Resourceful and Promising Leader of Pipeline Engineering

Dong Xu’s parents are both employees of the China Petroleum Pipeline Bureau.Therefore,it was wellreasoned for him to study in petroleum colleges and universities and work in the China Petroleum Pipeline Bureau.It never occurred to him that he could not work as a pipeline worker.Over the past 34 years,Dong Xu’s understanding of himself has changed from a“pipeline worker”to a“leader of pipeline engineering”,which proved the sublimation of his emotion to the pipeline when his role was changed from a spectator to participant and from a worker to a leader.

Development and Prospects of Large-Scale Underground Oil(Gas)Storage Technology in China

As a major source of energy in the world today,the state of oil reserves has become an important indicator of a country’s strength.Many countries,including China,are actively increasing energy reserves to cope with increasingly severe geopolitical risks and international market risks.This article provides an introduction to the international energy landscape,highlighting the progress made in energy reserves both domestically and globally.It places particular emphasis on China’s underground oil(gas)storage technology,discussing its current status and future prospects.Furthermore,the article anticipates the advancements expected in oil storage,gas storage,hydrogen storage,and other related technologies.

Advancing Internationalization:Actively Pursuing a Shared Vision-An Examination of CPP’s Dynamic Involvement in the Belt and Road Initiative

On September 7,2013,President Xi Jinping proposed the significant initiative of jointly building the Silk Road Economic Belt.On October 3,2013,President Xi proposed the major initiative of jointly building the 21st Century Maritime Silk Road.Since its inception in the autumn of 2013,the Belt and Road initiative,envisioned as a monumental project carrying the mission of the era,has turned a new page in the global development process.Over the past 11 years,China Petroleum Pipeline Engineering Co.,Ltd.(CPP)has thoroughly implemented the strategic deployment of China National Petroleum Corporation(CNPC),actively fulfilled its corporate responsibilities,and embraced high-quality participation in the Belt and Road Initiative as its mission.By fully leveraging its international advantages,CPP has continuously contributed“pipeline strength”to the high-quality joint construction of the Belt and Road.

A Study on Inhibitors for the Prevention of Hydrate Formation in Gas Transmission Pipeline

Gas Hydrate is usually formed during the transportation and treatment of oil and gas, resulting in the plugging of gas pipeline and equipment. Three thermodynamic calculation formulas are analyzed to deal with this problem. The lowering of the freezing point of the inhibitors △T is used to calculate the formation temperature of natural gas hydrates. This is considered to be a good approach because it is not limited by what kind and what concentration of inhibitors one uses. Besides, the rate of lowering of the freezing point could be easily measured. The result of testing methanol and mono-ethylene glycol in a reactor shows that adding 10% inhibitors to the reactor can prevent the hydrates formation. Kinetic inhibitors are favored in the present research. They are divided into two types, polymer and surface-active agents. Their characteristics, mechanisms, and application prospect are separately discussed. Polymer inhibitors exhibit better efficiency. The result of field application of VC-713 inhibiter is also given in this article. In practice, the combination of thermodynamic inhibitors and kinetic inhibitors gives better result.

Research on laser-arc hybrid welding technology for long-distance pipeline construction

In recent years, the research on pipeline laser-arc hybrid welding technology has been the important and difficult in the field of welding all over the world. China Petroleum Pipeline Research Institute Co. Ltd. has firstly developed pipeline laser-arc hybrid welding system in China, and executed the welding tests based on X70/X80 steel. Preliminary experiment results showed that hybrid welding could meet the requirements of related standards such as API1104,ASME,etc., the mechanical properties of girth seam are qualified in the case that there were no internal defects. With the development of high-power fiber laser and the continuous improvement of welding equipment, laser-arc hybrid welding technology for pipeline field welding will be available soon.

