Integrity Management Of Subsea Pipelines

Subsea pipelines are widely used in offshore industry to transmit oil or gas.More and more subsea pipelines are being installed.Many pipelines accidents are catastrophic,and the safety and integrity management of pipelines are related parties' primary concern now. The concept of Pipeline Integrity become especially important as a result of the Pipeline Safety Act of 2002.Integrity is the ability of a pipeline to operate safely and withstand the stresses imposed during operation.Evaluating the physical condition of an oil pipeline is critical to the pipeline operator for ensuring pipeline safety.Pipeline integrity can be determined through direct assessment methods,hydrostatic testing and inline inspection(ILI) and other measures.Pipeline integrity management is a process for assessing and mitigating pipeline risks in order to reduce both the likelihood and consequences of incidents.Several aspects of integrity management for subsea pipelines are discussed in this article.Residual strength of pipelines with defects plays an important role in subsea pipelines integrity management,however,there are hardly any exact methodology to calculate residual strength of pipelines with dent defect,equations for residual strength of dented pipelines are derived,pipeline free span,fitness for service(FFS),risk management are also discussed,related calculation examples are presented.There can be no "one approach" to integrity management.Risk management principles,if properly applied,can be powerful tools to identify the risks to pipeline integrity and should lead operators to take action to mitigate those risks.The ultimate goal of pipeline integrity management is to insure a safer human environment.More appropriate and practical codes and laws on subsea pipeline are needed in China.Integrity management of a pipeline should be started with the sound design and construction of the pipeline.Track system should be established and performance with the goals of continued improvement to ensure the reliability and safety of pipelines.