Pipeline Material Reliability Analysis Regarding to Probability of Failure Using Corrosion Degradation Model

Reliability of equipment of the oil and gas industry is vital, whereas on pipeline transmission system, decreasing the integrity of the pipeline is generally caused by corrosion. Failure that occurs due to corrosion deterioration influenced by the environment within a certain time, and has exceeded the nominal thickness of the pipe so there is a failure. This study used the reliability analysis approach based on modeling corrosion degradation ratio that is determined by the amount of the corrosion rate externally and internally. Using the Weibull probabilistic distribution method, results that the reliability of pipeline will decrease with increasing lifetime. It was identified that internal corrosion has a major contribution to the remaining life of pipeline. From the calculation results obtained by external corrosion has the greatest reliability over 60 years, followed by internal corrosion less than 30 years and the least is by cumulative corrosion which is less than 20 years. From the value of reliability, it can be known probability of failure (POF) which is the anti reliability.

Download Full-text

Self Directed Integrity Assessment of Non-Piggable Pipelines

ASME 2015 India International Oil and Gas Pipeline Conference ◽

10.1115/iogpc2015-7949 ◽

2015 ◽

Author(s):

Ashish Khera ◽

Rajesh Uprety ◽

Bidyut B. Baniah

Keyword(s):

Oil And Gas ◽

Oil And Gas Industry ◽

Management Plan ◽

Gas Industry ◽

Internal Corrosion ◽

Integrity Assessment ◽

Regulatory Standards ◽

The Us ◽

Integrity Management ◽

External Corrosion

The responsibility for managing an asset safely, efficiently and to optimize productivity lies solely with the pipeline operators. To achieve these objectives, operators are implementing comprehensive pipeline integrity management programs. These programs may be driven by a country’s pipeline regulator or in many cases may be “self-directed” by the pipeline operator especially in countries where pipeline regulators do not exist. A critical aspect of an operator’s Integrity Management Plan (IMP) is to evaluate the history, limitations and the key threats for each pipeline and accordingly select the most appropriate integrity tool. The guidelines for assessing piggable lines has been well documented but until recently there was not much awareness for assessment of non-piggable pipelines. A lot of these non-piggable pipelines transverse through high consequence areas and usually minimal historic records are available for these lines. To add to the risk factor, usually these lines also lack any baseline assessment. The US regulators, that is Office of Pipeline Safety had recognized the need for establishment of codes and standards for integrity assessment of all pipelines more than a decade ago. This led to comprehensive mandatory rules, standards and codes for the US pipeline operators to follow regardless of the line being piggable or non-piggable. In India the story has been a bit different. In the past few years, our governing body for development of self-regulatory standards for the Indian oil and gas industry that is Oil Industry Safety Directorate (OISD) recognized a need for development of a standard specifically for integrity assessment of non-piggable pipelines. The standard was formalized and accepted by the Indian Ministry of Petroleum in September 2013 as OISD 233. OISD 233 standard is based on assessing the time dependent threats of External Corrosion (EC) and Internal Corrosion (IC) through applying the non-intrusive techniques of “Direct Assessment”. The four-step, iterative DA (ECDA, ICDA and SCCDA) process requires the integration of data from available line histories, multiple indirect field surveys, direct examination and the subsequent post assessment of the documented results. This paper presents the case study where the Indian pipeline operators took a self-initiative and implemented DA programs for prioritizing the integrity assessment of their most critical non-piggable pipelines even before the OISD 233 standard was established. The paper also looks into the relevance of the standard to the events and other case studies following the release of OISD 233.

Download Full-text

Effectiveness of Ultraviolet Light For Mitigating Risk of Microbiologically Influenced Corrosion in Steel Pipeline

Jurnal Teknologi ◽

10.11113/jt.v74.4605 ◽

2015 ◽

Vol 74 (4) ◽

Author(s):

M. K. F. M. Ali ◽

N. Md. Noor ◽

N. Yahaya ◽

A. A. Bakar ◽

M. Ismail

Keyword(s):

