A Historical Review of Pre-Commissioning Hydrotest Failures

2006 ◽  
Author(s):  
Andrew Cosham ◽  
Robert J. Eiber ◽  
Robert Owen ◽  
Jan Spiekhout
Keyword(s):  
Historical Data ◽  
Safety Margin ◽  
Historical Review ◽  
Pipeline System ◽  
Engineering Structures ◽  
Line Pipe ◽  
The North ◽  
The Usa ◽  
Pipeline Design ◽  
Design Pressure

The concept of proof testing engineering structures has its origins in antiquity. The pre-commissioning hydrostatic test (also known as the pre-service pressure test) has been an important part of the process of commissioning a newly constructed pipeline for over 50 years, since its beginnings in the 1950s in the USA. The purpose of the hydrotest is several-fold: to prove the leak tightness of the pipeline system at a pressure above the design pressure, as a strength (proof) test to identify (fail) defects and sub-standard pipe, and to prove a safety margin above the pipeline design pressure. Historical data, from PARLOC (Pipeline and Riser Loss of Containment), the OPS (Office of Pipeline Safety) 30 day Incident Reports, and the published literature on the number and causes of pre-commissioning hydrotest failures has been reviewed. The historical data covers onshore gas transmission pipelines in the USA and the UK, and gas and liquid pipelines in the North Sea. The data covers the period from 1952 to 2005, although there are significant gaps in the data (e.g. the OPS data for the USA does not report test failures after 1984). In this paper, the historical data is summarised over this period, by year, in terms of the number of failures per km, and trends in the frequency and type of failures are identified. Comparison of USA and UK experience, or onshore and offshore experience, is contentious because of the influences of different design codes, and local custom and practice. The USA and UK pipeline design code requirements for the hydrotest are summarised in the paper, and it is shown that some of the trends in the failure data may be explained by the differences between the codes. Failures during the hydrotest are rare, but occasionally they do occur. The general consensus is that failures during the precommissioning hydrostatic test are now less common, and that failures due to defective line pipe (rather than due to leaking fittings) are rare. The historical data supports this consensus, but it also highlights that it is largely based on anecdotal evidence rather than data and analysis, because information on test failures is not now routinely gathered and published. The results of the historical review demonstrate that understanding the causes and reasons for hydrotest failures is important for learning from past mistakes, and also for identifying those cases where it may be possible to dispense with a pre-commissioning hydrotest. Reliable historical data on hydrotest failures is necessary to quantify trends over time, and to understand the causes of failures. The pipeline industry as a whole is not coherently recording this data. It should be.

Limit State Design Based on Experimental Methods for High Pressure Subsea Pipeline Design

2010 ◽  
Author(s):  
Chris Alexander
Keyword(s):  
High Pressure ◽  
Limit State ◽  
Experimental Methods ◽  
Economic Benefits ◽  
Thick Wall ◽  
Pipeline System ◽  
Potential Cost ◽  
Limit State Design ◽  
Pipeline Design ◽  
Design Pressure

The design of offshore subsea pipelines is facing new challenges as the pipeline industry is moving into environments requiring high pressure design. Conventional pipeline design codes such as ASME B31.4 and B31.8 establish pressure limits based on percentage of the pipe material’s minimum specified yield strength. While this has traditionally worked for relatively thin-walled pipe at moderate pressures, there are concerns that full utilization of the material’s capacity is not being realized when designing for high pressure conditions. Additionally, there are concerns regarding the ability to achieve high quality manufacturing and consistently fabricate welds in thick-wall pipes. This paper presents details on a testing program that incorporated full-scale burst testing to qualify the design pressure for an 18-inch × 0.75-inch, Grade X65 subsea gas pipeline using the methodology of API RP 1111. A lower bound burst pressure was established based on the recorded burst pressures to which a design margin of 0.72 was applied to determine a design pressure. Had the pipeline been conventionally-designed using ASME B31.8, the design pressure would have been 3,900 psi. However, using the experimentally-based design option in API RP 1111 the resulting design pressure was 4,448 psi. This results in a net increase in the design pressure of 14 percent. When one considers either the potential cost savings in material requirements at construction or the additional throughput associated with higher design pressures for a given pipeline system, it is not difficult to demonstrate the economic benefits derived in performing a more rigorous material qualification and limit state design process based on experimental methods as presented in API RP 1111.

