Pipelines, as means of transportation of water and hydrocarbon have been co<span style="white-space:normal;font-size:10pt;font-family:;" "="">nsidered “effective, safe and reliable”. O...Pipelines, as means of transportation of water and hydrocarbon have been co<span style="white-space:normal;font-size:10pt;font-family:;" "="">nsidered “effective, safe and reliable”. Over the years, pipeline failures in Niger Delta region of Nigeria have resulted in loss of lives, water pollution, soil contamination, air pollution, destruction of infrastructures and aquatic lives, and other losses. The study area, Niger Delta region is located on Latitude 4<span style="white-space:nowrap;">°</span>50</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">' </span><span style="white-space:normal;font-size:10pt;font-family:;" "="">00</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">"</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">N, longitude 6<span style="white-space:nowrap;">°</span>00</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">'</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">00</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">"</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">E and comprised of nine coastal states of Ni</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">geria (about 70,000</span><span style="white-space:normal;font-size:10pt;font-family:;" "=""> </span><span style="white-space:normal;font-size:10pt;font-family:;" "="">km<sup>2</sup>). Failure data were collected using: Questionnaires administered to experienced pipeline engineers in the International oil and gas companies (IOCs), Personnel interviews, and reports from the Department of Petroleum Resources, Nigerian National Petroleum Corporation (NNPC). This study assessed the strategies employed by four IOCs to mitigate pipeline failures in the process of asset integrity management. Design and construction methods detailing pipelines laying to infiltration</span><span style="white-space:normal;font-size:10pt;font-family:;" "=""> </span><span style="white-space:normal;font-size:10pt;font-family:;" "="">discouraging-depth were st</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">udied. The results obtained showed that vandalism is presently the major cause of pipeline failures. Deep burial solution was therefore explored as a vandalism mitigation approach and its cost of implementation for a typical Φ20</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">"</span><span style="white-space:normal;font-size:10pt;font-family:;" "=""></span><span style="white-space:normal;font-size:10pt;font-family:;" "="">× 15</span><span style="white-space:normal;font-size:10pt;font-family:;" "=""> </span><span style="white-space:normal;font-size:10pt;font-family:;" "="">km trunkline in the region showed 9.627% (</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">≈809.3 million Naira) rise co</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">mpared to the normal burial option, and this difference accrued mainly from equipment and personnel cost. This is a paltry sum compared to the huge losses due to vandalism. Finally, this study posits that the available regulatory framework is now inadequate for pipeline design, construction, and operations due to this challenge and requires urgent amendment in favour of deep burial option.</span>展开更多
Many years experience of the operation of high stress (>72% specified minimum yield strength, SMYS) gas pipelines and statistical analysis results of pipeline incidents showed that the operating pipelines at stress...Many years experience of the operation of high stress (>72% specified minimum yield strength, SMYS) gas pipelines and statistical analysis results of pipeline incidents showed that the operating pipelines at stress levels over 72% SMYS have not presented problems in USA and Canada, and design factor does not control incidents or the safety of pipelines. Enhancing pipeline safety management level is most important for decreasing incident rate. The application history of higher design factors in the U.S and Canada was reviewed. And the effect of higher factors to the critical flaw size, puncture resistance, change of reliability with time, risk level and the arrest toughness requirements of pipeline were analyzed here. The comparison of pipeline failure rates and risk levels between two design factors (0.72 and 0.8) has shown that a change in design factor from 0.72 to 0.8 would bring little effect on failure rates and risk levels. On the basis of the analysis result, the application feasibility of design factor of 0.8 in China was discussed and the related suggestions were proposed. When an operator wishes to apply design factor 0.8 to gas pipeline, the following process is recommended: stress level of line pipe hydro test should be up to 100% SMYS, reliability and risk assessment at the design feasibility or conceptual stage should be conducted, Charpy impact energy should meet the need of pipeline crack arrest; and establish and execute risk based integrity management plan. The technology of pipeline steel metallurgy, line pipe fabrication and pipeline construction, and line pipe quality control level in China achieved tremendous progresses, and line pipe product standards and property indexes have come up to international advanced level. Furthermore, pipeline safety management has improved greatly in China. Consequently, the research for the feasibility of application of design factor of 0.8 in China has fundamental basis.展开更多