Oil And Gas ◽

Oil And Gas Industry ◽

Microbiologically Influenced Corrosion ◽

Metal Loss ◽

Desulfovibrio Vulgaris ◽

Pipeline System ◽

Long Distance ◽

Gas Industry ◽

Internal Corrosion ◽

Steel Pipeline

Pipelines play an extremely important role in the transportation of gases and liquids over long distance throughout the world. Internal corrosion due to microbiologically influenced corrosion (MIC) is one of the major integrity problems in oil and gas industry and is responsible for most of the internal corrosion in transportation pipelines. The presence of microorganisms such as sulfate reducing bacteria (SRB) in pipeline system has raised deep concern within the oil and gas industry. Biocide treatment and cathodic protection are commonly used to control MIC. However, the solution is too expensive and may create environmental problems by being too corrosive. Recently, Ultraviolet (UV) as one of the benign techniques to enhance mitigation of MIC risk in pipeline system has gained interest among researchers. An amount of 100 ml of modified Baar’s medium and 5 ml of Desulfovibrio vulgaris (strain 7577) seeds was grown in 125 ml anaerobic vials with carbon steel grade API 5L-X70 coupons at the optimum temperature of 37°C and pH 9.5 for fifteen days. This was then followed by exposing the medium to UV for one hour. Results from present study showed that UV radiation has the ability to disinfect bacteria, hence minimizing the risk of metal loss due to corrosion in steel pipeline.

Download Full-text

Effect of pH in SRB (ATCC 7757) Growth for Oil and Gas API X 70 Steel Pipes

Journal of Engineering and Science Research ◽

10.26666/rmp.jesr.2019.1.4 ◽

2019 ◽

Vol 3 (1) ◽

pp. 30-36

Author(s):

Zuraini Din ◽

Keyword(s):

Carbon Steel ◽

Corrosion Rate ◽

Oil And Gas ◽

Desulfovibrio Desulfuricans ◽

Oil And Gas Industry ◽

Gas Industry ◽

Corrosion Failure ◽

Bacteria Growth ◽

Steel Pipes ◽

Metal Pipes

In the oil and gas industry, pipeline is the major transportation medium to deliver the products. According to [1] containment of pipeline loss to indicate that corrosion has been found to be the most predominant cause for failures of buried metal pipes. MIC has been identified as one of the major causes of underground pipeline corrosion failure and Sulphate Reducing Bacteria (SRB) are the main reason causing MIC, by accelerating corrosion rate. The objectives of this study is to study the SRB growth, Desulfovibrio desulfuricans ATCC 7757 due to pH and determine the optimum value controlling the bacteria growth on the internal pipe of carbon steel grade API X70. The result shows that the optimum SRB growth is at range pH 5-5 to 6.5 and the exposure time of 7 to 14 days. At pH 6.5 the maximum corrosion rate is 1.056 mm/year. Corrosion phenomena on carbon steel in the study proven had influence by pH and time. From this result pitting corrosion strongly attack at carbon steel pipe. In the future project, it is recommended to study the effect of different pipe location for example the pipeline under seawater.

Download Full-text

A Transient Approach for Estimating Concentration of Water Droplets in Oil and Corrosion Assessment in the Oil and Gas Industry

Volume 5: Multiphase Flow ◽

10.1115/ajkfluids2019-5465 ◽

2019 ◽

Author(s):

Farzin Darihaki ◽

Siamack A. Shirazi ◽

Qingshan Feng

Keyword(s):

Oil And Gas ◽

Vertical Direction ◽

Oil And Gas Industry ◽

Dispersion Modeling ◽

Water Droplets ◽

Gas Industry ◽

Pipe Surface ◽

Internal Corrosion ◽

One Dimensional ◽

System Integrity

Abstract Water-in-oil dispersion modeling is critical to assess the internal corrosion in pipelines, specifically for the oil and gas industry applications. In many oil transportation facilities, a small amount of water could be entrained in production fluids. Turbulence can break out the water into the form of tiny droplets. Under certain conditions in horizontal or inclined pipelines, water droplets can settle and contact the wall which may lead to CO2 and/or O2 or other forms of corrosion and damage the transport system integrity. In the present study, a novel transient approach has been developed that provides water concentrations across the pipe section. A one-dimensional transient finite-difference computational model has been used to determine concentration distribution in a vertical direction across the pipe. Calculated water fractions using the transient model is compared to experimental data and more comprehensive 3-D Computational Fluid Dynamics (CFD) approach for various flow conditions and watercuts that shows the viability of the simplified one-dimensional approach. The proposed model is capable of predicting water dispersion at different locations and could be utilized for various pipe-flow systems. Furthermore, water in the form of droplets or liquid film can result in corrosion when it wets the pipeline surface. Consequently, the calculated water concentration at the bottom of the pipe assists in determining wettability of the pipe surface by water and evaluating the corrosion risk along the pipeline.

