• Title/Summary/Keyword: Pipelines

Search Result 828, Processing Time 0.025 seconds

Implementation of Pipeline Monitoring System Using Bio-memetic Robots (생체 모방 로봇을 이용한 관로 모니터링 시스템의 구현)

  • Shin, Dae-Jung;Na, Seung-You;Kim, Jin-Young;Jung, Joo-Hyun
    • The KIPS Transactions:PartA
    • /
    • v.17A no.1
    • /
    • pp.33-44
    • /
    • 2010
  • We present a pipeline monitoring system based on bio-memetic robot in this paper. A bio-memetic robot exploring pipelines measures temperature, humidity, and vibration. The principal function of pipeline monitoring robot for the exploring pipelines is to recognize the shape of pipelines. We use infrared distance sensor to recognize the shape of pipelines and potentiometer to measure the angle of motor mounting infrared distance sensor. For the shape recognition of pipelines, the number of detected pipelines is used during only one scanning of distance. Three fuzzy classifiers are used for the number of detected pipelines, and the classifying results are presented in this paper.

Comparison of Numerical and Experimental Stability of Dual Subsea Pipeline in Trench (트렌치내에서 복합 해저 관로 안정성의 수치해석과 실험해석 비교)

  • Chul H. Jo;Young S. Shin;Sung G. Hong;Kyoung H. Min;Chung, Kwang-Sic
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
    • /
    • 2001.05a
    • /
    • pp.254-259
    • /
    • 2001
  • There are advantages in the installation of dual subsea pipelines over two separate single lines. In many case it can reduce the cost for trench, back-filling and installation. However the installation of dual pipelines often requires technical challenges. Dual Pipelines should be placed to be stable to external loading not only during the installation but also in the design life. Dual pipelines in trench can reduce the influence of external forces. To investigate applied forces as slope changes, number of experiments are conducted with PIV (Particle Image Velocimetry) in a circulating water channel. Numerical approaches are also made to compare with experimental results. The velocity fields around dual pipelines in trench are investigated and analysed. Comparison of both results show similar pattern of flow around dual pipelines. it is proved that the trench slope affects the pipeline stability significantly. The results can be applied in the stability design of dual pipelines in trench section. The complex flow patterns can be referenced effectively linked in the understanding of fluid around circular bodies in trench.

  • PDF

Anticorrosive Monitoring and Complex Diagnostics of Corrosion-Technical Condition of Main Oil Pipelines in Russia

  • Kosterina, M.;Artemeva, S.;Komarov, M.;Vjunitsky, I.;Pritula, V.
    • Corrosion Science and Technology
    • /
    • v.7 no.4
    • /
    • pp.208-211
    • /
    • 2008
  • Safety operation of main pipelines is primarily provided by anticorrosive monitoring. Anticorrosive monitoring of oil pipeline transportation objects is based on results of complex corrosion inspections, analysis of basic data including design data, definition of a corrosion residual rate and diagnostic of general equipment's technical condition. All the abovementioned arrangements are regulated by normative documents. For diagnostics of corrosion-technical condition of oil pipeline transportation objects one presently uses different methods such as in-line inspection using devices with ultrasonic, magnetic or another detector, acoustic-emission diagnostics, electrometric survey, general external corrosion diagnostics and cameral processing of obtained data. Results of a complex of diagnostics give a possibility: $\cdot$ to arrange a pipeline's sectors according to a degree of corrosion danger; $\cdot$ to check up true condition of pipeline's metal; $\cdot$ to estimate technical condition and working ability of a system of anticorrosive protection. However such a control of corrosion technical condition of a main pipeline creates the appearance of estimation of a true degree of protection of an object if values of protective potential with resistive component are taken into consideration only. So in addition to corrosive technical diagnostics one must define a true residual corrosion rate taking into account protective action of electrochemical protection and true protection of a pipeline one must at times. Realized anticorrosive monitoring enables to take a reasonable decision about further operation of objects according to objects' residual life, variation of operation parameters, repair and dismantlement of objects.

