Integrity of Small Angle Mitered Joints

2016 ◽  
Author(s):  
Gavin (Guowei) Zheng ◽  
Iain Colquhoun ◽  
Joe Paviglianiti
Keyword(s):  
Sensitivity Analysis ◽  
Small Angle ◽  
Thermal Loading ◽  
Oil And Gas ◽  
Strong Dependence ◽  
Oil And Gas Industry ◽  
Gas Pipeline ◽  
Theoretical Development ◽  
Gas Industry ◽  
Cyclic Service

Miter bends are permitted for use in the oil and gas industry in a variety of configurations. This paper addresses small angle miter joints used to correct minor misalignments. The CSA Z662-15 standard (Oil and Gas Pipeline Systems) states in the construction section (Clause 6.2.3(g)) that “mitred bends shall not be used”. However, a note accompanying the clause states that “deflections up to 3 degrees caused by misalignment are not considered to be mitred bends.” Nonetheless, concerns continue to be raised that stresses introduced due to this misalignment can affect safety and operation of pipelines. This paper reviews literature of failures associated with mitered joints and the theoretical development of stresses in miters, and presents results from a linearized sensitivity analysis of buried mitered joints under pressure and thermal loading based on ASME B31.1 and B31.3 criteria. The paper contains an analysis of the origins of CSA-Z662 Clause 6.2.3(g). Recognizing that the stresses introduced by miters are discontinuity stresses, the paper discusses the effects of such stresses, including the use of miters in cyclic service. Recognizing also the strong dependence of D/t ratio on the discontinuity stress, the paper suggests a modification to the Z662 approach to account for this effect. This modification would provide guidance to the use of miters to effect small deflections both during design and construction of piping.

What Does Rent Give to Federal Budget (on the Russia's Budget Dependence upon "Oil Dollars")

2004 ◽  
pp. 51-69 ◽  
Author(s):  
E. Sharipova ◽  
I. Tcherkashin
Keyword(s):  
Oil And Gas ◽  
Strong Dependence ◽  
Oil Prices ◽  
Federal Budget ◽  
Oil And Gas Industry ◽  
Gas Industry ◽  
Resource Rent ◽  
Tax Legislation ◽  
Russian Economy ◽  
The Government

Federal tax revenues from the main sectors of the Russian economy after the 1998 crisis are examined in the article. Authors present the structure of revenues from these sectors by main taxes for 1999-2003 and prospects for 2004. Emphasis is given to an increasing dependence of budget on revenues from oil and gas industries. The share of proceeds from these sectors has reached 1/3 of total federal revenues. To explain this fact world oil prices dynamics and changes in tax legislation in Russia are considered. Empirical results show strong dependence of budget revenues on oil prices. The analysis of changes in tax legislation in oil and gas industry shows that the government has managed to redistribute resource rent in favor of the state.

Pitting and CO2 corrosion behavior of oil and gas pipeline welds

2021 ◽  
Vol 63 (11) ◽  
pp. 1018-1024
Author(s):  
Huan Xie ◽  
Xiang Chen ◽  
Yongxin Lu ◽  
Qian Zhang ◽  
Haitao Wang
Keyword(s):  
Corrosion Behavior ◽  
Oil And Gas ◽  
Welded Joint ◽  
Oil And Gas Industry ◽  
Gas Pipeline ◽  
Co2 Corrosion ◽  
Fe Model ◽  
Gas Industry ◽  
Remaining Service Life ◽  
Pit Depth

Abstract A finite element (FE) model is presented in this work that is used to analyze the effect of pitting corrosion on the CO2 corrosion behavior of oil and gas pipeline welds. The FE model contains two parts, i. e., stress calculation of the welded joint using Abaqus software, and of the chemical reaction at the welded joint using COMSOL Multiphysics® software. The effect of transportation pressure, pit depth and welding material on the CO2 corrosion behavior of weld metal was investigated using the FE model. It turned out that the FE model is helpful to instruct the management and to assess the remaining service life prediction of pipelines in the oil and gas industry.

scholarly journals Inlet pressure simulation of pigging in uphill gas pipeline

2019 ◽  
Vol 20 (4) ◽  
pp. 406 ◽  
Author(s):  
Honggang He ◽  
Zheng Liang ◽  
Yishan Guo
Keyword(s):  
Gas Flow ◽  
Oil And Gas ◽  
Pressure Rise ◽  
Oil And Gas Industry ◽  
Gas Pipeline ◽  
Inlet Pressure ◽  
Gas Industry ◽  
Flow Equations ◽  
Pipeline Inspection ◽  
Common Operation

Pipe cleaning is a common operation in the oil and gas industry. In this paper, the governing equation of the pipeline inspection gauge (PIG, lowercase pig is commonly used) speed is combined with the gas flow equations. The method of characteristics (MOC) is used to solve the transient equations of gas flow. And the process of a pig passing over an uphill section of a gas pipeline is simulated. The results indicate that a pig may get stuck in uphill gas pipeline, due to the coupling of the gas and the pig. Under these circumstances, a higher pressure of the upstream could be helpful for driving the pig in motion. Additionally, the ratio of inlet pressure rise during the pigging process is primarily determined by the inclination of the uphill section. In addition, a formula to predict the inlet pressure during pigging in an uphill pipe is presented. Furthermore, the proposed method and solution can be utilized to predict the speed and position of the pig, as well as the gas pressure and the stoppage of the pig in hilly gas pipelines.

