained even if the space for laying around pipelines is narrow. Further, disturbance of streams in the pipeline is reduced, thereby enabling to reduce vibrations of the pipeline. (I.N.)