Reputation loss framework for consequence assessment of onshore pipeline damage

Consequence assessment for pipeline damage is exercised to determine the losses of a failure event such as human, asset, production and environmental loss. However, assessment of reputation loss, which is part of failure impact, is usually excluded due to its qualitative nature. Therefore, the need for a quantitative model of reputation loss is of great interest among pipeline risk assessors. The available current model assesses reputation loss qualitatively; it is a self-centered assessment, time-independent loss factors and internal stakeholder’s influence are typically neglected. Therefore, the study aimed to develop a quantitative model to quantify reputation loss of the pipeline owner in order to improve the calculation of risk of pipeline damage according to the four different stakeholders’ perceptions. A total of 30 reputation loss factors were identified via 30 case studies related to onshore pipeline damage accident reports. These factors were included in a structured online survey which was designed for the stakeholders in Malaysia to rank the factors according to its influence on owner’s reputation based on a given imaginary worst case scenario. A total of 200 respondents participated in the survey and the ranking of the factors based on the four different stakeholders were obtained. All stakeholders were in agreement that the factor which most influences the loss of owner reputation is factor D3 “Accident Severity”. It is the parent factor of D31 “Multiple fatality and injuries”, D32 “Fire extinguished in longer duration”, D33 “Destroyed private properties”, and D34 “Damaged of vast environment area”. Statistical analysis and fuzzy analytic hierarchy process (FAHP) were implemented to prioritize and weigh the factors according to the four different stakeholders’ preferences. Four reputation loss models were then proposed to predict the reputation loss due to pipeline explosion. Eight experts from PETRONAS Gas Berhad (PGB) with 15 years of experience in pipeline integrity management were selected for model validation. Model development was presented to the experts for validation survey. The result indicates that this model is considered as comprehensive, fulfilled the objective, well-defined and practical to be used with a moderate level of overall reliability which can be improved by utilizing the model in a real case study. Thus, the proposed model was implemented in a case study of pipeline in Malaysia by taking the 2014 explosion event occurred in Lawas, Sarawak as a benchmark. The value of consequence of failure calculated by the proposed model was 7% lower than the current model from PETRONAS Technical Standard. This reduction has significantly shifted the risk of pipeline failure from “High” to “Moderate” for the rural area. To conclude, the inclusion of the proposed reputation loss model may produce a comprehensive consequence assessment of pipeline damage and provide a higher level of confidence to the pipeline owner to optimize their risk-based inspection and maintenance scheme, hence, prolonging the long-term integrity of their pipeline assets and simultaneously securing the company annual profit margins

Prioritization of Reputation Loss Factors Imposed By Pipeline Failure Subject to Corrosion

Reputation loss of a pipeline failure subject to corrosion is commonly neglected due to its qualitative nature. However, case studies found that perceptions of the stakeholders are prone to affect pipeline owner’s long-term reputation. Identifying the influence factors is insufficient to assist the owner to respond if pipeline failure occurs. Thus, this article endeavors to prioritize the influential reputation loss factors by interviewing six experts of pipeline integrity management personnel. The analytic hierarchy process multi-criteria decision making method was selected to help the prioritization process. Result shows that the most influenced factor is the loss of customer confidence (B1) and employee(s) caused accident (C9) ranked the least. The effort to quantify reputation loss can be substituted by prioritizing them according to stakeholders’ preferences as an initial step to monetarily quantify these factors in future. Thus, a comprehensive pipeline risk assessment and the pipeline integrity management can be achieved and simultaneously improve the company’s annual profit margin

Linear-elastic stress field of notched concrete beam: An application of finite element in theory of critical distances

Fatigue failures occur in all structures including brittle and ductile structures. However, the study on fatigue in ductile material like metal and steel has tremendously developed compared to brittle material such as concrete. Fortunately, the Theory of Critical Distance (TCD) is witnessed successfully assess fatigue fracture in concrete. In obtaining one of the outputs using TCD which is critical distance, fatigue limit of concrete that is obtained through laboratory testing and stress field generated using computational analysis engineering software (CAE) are required. In this article, the concern will be on producing the valid and reliable stress field data since inaccurate input into the CAE will result unreliable output that is exposed to errors. In order to guarantee the result is accurate, validation works were conducted in preprocess and post-process phase while analysing finite model using ABAQUS. As the outputs comply accordingly based on the validation works, the critical distance is confidence to be consumed for the subsequent research related to TCD