Prediction of Collapse Pressure of Submarine Pipelines in A Wide Range of Diameter–Thickness Ratio

Submarine pipelines play an important role in offshore oil and gas development.A touchy issue in pipeline design and application is how to avoid the local collapse of pipelines under external pressure.The pipe diameter-thickness ratio D/t is one of the key factors that determine the local critical collapse pressure of the submarine pipelines.Based on the pipeline collapse experiment and finite element simulation,this paper explores the pressure-bearing capacity of the pipeline under external pressure in a wide range of diameter-thickness ratio D/t.Some interesting and important phenomena have been observed and discussed.In the range of 16<D/t<80,both DNV specification and finite element simulation can predict the collapse pressure of pipeline quite well;in the range of 10<D/t<16,the DNV specification is conservative compared with the experimental results,while the finite element simulation results are slightly larger than the experimental results.Further parameter analysis shows that compared with thin-walled pipes,improving the material grade of thick-walled pipes has higher benefits,and for thin-walled pipes,the ovality f_(0)should be controlled even more.In addition,combining the results of finite element simulation and model experiment,an empirical formula of critical collapse pressure for thick-walled pipelines is proposed,which is used to correct the error of DNV specification in the range of 10<D/t<16.

Research on low carbon emission optimization operation technology of natural gas pipeline under multi-energy structure

In order to reduce the carbon emissions of natural gas pipelines,based on the background of different energy structures,this paper proposes a general low carbon and low consumption operation model of natural gas pipelines,which is used to fine calculate the carbon emissions and energy consumption of natural gas pipeline.In this paper,an improved particle swarm optimization(NHPSO-JTVAC)algorithm is used to solve the model and the optimal scheduling scheme is given.Taking a parallel pipeline located in western China as an example,the case is analyzed.The results show that after optimization,under the existing energy types,the pipeline system can reduce 31.14%of carbon emissions,and after introducing part of new energy,the pipeline system can reduce 34.02%of carbon emissions,but the energy consumption has increased.

A successful case of hydrocarbon dew point analysis during mixing of natural gases in transmission pipeline

The occurrence of liquid condensation in natural gas accounts for new challenges during the interoperability between transmission networks,where condensation would lead to higher pressure drops,lower line capacity and may cause safety problem.A successful case of hydrocarbon dew point(HCDP)analysis is demonstrated during the mixing of natural gases in the transmission pipeline.Methods used to predict the HCDP are combined with equations of state(EOS)and characterization of C6+heavy components.Predictions are compared with measured HCDP with different concentrations of mixed gases at a wide range of pressure and temperature scopes.Software named"PipeGasAnalysis"is developed and helps to systematic analyze the condensation problem,which will provide the guidance for the design and operation of the network.

Reliability analysis of large-diameter high-grade-steel natural gas pipelines under fault action

There are a lot of researches on qualitative aseismatic measures for buried gas pipeline crossing movable faults.But a few of them are quantitative,especially in the size and shape of the trench.The paper first established the finite element model of the strain of buried pipeline crossing a fault which effected by the size and shape of the trench.And it obtained new soil spring stiffness which considered different buried depth,bottom width of trench,trench slope and elastic modulus of soil.The mechanical analysis model of pipeline is established,and the limit state equation of pipeline is fitted.The reliability and sensitivity of the natural gas pipeline under fault action are analysed by a Monte Carlo method,and the error and accuracy are verified.When the pipeline is under tension,the sensitivity from large to small is buried depth,sand friction angle,pipe diameter,pipeline displacement,trench bottom width,trench depth,clay cohesion,trench slope and clay friction angle;when the pipeline is under pressure,the trench depth and clay cohesion have great influence.The findings of this study provide a reference for pipeline design and safety evaluation under fault action.

Research on Human Resources Localization for Overseas Pipeline Projects-Taking the Indian Project as an Example

Given fierce competition in the overseas pipeline project market, human resources localization has become the only way to sustain the development of overseas pipeline projects. Thus, in this paper, the significance of human resources localization is analyzed in terms of the needs of the "going global" strategy, the reduction of labor costs, the aversion of project risks, and project communication. In addition, relevant measures for human resources localization are proposed, taking the Indian project as an example.

