Software And Technique On The Resistance To The Ratcheting Deformation Of Pressurized Piping And First Aid Repair

Three methods were employed to evaluate the ratcheting boundaries ofpressurized piping in PWR nuclear power plant including using the three-point beamtest results, simulating via ANSYS software combined with ratcheting rate controlmethod suggested by C-TDF and employing nuclear power plant mechanical designand construction process, like ASME, KTA and RCC-MR codes. Ratchetingboundaries determined by codes were found to be somewhat conservative, comparedwith those obtained from test results. Ratcheting boundaries of pipe under constantinternal pressure and cyclic bending moment determined by finite element methodwith the plastic models were also lower than those gained from test results, whichcertify that the finite element method is feasible to check the ratcheting effect.According to the software engineering theory and parametric modelingtechnology, the stress assessment software based on software collaboration withVisual Basic2005as developing environment has been designed based on OOP(oriented object programming) method. The system contains four parts: RatchetingEffect Check Module, Stress Check Module, Fatigue Check Module and DatabaseManagement Module. In the case of real work condition, ratcheting boundary curvesobtained from the finite element method or the test results and simplified fatiguemethod derived from RCC-M code were used as ratcheting and fatigue failure criteriafor engineering design, respectively.The methods of pipeline first aid repair technique applied to actual conditions ofpipeline companies were discussed. In order to restore the damage of the pipelinecaused by leakage, oil-robbing and natural factors induced defects, the software forrush-repair of pipeline has been developed, and can be used to guide pipeline repairby repair team to ensure the lifecycle management of oil and gas pipelines.