Cathodic Protection of Onshore Buried Pipelines Considering Economic Feasibility and Maintenance

  • Choi, Byoung-Yeol;Lee, Sang-Gil;Kim, Jin-Kwang;Oh, Jin-Soo
    • Journal of Advanced Research in Ocean Engineering
    • /
    • v.2 no.4
    • /
    • pp.158-168
    • /
    • 2016
  • During the installation of crude oil or gas pipelines, which pass through onshore buried pipelines or onshore pipeline from subsea pipeline to onshore plant, countermeasures need to be implemented so as to ensure a sufficient design life by protecting the steel pipes against corrosion. This can be achieved through impressed current cathodic protection method for onshore pipelines and through galvanic sacrificial anode corrosion protection method for offshore pipelines. In particular, in the case of impressed current cathodic protection, isolation joint flanges should be used. However, this makes maintenance control difficult with its installation having a negative impact on price. Therefore, in this study, the most suitable methodology for onshore pipeline protection between galvanic sacrificial anode corrosion protection and impressed current cathodic protection method will be introduced. In oil and gas transportation facilities, the media can be carried to the end users via onshore buried and/or offshore pipeline. It is imperative for the field operators, pipeline engineers, and designers to be corrosion conscious as the pipelines would undergo material degradations due to corrosion. The mitigation can be achieved with the introduction of an impressed current cathodic protection method for onshore buried pipelines and a galvanic sacrificial anode corrosion protection method for offshore pipelines. In the case of impressed current cathodic protection, isolation joint flanges should be used to discontinuity. However, this makes maintenance control to be difficult when its installation has a negative impact on the price. In this study, the most suitable corrosion protection technique between galvanic sacrificial anode corrosion protection and impressed current cathodic protection is introduced for (economic life of) onshore buried pipeline.

Vibration Velocity Response of Buried Gas Pipelines according to Train Speed (지중 매설 가스 배관의 열차 주행 속도에 따른 진동 속도 특성)

  • Kim, Mi-Seung;Sun, Jin-Sun;Kim, Gun;Kim, Moon-Kyum
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2008.04a
    • /
    • pp.561-566
    • /
    • 2008
  • Recently, because of development of the high speed train technology, the vibration loads by train is significantly increased ever than before. This buried gas pipelines are exposed to both repeated impact loads, and, moreover, they have been influencing by vibration loads than pipeline which is not located under vehicle loads. The vibration characteristic of pipeline is examined by dynamic analysis, and variable is only train speed. Since an effect of magnitude of vibration loads is more critical than cover depth, as increasing the train speed, the vibration speed of buried pipelines is also increased. The slope of vibration velocity is changed by attenuation of wave, at train speed, 300 km/h. From the analysis results, the vibration velocity of pipelines is satisfied with the vibration velocity criteria which are established by Korea Gas Corporation. The results present operation condition of pipelines under rail loads has fully sound integrity based on KOGAS specification.

  • PDF

A study on the corrosion evaluation and lifetime prediction of fire extinguishing pipeline in residential buildings

  • Jeong, Jin-A;Jin, Chung-Kuk;Lee, Jin Uk
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.39 no.8
    • /
    • pp.828-832
    • /
    • 2015
  • This study is conducted for the evaluation of corrosion and lifetime prediction of fire extinguishing pipelines in residential buildings. The fire extinguishing pipeline is made of carbon steel. Twenty-four samples were selected among all the fire extinguishing pipelines in a building; the selection was based on specimenspositions, pipeline diameters, and pipeline thickness. Analysis was conducted by using the results of visual inspection, electrochemical potentiodynamic anodic polarization test, pitting depth measurements, and extreme value statistics with the Gumbel distribution. The maximum pitting depth and remaining life were statistically predicted using extreme value statistics. During visual inspection, pitting corrosion was observed in several samples. In addition, extreme value statistics demonstrated that there were several pipelines that were very sensitive to pitting corrosion. However, the pitting corrosion was not critical in all the pipelines; thus, it was necessary to change only those pipelines that were severely corroded.