材料特性对输送脉动流体的粘弹性轴向功能梯度管非线性动力行为的影响

The nonlinear dynamic behaviors of viscoelastic axially functionally graded material(AFG)pipes conveying pulsating internal flow are very complex.And the dynamic behavior will induce the failure of the pipes,and research of vibration and stability of pipes becomes a major concern.Considering that the elastic modulus,density,and coefficient of viscoelastic damping of the pipe material vary along the axial direction,the transverse vibration equation of the viscoelastic AFG pipe conveying pulsating fluid is established based on the Euler-Bernoulli beam theory.The generalized integral transform technique(GITT)is used to transform the governing fourth-order partial differential equation into a nonlinear system of fourth-order ordinary differential equations in time.The time domain diagram,phase portraits,Poincarémap and power spectra diagram at different dimensionless pulsation frequencies,are discussed in detail,showing the characteristics of chaotic,periodic,and quasi-periodic motion.The results show that the distributions of the elastic modulus,density,and coefficient of viscoelastic damping have significant effects on the nonlinear dynamic behavior of the viscoelastic AFG pipes.With the increase of the material property coefficient k,the transition between chaotic,periodic,and quasi-periodic motion occurs,especially in the high-frequency region of the flow pulsation.

Two-Stage Optimal Dispatching of Wind Power-Photovoltaic-Solar Thermal Combined System Considering Economic Optimality and Fairness

Aiming at the problems of large-scale wind and solar grid connection,how to ensure the economy of system operation and how to realize fair scheduling between new energy power stations,a two-stage optimal dispatching model of wind power-photovoltaic-solar thermal combined system considering economic optimality and fairness is proposed.Firstly,the first stage dispatching model takes the overall economy optimization of the system as the goal and the principle of maximizing the consumption of wind and solar output,obtains the optimal output value under the economic conditions of each new energy station,and then obtains the maximum consumption space of the new energy station.Secondly,based on the optimization results of the first stage,the second stage dispatching model uses the dispatching method of fuzzy comprehensive ranking priority to prioritize the new energy stations,and then makes a fair allocation to the dispatching of the wind and solar stations.Finally,the analysis of a specific example shows that themodel can take into account the fairness of active power distribution of new energy stations on the basis of ensuring the economy of system operation,make full use of the consumption space,and realize the medium and long-term fairness distribution of dispatching plan.

Hydroisomerization of n-Pentane over Zn-Fe-S2O8-2/ZrO2-Al2O3 Superacid Catalyst: Activity, Surface Analysis and the Investigation of Deactivation and Regeneration

The Zn and Fe modified /ZrO2-Al2O3 catalyst (Zn-Fe-SZA) was prepared and mechanisms of deactivation and methods for regeneration of as-prepared catalyst were explored with n-pentane isomerization as a probe reaction. The results indicated that the isopentane yield of the fresh Zn-Fe-SZA-F catalyst was about 57% at the beginning of the run, and declined gradually to 50% within 1500 min, then fell rapidly from 50% to 40% between 1500 and 2500 minutes. The deactivation of Zn-Fe-SZA catalyst may be caused by carbon formation on surface of the catalyst, sulfate group attenuation owing to reduction by hydrogen, removal of sulfur species and the loss of strong acid sites. It was found that the initial catalytic activity over Zn-Fe-SZA-T catalyst was 48%, which recovered by 84.3% as compared to that of fresh catalyst (57%). However, it showed a sharp decrease in isopentane yield from 48% to 29% within 1500 minutes, showing poor stability. This is associated to the loss of acidity caused by removal of sulfur species cannot be basically restored by thermal treatment. Resulfating the calcined catalyst could improve the acidity of catalyst significantly, especially strong acid sites, as compared with the calcined sample. The improved stability of the resulfated catalyst can be explained by: 1) eliminaton of carbon deposition to some extent by calcination process, 2) formation of improved acidic nature by re-sulfation, favoring isomerization on acidic sites, 3) restructuring of the acid and metal sites via the calcination-re-sulfation procedure.