文摘Pipelines, as means of transportation of water and hydrocarbon have been co<span style="white-space:normal;font-size:10pt;font-family:;" "="">nsidered “effective, safe and reliable”. Over the years, pipeline failures in Niger Delta region of Nigeria have resulted in loss of lives, water pollution, soil contamination, air pollution, destruction of infrastructures and aquatic lives, and other losses. The study area, Niger Delta region is located on Latitude 4<span style="white-space:nowrap;">°</span>50</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">' </span><span style="white-space:normal;font-size:10pt;font-family:;" "="">00</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">"</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">N, longitude 6<span style="white-space:nowrap;">°</span>00</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">'</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">00</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">"</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">E and comprised of nine coastal states of Ni</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">geria (about 70,000</span><span style="white-space:normal;font-size:10pt;font-family:;" "=""> </span><span style="white-space:normal;font-size:10pt;font-family:;" "="">km<sup>2</sup>). Failure data were collected using: Questionnaires administered to experienced pipeline engineers in the International oil and gas companies (IOCs), Personnel interviews, and reports from the Department of Petroleum Resources, Nigerian National Petroleum Corporation (NNPC). This study assessed the strategies employed by four IOCs to mitigate pipeline failures in the process of asset integrity management. Design and construction methods detailing pipelines laying to infiltration</span><span style="white-space:normal;font-size:10pt;font-family:;" "=""> </span><span style="white-space:normal;font-size:10pt;font-family:;" "="">discouraging-depth were st</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">udied. The results obtained showed that vandalism is presently the major cause of pipeline failures. Deep burial solution was therefore explored as a vandalism mitigation approach and its cost of implementation for a typical Φ20</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">"</span><span style="white-space:normal;font-size:10pt;font-family:;" "=""></span><span style="white-space:normal;font-size:10pt;font-family:;" "="">× 15</span><span style="white-space:normal;font-size:10pt;font-family:;" "=""> </span><span style="white-space:normal;font-size:10pt;font-family:;" "="">km trunkline in the region showed 9.627% (</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">≈809.3 million Naira) rise co</span><span style="white-space:normal;font-size:10pt;font-family:;" "="">mpared to the normal burial option, and this difference accrued mainly from equipment and personnel cost. This is a paltry sum compared to the huge losses due to vandalism. Finally, this study posits that the available regulatory framework is now inadequate for pipeline design, construction, and operations due to this challenge and requires urgent amendment in favour of deep burial option.</span>
基金supported by China National Petroleum Corporation Application Fundamental Research Foundation (Grant No. 07A40401)
文摘Many years experience of the operation of high stress (>72% specified minimum yield strength, SMYS) gas pipelines and statistical analysis results of pipeline incidents showed that the operating pipelines at stress levels over 72% SMYS have not presented problems in USA and Canada, and design factor does not control incidents or the safety of pipelines. Enhancing pipeline safety management level is most important for decreasing incident rate. The application history of higher design factors in the U.S and Canada was reviewed. And the effect of higher factors to the critical flaw size, puncture resistance, change of reliability with time, risk level and the arrest toughness requirements of pipeline were analyzed here. The comparison of pipeline failure rates and risk levels between two design factors (0.72 and 0.8) has shown that a change in design factor from 0.72 to 0.8 would bring little effect on failure rates and risk levels. On the basis of the analysis result, the application feasibility of design factor of 0.8 in China was discussed and the related suggestions were proposed. When an operator wishes to apply design factor 0.8 to gas pipeline, the following process is recommended: stress level of line pipe hydro test should be up to 100% SMYS, reliability and risk assessment at the design feasibility or conceptual stage should be conducted, Charpy impact energy should meet the need of pipeline crack arrest; and establish and execute risk based integrity management plan. The technology of pipeline steel metallurgy, line pipe fabrication and pipeline construction, and line pipe quality control level in China achieved tremendous progresses, and line pipe product standards and property indexes have come up to international advanced level. Furthermore, pipeline safety management has improved greatly in China. Consequently, the research for the feasibility of application of design factor of 0.8 in China has fundamental basis.