A New Shape of Expansion Loop to Compensate Thermal Expansion of Piping Systems

To provide the piping system self-compensation under the conditions in which lenticular thermal pipe expansion devices cannot be used due to the crack induced corrosion (e.g.in the Heavy Water Plant) is accomplished by special devices (e.g. U,L,Z type). Under such circumstances a novative alternative compensation solution was implemented, namely, the employment of ROTATING Z type or AA (VΛ). Such a type of compensation consists in 2× 90° pipe bends and 2× 45° pipe bends. Calculations of 15 alternative compensation solutions with more over 120 variants of materials, nominal diameter, operating conditions (Po, To) were made by running CaePipe 5.15 analysis program for 3 cases: sustained, thermal expansion and operating. The stress and distorsion conditions of the new shape satisfied the requirements in ASME Code B31.3 evidencing that this shape provides the most favorable results.