Research on physical explosion crater model of high-pressure natural gas pipeline

In this study,Hypermesh and LS-DYNA numerical simulation software are used to build a multi domain coupling model of natural gas pipeline,including soil,pipeline,TNT explosive and air domain,and the non-reflection boundary conditions are set for the model.The TNT equivalent method is used to convert the physical explosion amount of natural gas pipeline into 1387.38 kg TNT explosive amount.The simulation results show that the physical explosion of pipeline forms an approximate elliptical crater with a width of 12.68 m and a depth of 4.12 m;the TNT equivalent of the model is corrected by comparing the crater simulation value and the size value of the crater calculated by the PRCI empirical formula under the same laying condition,and the correction coefficient is selected as O.9,and the cor-rected TNT equivalent is 1248.64 kg:the modified model crater size is 3.72 m deep and 12.66 m wide,compared with the crater size obtained from the field test,the error of crater depth and width calculated by the modified model simulation is 5.7%and 15.5%respectively.

Formation and evolution of the tertiary carbonate reefs in the Madura Strait Basin of Indonesia

Analysis of 2 D seismic data over 4 500 km in length from the Madura Strait Basin in the East Java Sea reveals seismic re?ection characteristics of reefs and associated sedimentary bodies, including asymmetrical or symmetrical dome re?ections, slope progradational re?ections, chaotic re?ections and discontinuous strong re?ections inside the reef, which onlap the ?ank of the reef. It is concluded that the developmental paleo-environment of most reefs is mainly conducive to shallow marine carbonate platform facies and platform margin facies, based on well core data, variations in seismic facies and strata thickness.The formation and evolution of all reefs are primarily in?uenced by the tectonic framework of the Madura Strait Basin. Platform margin reefs are principally controlled by two types of structures: one is a series of E-W trending Paleogene normal faults, and the other is an E-W trending Neogene inversion structures. In addition, wave actions, tidal currents and other ocean currents play an accelerated role in sorting, rounding and redeposition for the accumulation and evolution of reefs. Tertiary reefs in the MSB can be divided into four types: 1) an open platform coral reef of Late Oligocene to Early Miocene, 2) a platform margin coral reef controlled by normal faults in Late Oligocene to Early Miocene, 3) a platform margin Globigerina moundreef controlled by a "hidden" inversion structure in Early Pliocene, and 4) a platform margin Globigerina mound-reef controlled by thrust faults in the early Pliocene. Patterns of the formation and evolution of reefs are also suggested.

An early warning method for water inrush in Dongjiahe coal mine based on microseismic moment tensor

Dongjiahe Coal Mine belongs to the Carboniferous Permian coal field which has a high degree of karst and fissure development.This paper takes the working face of Dongjiahe Coal Mine as an example;through the microseismic(MS)monitoring system arranged on the working face,the moment tensor theory was used to invert the focal mechanism solution of the anomalous area of the floor MS event;combining the numerical simulation and field data,the underlying floor faults were identified by the stress inversion method.The results show that:1)Moment tensors were decomposed into three components and the main type of rupture in this area is mixed failure according to the relative criterion;2)The hidden fault belongs to the reversed fault,its dip angle is approximately 70°,and the rupture length is 21 m determined by the inversion method of the initial dynamic polarity and stress in the focal mechanism;3)The failure process of the fault is divided into three stages by numerical simulation method combined with the temporal and spatial distribution of MS events.The results can provide a reference for early warning and evaluation of similar coal mine water inrush risks.