PRIORITIZATION OF THREAT FACTORS FOR PIPELINE OPERATOR’S REPUTATION SUSTAINABILITY FROM CUSTOMER’S PERSPECTIVES

A company reputation solely depends on how their stakeholders perceive them and their attributes, e.g., onshore oil and gas pipeline damage; sustaining the company reputation level amidst this deadly event is a great challenge to the owner. This article aimed to prioritise the contributing indicators of reputation loss as influenced by the customer perspective. These indicators were identified according to the 10 major onshore oil and gas pipeline explosion case studies; about 72 respondents had participated in the survey for data collection. Fuzzy analytic hierarchy process (FAHP) method was used to prioritise the factors and produced results as follows: factor A3 “Downgraded owner’s ranking by ranking agencies”, factor B2 “Bad word-of-mouth among customer”, factor C3 “Accident facts hidden for personal interest” and factor D3 “Accident severity” were chosen to be the highest priority based on the customers’ perception. This factor rioritisation process assists the owner to attend to these matter so that the impact of reputation loss, which influenced by the customer, may be avoided. Eventually the consequence assessment for pipeline damage can be successfully applied to evaluate the level of loss to be borne by the asset owner and eventually sustain the reputation of the company

Mechanical properties of carbon nanotubes-modified epoxy grout for pipeline repair system

Epoxy grout properties are theoretically important in predicting the behaviour of the composite pipeline repair system. Usually, it is used as an infill material to fill the gap or irregularity on the surface caused by pipe corrosion and ensures a smooth bed before fibre wrapper can be applied to recover the pipeline strength. In this research, the existing commercially available epoxy resin grout has been strengthened by using Carbon Nanotubes (CNTs) at the amount 0.1% of weight fractional to evaluate their apropos behaviour to the neat epoxy grout. The various mechanical tests were performed on this modified grout to identify its compression, tensile, flexural and lap shear strength. In addition, the dispersion process of CNTs was carried out by using ultrasonication and three-roll mill technique to ensure an optimum enhancement in the properties of the polymer matrix. By comparing the strength, 0.1% of CNTs filler has significantly improved the strength of grout in flexural, tensile and shear bonding but not in compression. In addition, the results also indicate that CNTs filler has increased the modulus of elasticity of the infill material. Therefore, it demonstrates the intrinsic potential of the CNTs in modifying the properties of the epoxy grout

Mechanical Properties of Graphene-Modified Epoxy Grout for Pipeline Composite Repair

In general, when the pipeline experiences metal loss on the external surface, epoxy grout has always be used to fill the gap before fibre reinforced composite can be applied to recover the pipeline strength. In this research, the existing commercially available epoxy grout has been strengthened using graphene nanoplatelets (GNPs) at the amount of 0.1wt% to enhance its mechanical properties. Various mechanical tests were conducted on this modified epoxy grout to identify the compression, tensile, flexural and shear properties and were compared to the neat epoxy grout to observe its potential improvement. GNPs were dispersed using a sonication process followed by three-roll milling technique to ensure a uniform and homogeneous dispersion within the epoxy matrix can be well achieved. The experimental results clearly show an improvement in the strength and Young’s modulus especially for tensile, flexural and lap shear test by incorporating GNPs as additives. The presence of GNPs has a significant reinforcement effect and has succeeded in increasing the ductility of the grout, thus reducing its brittle behaviour. This gives an indication that the performance of modified epoxy grout is expected to be reliable and capable to minimize sudden rupture of the pipeline due to bursting

Prioritization of identified environmental loss factor subject to offshore structure failures based on public perception

Oil spill disturbs an entire ecosystem for a quite long period of time, environment impacted by this event but less attention was drawn due to lack on documentations. This paper presents a study of the past accident related to the offshore oil and gas accident that contribute to environmental loss. It intend to assess the environmental loss quantitatively. Referring to nine cases of the worst offshore accident related to structure failure in the previous years (1969-2011), the cause of failure that contribute to oil spill and environmental loss in the previous cases was identified and categorized based on the environmental loss characteristics. Finally, data collected from the past accident is used to design the questionnaire survey in order to obtain the public perception and analysis is done by using average index of non-parametric test and analytic hierarchy process for prioritization the factor of environmental loss factor. The result shows that water pollution, air pollution, marine animal and fisherman denoted as A1, A2, B1 and C1, respectively, are very important are the most affected factor. Identifying the loss of environmental loss factor is a crucial contribution to the enhancement of the calculation of COF as well as risk assessment

