A piping (1) comprises straight pipe sections (2) and curved pipe bends (3) having each an inner pipe (5; 22), an outer pipe (6; 23) and end, double-layered coupling flanges (7; 16, 17) composed of inner wear rings (8; 18, 19) and outer annular collars (9; 20, 21) with coupling grooves (10). Pipe sections (2) and/or pipe bends (3) which follow one another in sections are detachably coupled by split couplings (4) that act as revolute joints and pipe connectors. The wear rings (19) in the coupling flanges (17) of the pipe bends (3) at the outlet end of the piping have different wall thicknesses about their circumferences, while the wear rings (18) in the coupling flanges (16) at the inlet end of the piping and in the coupling flanges (7) of the pipe sections (2) have a uniform wall thickness about their circumference. The wall thickness of the wear rings (19) in the coupling flanges (17) of the pipe bends (3) at the outlet end of the piping is greater in the circumferential sections further away from the curvature mid-points (28) of the pipe bends (3) than in the circumferential sections closer to the curvature mid-points (28).