Strength mismatch mechanism on friction stir welding joint of 7075 aluminum alloy

The precipitated phases in the WNZ,TMAZ,HAZ and BM of the friction stir welding(FSW)joint were observed using the transmission electron microscopy(TEM)and the lattice fringe spacing of the precipitated phases was measured.Combined with X-ray diffraction(XRD),the types of precipitated phases among the joint were confirmed and then the strength mismatch mechanism was revealed.The results show the precipitated phases of 7075 aluminum alloy FSW joint mainly consist of MgZn_(2),AlCuMg and Al_(2)CuMg.The microzone of the joint experienced different thermal cycles,the types and sizes of precipitated phases are different and the strengthening effect is different.The strengthening effect of the AlCuMg and Al_(2)CuMg are better than that of MgZn_(2).The precipitated phase in the WNZ mainly includes AlCuMg and Al_(2)CuMg,as well as the grain size is fine,the microhardness in this zone is pretty high.The number of precipitated phase AlCuMg and Al_(2)CuMg is smaller in the TMAZ and the MgZn_(2)is relatively more,which lead the microhardness decrease.The number of precipitated phase MgZn_(2)is relative larger in the HAZ,as well as the grain coarsening,the microhardness in this zone is lowest of the joint.At the same time,there are the precipitate free zones(PFZ)among the 7075 aluminum alloy FSW joint,which decreases the microhardness of the whole joint to some extent.

Study of Structural Parameters of the Inlet of Downhole Hydrocyclones

Three different inlets of hydrocyclone are studied in combination with the construction of a dowrahole system and hydrocyclone. By comparing the relationship between the inlet structure ＆ dimensional parameter of hydrocyclone and separation efficiency ＆ pressure loss, the highest efficiency is obtained from the inlet of an involute curve with increasing depth-width ratio from the three types, in which the separation efficiency and pressure loss all drops slowly, for the length of the channel decreases, while it drops rapidly in the other two. The flow guiding ability of the inlet affects the separation efficiency greatly, so the corresponding involute type of inlet of hydrocyclone fits for downhole oil-water separation is optimized, which serves as a basis for the structural design of downhole hydrocyclone.

Thermal simulation of single thermal cycle for high strength steel pipe

Single thermal cycle simulation tests were carried out for X80 high strength steel pipes from three steel mills by a Gleeble 3500HS thermal simulation test machine,and coincidence degree of the thermal simulation curve with the set curve under heat inputs of 6–30 kJ/cm was observed;The relationship between different heat inputs and microstructure,impact toughness and hardness of steel pipe CGHAZ(coarse grain heat affected zone)was studied by metallographic examination,impact test and hardness test.The results show that with the increase of heat input,original austenite grain size increases gradually,the lath bainite ratio decreases and the granular bainite ratio increases.The impact toughness of C steel pipe is lower than those of A and B steel pipe,and the impact toughness of CGHAZ from the three steel pipes show different trends:for A steel pipe CGHAZ,impact toughness increases first and then decreases,with the highest value of 270–320 J under 20–25 kJ/cm;for B steel pipe CGHAZ,impact toughness decreases slightly;for C steel pipe CGHAZ,impact toughness increases,with the highest value of 260–300 J under 25 kJ/cm.As the heat input increases,the hardness of three X80 steel pipes CGHAZ shows a decreasing trhighend,and C steel pipe has the largest decreasing range.

Rheological numerical simulation for thermo-hydro-mechanical coupling analysis for rock mass

Under the environment of seepage field, stress field and temperature field interaction and influence, the three fields will not only produce coupling effect, but also have deformation with time due to the rheological behavior of rock mass. In the paper, based on the fundamental theories of rock mass coupling theory and rheological mechanics, the rheological model for fully coupled thermo-hydro-mechanical analysis for rock mass was set up, and the corresponding constitutive relationship, the conservation equation of mass and the conservation equation of energy were given, and the finite element formulas were derived for coupling analysis of rock mass. During establishing governing equations, rock mass was assumed approximately as macro-equivalent continuum medium. The obtained rheological numerical model for fully coupled thermo-hydro-mechanical analysis can be used for analyzing and predicting the long-term stability of underground caverns and slope engineering under the condition of thermo-hydro-mechanical coupling with rheological deformation.