Investigation of the Hydrogen Stratification of the Metal of the Active Gas Pipeline

2018 ◽  
Vol 284 ◽  
pp. 1302-1306 ◽  
Author(s):  
O.A. Nasibullina ◽  
A.G. Gareev ◽  
Rif G. Rizvanov
Keyword(s):  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Gas Pipeline ◽  
Negative Effects ◽  
Local Zone ◽  
Gas Industry ◽  
Hydrogen Corrosion ◽  
Metal Structures ◽  
Metal Microstructure ◽  
Free Metal

One of the most common types of metal destruction in the oil and gas industry is hydrogen embrittlement. Hydrogen corrosion is a complex of negative effects of hydrogen on steel, leading to the destruction of metal structures. Hydrogen passes through a defect-free metal, without lingering in it. In the presence of defects, hydrogen is retained in the metal forming a brittle solid solution, metal stratification along the segregation streamer, blistering. Studies of the metal of a gas pipeline made of steel 09G2S are presented in the article. The sample was selected from the local zone of destruction in the condensate collector, the metal of the pipe had typical for hydrogen corrosion stratifications. The scope of the study was identification of the most dangerous part of hydrogen corrosion on the sample taken from the local zone of destruction. Studies on the chemical composition and mechanical properties of 09G2S steel were also carried out. Stress-related characteristics of the metal microstructure of the failed gas pipeline were obtained and the character of the destruction progress was revealed. The presence of sulfides cluster in the metal of studied pipe was determined applying metallographic method for determining nonmetallic inclusions.

scholarly journals Speed Simulation of Pig Restarting from Stoppage in Gas Pipeline

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Honggang He ◽  
Zheng Liang
Keyword(s):  
High Speed ◽  
Gas Flow ◽  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Pressure Change ◽  
Gas Pipeline ◽  
Maximum Speed ◽  
Gas Industry ◽  
Pipeline Inspection ◽  
Common Operation

Pigging is a common operation in the oil and gas industry. Because of the compressibility of the gas, starting up a pipeline inspection gauge (pig) from a stoppage can generate a very high speed of the pig, which is dangerous to the pipe and the pig itself. Understanding the maximum speed a pig achieves in the restarting process would contribute to pig design and safe pigging. This paper presents the modeling of a pig restarting from a stoppage in gas pipeline. In the model, the transient equations of gas flow are solved by method of characteristics (MOC). Runge-Kutta method is used for solving the pig speed equation. The process of a pig restarting from a stoppage in a horizontal gas pipe is simulated. The results indicate that the maximum speed a pig achieves from a stoppage is primarily determined by the pressure of the pipe and the pressure change caused by the obstructions. Furthermore, response surface methodology (RSM) is used to study the maximum speed of pig. An empirical formula is present to predict the maximum speed of a pig restarting from a stoppage in gas pipeline.

scholarly journals TARGETLESS PHOTOGRAMMETRY NETWORK SIMULATION FOR INSPECTION PLANNING IN OIL AND GAS INDUSTRY

2020 ◽  
Vol V-1-2020 ◽  
pp. 285-291
Author(s):  
P. Buschinelli ◽  
J. D. Salazar ◽  
D. Regner ◽  
D. Oliveira ◽  
M. Machado ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Low Cost ◽  
Image Acquisition ◽  
Strong Dependence ◽  
Oil And Gas Industry ◽  
Inspection Planning ◽  
Gas Industry ◽  
Remotely Piloted Aircraft ◽  
Close Range ◽  
Offshore Industry

Abstract. The oil and gas offshore industry demands regular inspections of components and structures that are subjected to extreme operational and environmental conditions. In this context, risers are pipelines that transport mainly oil, gas, water, and cables between submarine structures and the surface offshore platform, in the portion not touching the ocean floor. The emerged part of these risers is typically inspected by industrial climbing, which is a very time-consuming activity, has high operational costs, is dangerous and has a strong dependence on inspector skills. Remotely Piloted Aircraft Systems (RPAS) have been recently used for visual inspection of risers, however, no quantitative or geometrical evaluation has been conducted using this kind of image acquisition yet. An image-based measurement technique, such as close-range photogrammetry, can provide a 3D reconstruction using images, but a series of requisites is mandatory to achieve good results as image acquisition sequence, overlap, camera positioning network, spatial resolution and object texture in non-prepared and targetless scenes. The analysis of different image acquisition strategies using a real RPAS is too difficult because it demands a lot of time, good weather, daylight, and a scene similar to where risers are installed. An alternative is to use simulation. In this paper a ROS/Gazebo simulation is described and used to create a realistic textured 3D virtual environment of the platform, risers and RPA, providing a fast and low-cost solution to simulate different RPA trajectories for photogrammetry image acquisition in targetless scenes. These trajectories are evaluated by comparing the measured risers through photogrammetry to its CAD/simulated model. Since the scene is not prepared, the RPA position/orientation or a stereo vision setup can be used to set scale to the measurement result. The best trajectory found during simulations was also evaluated in a real experiment.

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