Download Full-text

Magnetic Internal Corrosion Detection Sensor for Exposed Oil Storage Tanks

Sensors ◽

10.3390/s21072457 ◽

2021 ◽

Vol 21 (7) ◽

pp. 2457

Author(s):

Ahmad Aljarah ◽

Nader Vahdati ◽

Haider Butt

Keyword(s):

Oil And Gas ◽

Experimental Testing ◽

Oil And Gas Industry ◽

Metal Loss ◽

Storage Tanks ◽

Gas Industry ◽

Internal Corrosion ◽

Detection Range ◽

Corrosion Detection ◽

Oil Storage

Corrosion in the oil and gas industry represents one of the major problems that affect oil production and transportation processes. Several corrosion-inspection technologies are in the market to detect internal and external corrosion of oil storage tanks, but inspection of storage tanks occurs every 3 to 7 years. In between inspection interval, aggressive corrosion can potentially occur, which makes the oil and gas industry vulnerable to accidents. This study proposes a new internal corrosion detection sensor based on the magnetic interaction between a rare-earth permanent magnet and the ferromagnetic nature of steel, used to manufacture oil storage tanks. Finite element analysis (FEA) software was used to analyze the effect of various sensor parameters on the attractive force between the magnet and the steel. The corrosion detection sensor is designed based on the FEA results. The experimental testing of the sensor shows that it is capable of detecting internal metal loss due to corrosion in oil storage tanks within approximately 8 mm of the internal surface thickness. The sensor showed more than two-fold improvement in the detection range compared to previous sensor proposed by the authors. Furthermore, the sensor of this paper provides a monitoring rather than occasional inspection solution.

Download Full-text

Assessment of Offshore Piping Composite Repair Technology for Life Extension Program Case in Pertamina Hulu Energy West Madura Offshore

MATEC Web of Conferences ◽

10.1051/matecconf/201926906005 ◽

2019 ◽

Vol 269 ◽

pp. 06005

Author(s):

Muhamad Arifin ◽

Arif Cahyono ◽

Idam Putra ◽

Badrul Munir

Keyword(s):

Oil And Gas ◽

Good Condition ◽

Oil And Gas Industry ◽

Life Extension ◽

Process Safety ◽

Pressure System ◽

Gas Industry ◽

Composite Repair ◽

External Corrosion ◽

Extension Program

The pipe work repair method such as clamps and pipe connector as the use of metallic repair component have been used for maintenance and repair application in oil and gas industry and cover the most common types of defect to pressurize system like internal and external corrosion and also cover situations where the damage is severe. On the other hand with a process safety precausion and production concern, in oil and gas facility the use of metallic repair is very challenging and most of the time will come as last option scenario. Composite repair which are now increasing in application to pipe repair situations may come as a solution. This paper provides assessment of offshore piping composite repair for life extension program of pressure system in West Madura Offshore. Assessment come to a conclusion that the composite repair at field PHE WMO which operate on envelop of 700 psi and temperature range of 20°C-80°C are still in good condition and retain the integrity of the asset, from where then the repair is considered to extent its lifetime.

Download Full-text

Lazy-Wave Buoyancy Length Reduction Based on Fatigue Reliability Analysis

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.4038937 ◽

2018 ◽

Vol 140 (3) ◽

Author(s):

Vinícius Ribeiro Machado da Silva ◽

Luis V. S. Sagrilo ◽

Mario Alfredo Vignoles

Keyword(s):

Reliability Analysis ◽

Cost Reduction ◽

Structural Reliability ◽

Oil And Gas ◽

Oil And Gas Industry ◽

Fatigue Reliability ◽

Gas Industry ◽

Deep Waters ◽

Sea Bed ◽

Length Reduction

The current downturn of the oil and gas industry force managers to take hard decisions about the continuity of projects, resulting in delays, postponements, or even their cancellation. In order to keep with them, the rush for cost reduction is a reality and the industry is pushing the involved parties to be aligned with this objective. The Brazilian presalt region, characterized by ultra-deep waters, faces this scenario where flexible risers in lazy-wave configurations are usually adopted as a solution to safe transfer fluids from sea bed until the floating unit. The smaller the buoyancy length, the cheaper the project becomes, reducing the necessary amount of buoys and the time spent for its installation. This paper investigates the possibility of buoyancy length reduction of lazy-wave configurations by using structural reliability methods on fatigue failure mode. The application of the fatigue reliability approach considers four 6 in flexible riser configurations: an original lazy-wave, a lazy-wave with less 30% of buoyancy length, another one with less 50% of buoyancy length and a free-hanging. Failure probabilities and safety factor calibration curves are shown for each configuration and compared among themselves. The results indicate the possibility of defining a lazy-wave configuration with smaller buoyancy lengths, reaching 75% of reduction without changing the preconized high safety class. Structural reliability analysis is available to help engineers understand the driving random variables of the problem, supporting the actual scenario of cost reduction for better decision-making based on quantified risk.

Download Full-text