Influence of environmental parameters on microbiologically influenced corrosion subject to different bacteria strains

Microbiologically influenced corrosion (MIC) is capable on weakening the metal’s strength, eventually leads to pipeline leakage, environmental hazard and financial loss. Sulfate reducing bacteria (SRB) is the principal causative organism responsible for external corrosion on steel structures. To date, considerable works have been conducted in Malaysia on the mechanisms of SRB upon MIC on the marine environment instead of underground. Moreover, commercial bacteria strain represents local strain in terms of performance and behavior upon corrosion of steel structure is yet to be proven. Thus, this paper aims to investigate the influence of environmental parameters towards MIC in corroding pipeline. Two types of SRB strain were used designated as SRB ATCC 7757 (commercial) and SRB Sg. Ular (local strain) isolated from Malaysian soil. The behavior of both strains was critically compared by calculating the rate of corrosion upon carbon steel coupons in stipulated environmental parameters. Four influential parameters i.e. pH, temperature, salinity concentration and iron concentration were considered. Collected data presented and analyzed using graphical and statistical analysis, respectively. The results showed the difference of corrosivity between two SRB strains in terms of corrosion behavior upon the X-70 steel coupon. SRB Sg. Ular able to cause severe effects upon steel structure as compared to SRB ATCC 7757 due to its aggressiveness shown by the recorded metal loss data. Thus, future works related to MIC for local environment in particular, should not compromise with the type of SRB strains considered due to differences of performance of the microorganisms onto tested environment and materials

Effect of Multi-Walled Carbon Nanotubes on Infill Material for Pipeline Composite Repair

The properties of the infill material are an important parameter in predicting the performance and behaviour of Fibre Reinforced Polymer (FRP) composite for effective design. This paper identifies the potential of Multi-walled Carbon Nanotubes (MWCNTs) as nanofiller in enhancing the performance of infill material. Two compositions of MWNTs at 0.1% and 0.5% of weight fractional were evaluated toward neat epoxy on tensile and lap shear test. By comparing MWCNTs-based modified epoxy grouts and neat epoxy grout, a significant increase in tensile strength was observed, especially with 0.5% of MWCNTs by almost 53.3%. While the inclusion of MWCNTs showed a comparable increment in shear strength in both 0.1% and 0.5% weight fractional by 13%. The image of morphologies showed that MWCNTs were well incorporated into the matrix, making the cross-section of the fracture rougher by sharing stress. This shows the potential of the MWCNTs in changing the properties of the modified epoxy grout, provided that the MWCNTs are appropriately dispersed throughout the resin matrix

Stress distribution analysis of composite repair with carbon nanotubes reinforced putty for damaged steel pipeline

Composite pipeline repair systems involving infill material and composite wrapper are a common method of enhancing the integrity of damaged oil and gas pipelines. Composite wrappers can be theoretically optimised by minimising the layers of wrapper whilst reinforcing the infill material; i.e., putty. Integrating nanomaterial into putty to enhance its strength is a novel approach to provide secondary layer protection of damaged pipelines. A finite element model simulating a composite repaired pipe was developed to investigate the influence of reinforced Carbon Nanotubes putty on the system's overall repair performance and behaviour. The result was verified with a previous experimental hydrostatic burst pressure test and industrial standard resulting in less than a 15% error margin. The result shows the damaged artificial pipe segment filled with two different putties, namely Grout A and Grout B, ruptured at 32.22 MPa and 32.93 MPa, respectively. The reinforced putty improved the load-bearing capacity of the repaired pipe by a marginal increment of 2.2%. It demonstrated a better load-transfer and load-sharing mechanism than the common composite repair system. The recorded burst failure of the repaired pipe was less abrupt, thus minimising the sudden rupture of the pipeline by acting as a secondary layer of protection in the event of a composite wrapper failure