Piping design for safety valve of hydrogen generation reactor

The stress analysis of the piping layout for reactor safety valves was performed. The results showed that,when the safety valve pipeline has horizontal π type bending on the support platform,the safety valve nozzle's maximum force in x,y and z directions in Layout Ⅰ is in the order of 136,24 and 56 N·m and the maximum displacement is in the order of 0. 25 mm,42. 92 mm and 0. 68 mm. Stress on PS-4 point is148 933. 6 k Pa,but the maximum allowable stress is 105 683 k Pa. The stress analysis check fails to meet the design requirement. After optimization of Layout Ⅰ,i. e. the shut-off valve behind the safety valve is moved to the vertical pipeline and two vertical π type bendings are provided on the pipeline to improve the pipeline flexibility( Layout Ⅱ),the safety valve nozzles maximum forces in x,y and z directions in Layout Ⅱ are235,19 and 68 N·m respectively,and the maximum displacements in x,y and z directions are 0. 36 mm,42. 92 mm and 1. 35 mm respectively. Stress values of all points in Layout Ⅱ are within the allowable range.The nozzle stresses of two layouts are small. The flange leakage check confirms that there is no leak of flange or excessive equipment nozzle stress. When the horizontal π type bending is extended from 1 000 mm to 1 500 mm,the vertical displacement of PS-1 point of support is reduced from 16. 64 mm to 4. 85 mm. In this case,the spring supports and hangers are not required. The proper position design of the pipe supports and hangers is the key factor in pipe stress checking.