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Rainflow Cycle Counting Analysis Providing cutting edge analysis for superior integrity management CC Technologies and DNV (CCT/DNV) are now one company providing you with the most dynamic methods of performing Rainflow Cycle Counting •
Rainflow Cycle Counting Basics
Rainflow cycle counting (RCC) is a tool used to evaluate fatigue damage incurred on a pipeline due to internal pressure fluctuations. Pressure cycles are assessed for how large and how often pressure changes within the pipeline. Traditionally RCC has only been performed on a station to station basis. CCT/DNV has expanded on the basic concept of RCC to offer you a vast • array of analysis options which can be tailored to meet your needs.
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Baseline Comparisons: RCC results are analyzed on a yearly basis to determine the trend of the pressure cycle severity.
Getting More From RCC
RCC Analysis Options •
Fatigue Life Calculations: Crack growth rates are determined based on RCC fatigue damage calculations. Those results can be used in unison with either in-line inspection (ILI) or hydrostatic test data to approximate the remaining life of a pipeline.
CCT/DNV uses RCC analyses to determine where things such as early generation seam welds are subjected to aggressive pressure cycles. In addition, stress corrosion cracking (SCC) growth rates can be estimated in areas where near-neutral-pH SCC is a threat. RCC is an excellent supplement for determining reassessment intervals or as a tool to prioritize line segments for inspection. Customizable reports can be provided to meet your needs. CCT/ RCC along a Pipeline: This option takes into account DNV offers RCC capabilities that no other contractor can match. pressure changes due to gravity and head losses. Pressure cycles are counted at any point along a pipeline. Basic RCC Analysis: This option is best used as a screening tool to determine the need for a more detailed assessment. CCT/DNV performs Basic RCC in accordance with ASTM 1049-85, 1997, “Standard Practices for Cycle Counting in Fatigue Analysis”.
Dublin, Ohio 43017 USA 614.761.1214 Calgary, AB Canada T2E 8M5 403.250.9041 www.cctechnologies.com Email: integrity.cct@dnv.com (USA) info.cctcanada@dnv.com (Canada)