Reliability Estimation of Gas Pipelines Damaged by External Corrosion (외부부식에 의해 손상된 배관의 신뢰성평가)

  • Jin, Yeung-Jun
    • Journal of the Korean Society of Safety
    • /
    • v.21 no.2 s.74
    • /
    • pp.1-6
    • /
    • 2006
  • It is well known that pipelines have the highest capacity and are the safest and least environmentally disruptive form of transporting oil and gas. However, pipeline damage caused by both internal and external corrosion is a major concern threatening the reliability of oil and gas transportation and the soundness of the pipeline structure. In this study, we estimate the allowable damage by comparing the ASTM B31G code to a modified theory considering diverse detailed corrosive forms. The ASTM B31 G code has been developed as the evaluation method for reliability and incident prevention of damaged pipelines based on the amount of loss due to corrosion and the yield strength of materials. Furthermore, we suggest a method for estimating the expected life span of used pipelines by utilizing the reliability method based on major variables such as the depth and length of damage and the corrosion rate affecting the life expectancy of the pipelines.

A Study of Flow Pattern around the Two-Dimensional Dual Subsea Pipeline on Sea Bottom (해저면에 설치된 2차원 복합해저관로 주위의 유동특성에 관한 실험적 연구)

  • 나인삼;조철희;정우철;김두홍
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
    • /
    • 2001.10a
    • /
    • pp.122-127
    • /
    • 2001
  • As pipelines are often used to transport gas, oil, water and oil products, there are more than one pipeline installed in the offshore field. The size and space of pipelines are various depending on the design specifications. The pipelines are to be designed and installed to secure the stability to external loads during the installation and operation period. The flow patterns are very complex around the pipelines being dependent on incoming flow velocity, pipelines size and space. To investigate the flow patterns, number of experiment are conducted with visualization equipment in a circulating water channel. The flow motion and trajectory were recorded from the laser reflected particles by camera. From the experiment the flow patterns around spaced pipelines were obtained. Also pressure gradient was measured by mano-meter to estimate the hydrodynamic forces on the behind pipeline. The results show that the various sizes and spaces can be affected in the estimation of external load. The complex flow patterns and pressure gradients can be effectively used in the understanding of flow motion and pressure gradient.

  • PDF

Influence of ground motion spatial variations and local soil conditions on the seismic responses of buried segmented pipelines

  • Bi, Kaiming;Hao, Hong
    • Structural Engineering and Mechanics
    • /
    • v.44 no.5
    • /
    • pp.663-680
    • /
    • 2012
  • Previous major earthquakes revealed that most damage of the buried segmented pipelines occurs at the joints of the pipelines. It has been proven that the differential motions between the pipe segments are one of the primary reasons that results in the damage (Zerva et al. 1986, O'Roueke and Liu 1999). This paper studies the combined influences of ground motion spatial variations and local soil conditions on the seismic responses of buried segmented pipelines. The heterogeneous soil deposits surrounding the pipelines are assumed resting on an elastic half-space (base rock). The spatially varying base rock motions are modelled by the filtered Tajimi-Kanai power spectral density function and an empirical coherency loss function. Local site amplification effect is derived based on the one-dimensional wave propagation theory by assuming the base rock motions consist of out-of-plane SH wave or combined in-plane P and SV waves propagating into the site with an assumed incident angle. The differential axial and lateral displacements between the pipeline segments are stochastically formulated in the frequency domain. The influences of ground motion spatial variations, local soil conditions, wave incident angle and stiffness of the joint are investigated in detail. Numerical results show that ground motion spatial variations and local soil conditions can significantly influence the differential displacements between the pipeline segments.

Analysis of the induced voltage on the GAS pipelines buried in parallel with 22.9kV distribution line (22.9kV 배전선로와 병행하는 가스배관의 유도성 유도전압 해석)

  • Lee, H.G.;Ha, T.H.;Bae, J.H.;Kim, D.K.
    • Proceedings of the KIEE Conference
    • /
    • 2002.07a
    • /
    • pp.130-132
    • /
    • 2002
  • Because of the continuous growth of energy consumption and also the tendency to site power lines and pipelines along the same route, the close proximity of power lines and buried metallic pipelines has become more and more frequent. Therefore there has been and still is a slowing concern about possible hazards resulting from the influence of power lines on metallic pipelines. Underground pipelines that run parallel to or in close proximity to power lines are subjected to induced voltages caused by the time-varying magnetic fields produced by the power line currents. The induced electro- motive force cause currents circulation in the pipeline and voltages between the pipeline and surrounding earth. This paper analyzes the induced voltage on the gas pipelines buried in parallel with 22.9kV distribution lines. Their magnitude depends on the length of parallelism and on the distance between distribution lines and pipeline.

  • PDF