Pipeline Integrity Management (English Ver.)

The installation of high-pressure gas pipelines follows applicable construction norms and relevant DVGW worksheets in order to ensure the integrity of the line during installation. During pipeline operation, maintenance is of essential importance for the sustaining technical integrity. 

Preserving technical integrity and the need to use suitable management systems is required by the relevant regulations of DVGW, European regulations, and GasHDrLtgV. The creation of a unified European guideline for security management system for natural gas transport pipelines is in progress. 

The goal of Pipeline Integrity Management (PIM) for gas transport pipelines is to ensure operations with as little damage and environmental impact as possible while still being economic. 

Based on the knowledge of the status, suitable rehabilitation and maintenance measures can be planned. The derivation of measures requires a standardized description of the pipeline status and a uniform status assessment. 

The status assessment (integrity) of a pipeline is obtained by consolidating and evaluating various sources of information. They arise from the areas of operational organization, data documentation, and technical operational management. 

The task of PIM is to determine the overall process for the integrity evaluation of lines and thus to control the operative implementation of inspections, maintenance, and repairs of the pipeline network. It thus forms the connection between management, organization, information, and technology. 

Three integrity characteristics are:

• Technical integrity: Technical integrity is the sum of operational safety, availability, and environmental friendliness. It is assumed when both planning / installation and maintenance (inspection, maintenance, repair, shutdown, and decommissioning) of gas transport systems are performed in accordance with regulations and expert have approved deviations.
• Organizational integrity: Thyssengas GmbH has been audited pursuant to DVGW TSM (= technical security management). Certified auditors of the DVGW performed and confirmed this audit to verify the organization, procedures, and processes, in order to ensure that organizational integrity is given.
• Data and information integrity: Data and information integrity is the continuous availability of the data and information necessary to prove technical integrity

Pipeline Integrity Management System (PIMS) - Process

The use of PIMS should be integrated into the existing operative processes of the network technology from the beginning. The correct placement of the software was guaranteed by including all involved parties with asset responsibilities early on.

In general it is necessary to determine the pipeline status of the entire line network. Furthermore, any inspections performed during operations and individual inspections can lead to an integrity evaluation. 

Initiated by network operations, the pipeline is evaluated in PIMS. By involving network engineers and experts in the evaluation of the result, any peculiarities of a pipeline can be considered. If there is a good reason to do so, further inspection measures can be recommended. Information garnered from this are then considered in a new evaluation run.

The input data for the integrity evaluation come mainly from the data of the employed GIS system, the KKS management system, and data from performed inspection measures (KKS - intensive measurements and in-line inspections/piggings). 

The inspection data are entered into the Smallworld GIS and geo-referenced by adjusting for the equipment. Corresponding functionalities consolidate the equipment data and inspection results for the line segment to be evaluated. Afterwards, the summarized data are exported as input data for the integrity evaluation. 

The KKS management system supplies further input data relevant for the evaluation. They consist of information about KKS protective systems, soil values, and KKS effectiveness. 

Trascue PIMS prepares the different input data and forms dynamic segments. Missing input data are supplemented by estimates. 

The corrosion calculation developed during the project calculates possible corrosion damage from all available equipment and KKS information. This calculation is performed considering the different states in the life cycle of the pipeline. 

Finally, the integrity evaluation of the pipeline is performed using stress evaluation. In addition, a ranking is performed to determine reconstruction priorities.

Source:

• http://www.pipeline-conference.com/sites/default/files/papers/ptc_2012_Ruhe.pdf