ASME B31.8S-2014 pdf – Managing System Integrity of Gas Pipelines.
8.2 Updating the Plan
Data collected duiing the inspection and mitigation activities shall bc analyzed and integrated with prcviously collected data. This is in addition to other types of integrity management-related data that is constantly being gathered through normal operations and maintenance activities. The addition of this new data is a continuous process that over time, will improve the accuracy of future risk assessments via its integration (see section 4). This ongoing data integration and periodic risk assessment will result in continual revision to the integrity assessment and mitigation aspects of the plan. In addition, changes to the physical and operating aspects of the pipeline system or segment shall he properly managed (see section 11).
This ongoing process will most likely result in a series of additional integrity assessments or review of previous integrity assessments. A series of additional mitigation activities or follow-up to previous mitigation activities may also he required. The plan shall be updated periodically as additional information is acquired and incorporated.
It is recognized that certain integrity assessment activities may be one-time events and focused on elimination of certain threats, such as manufacturing, construction, and equipment threats. For other threats, such as time- dependent threats, periodic inspection will he required. The plan shall remain flexible and incorporate any new information.
8.3 Plan Framework
The integrity management plan shall contain detailed information regarding each of the following elements for each threat analyzed and each pipeline segment or system.
8.3.1 Gathering, Reviewing, and Integrating Data.
The first step in the integrity management process is to collect, integrate, organize, and review all pertinent and available data for each threat and pipeline segment. This process step is repeated after integrity assessment and mitigation activities have been implemented, and as new operation and maintenance information about the pipeline system or segment is gathered. This information review shall be contained in the plan or in a database that is part of the plan. All data will he used to support future risk assessments and integrity evaluations. Data gathering is covered in section 4.
8.3.2 Assess Risk. Risk assessment should be performed periodically to include new information, consider changes made to the pipeline system or segment. incorporate any external changes, and consider new scientific techniques that have been developed and cornmercialized since the last assessment. It is recommended that this be performed annually but shall be performed after substantial changes to the system are made and bcfore the end of the current interval. The results of this assessment arc to be reflected in the mitigation and integrity assessment activities. Changes to the acceptance criteria will also necessitate reassessment. The integrity management plan shall contain specifics about how risks are assessed and the frequency of reassessment. The specifics for assessing risk are covered in section 5.
8.3.3 Integrity Assessment. Based on the assessment of risk, the appropriate integrity assessments shall he implemented. Integrity assessments shall he conducted using in-line inspection tools, pressure testing, andlor direct assessment. For certain threats, use of these tools may be inappropriate. Implementation of prevention activities or more frequent maintenance activities may provide a more etTective solution. integrity assessment method selection is based on the threats for which the inspection is being performed. More than one assessment method or more than one tool may he required to address all the threats. After each integrity assessment, this portion of the plan shall be modified to reflect all new information obtained and to provide for future integrity assessments at the required intervals. The plan shall identify required integrity assessment actions and at what cstablishcd intervals the actions will take place. All integrity assessments shall be prioritized and scheduled.
Table 5.6.1-1 provides the integrity assessment schedules for the external CorrOSiofl and internal corrosion time-dependent threats for prescriptive plans. The assessment schedule for the stress corrosion cracking threat is discussed in Nonmandatory Appendix A, para. A-3.4. The assessment schedules for all other threats are identified in appropriate chapters of Nonmandatory Appendix A under the heading of Assessment Interval. A current prioritization listing and schedule shall he contained in this section of the integrity management plan. The specifics for selecting integrity assessment methods and performing the inspections are covered in section 6.
A performance-based integrity management plan can provide alternative integrity assessment, repair, and prevention methods with different implementation times than those required under the prescriptive program. These decisions shall be fully documented.