Turbomachinery Selection Processes for Pipeline Service Revised and Updated Through Incorporation of Lessons Learned

2000 ◽  
Author(s):  
A. Cleveland ◽  
E. Humphries
Keyword(s):  
Natural Gas ◽  
Lessons Learned ◽  
North Slope ◽  
Pipeline System ◽  
The North ◽  
Selection Processes ◽  
North Slope Of Alaska ◽  
The Usa ◽  
Major Pipeline

In 1975 two companies were competing for the opportunity to design and build a major pipeline system to carry natural gas from the North Slope of Alaska and the Beaufort Delta to markets in Canada and the USA.

Preliminary results of the study on the reasons of the Hai Hau erosion phenomenon

2007 ◽  
Vol 29 (3) ◽  
pp. 415-426
Author(s):  
Pham Van Ninh ◽  
Phan Ngoc Vinh ◽  
Nguyen Manh Hung ◽  
Dinh Van Manh
Keyword(s):  
Mathematical Modeling ◽  
Historical Data ◽  
Middle Part ◽  
Red River ◽  
Erosion Process ◽  
Red River Delta ◽  
The North ◽  
Severe Erosion ◽  
North And South ◽  
Very High

Overall the evolution process of the Red River Delta based on the maps and historical data resulted in a fact that before the 20th century all the Nam Dinh coastline was attributed to accumulation. Then started the erosion process at Xuan Thuydistrict and from the period of 1935 - 1965 the most severe erosion was contributed in the stretch from Ha Lan to Hai Trieu, 1965 - 1990 in Hai Chinh - Hai Hoa, 1990 - 2005 in the middle part of Hai Chinh - Hai Thinh (Hai Hau district). The adjoining stretches were suffered from not severe erosion. At the same time, the Ba Lat mouth is advanced to the sea and to the North and South direction by the time with a very high rate.The first task of the mathematical modeling of coastal line evolution of Hai Hau is to evaluate this important historical marked periods e. g. to model the coastal line at the periods before 1900, 1935 - 1965; 1965 - 1990; 1990 - 2005. The tasks is very complicated and time and working labors consuming.In the paper, the primarily results of the above mentioned simulations (as waves, currents, sediments transports and bottom - coastal lines evolution) has been shown. Based on the obtained results, there is a strong correlation between the protrusion magnitude and the southward moving of the erosion areas.

scholarly journals Tracking a Coastal Wave Buoy, Lost from the Southern Coast of Jeju Island, Using Lagrangian Particle Modeling

2021 ◽  
Vol 9 (8) ◽  
pp. 795
Author(s):  
Seongbong Seo ◽  
Young-Gyu Park
Keyword(s):  
Japan Sea ◽  
Jeju Island ◽  
East China ◽  
Northwest Pacific ◽  
Southern Coast ◽  
Lagrangian Particle ◽  
The North ◽  
Particle Modeling ◽  
The Usa ◽  
Tracking Model

A coastal wave buoy was lost near Jeju Island, Korea, in late July 2014 and found at Cape Mendocino, USA, in April 2020. The buoy’s journey was simulated with a Lagrangian particle tracking model using surface ocean currents and wind data at 10 m above sea level. Experiments were conducted with windage values of 0, 2, and 4%. Particles were released along the southern coast of Jeju Island from 31 July to 8 August 2014. When the windage was 0 or 2%, most particles reached the northwest Pacific via the East/Japan Sea or East China Sea, respectively. With 4% windage, very few particles entered the North Pacific. Under 0% windage, particles accumulated in the Great Pacific Garbage Patch (GPGP) and never reached the USA. Under 2%, particles were able to escape the GPGP and started to reach the USA coast 2 years and 7 months after the release. The trajectory of the buoy was deduced from the trajectories of particles with a similar travel time. The buoy likely moved to East China and then to the subtropical convergence zone, where it must have circulated for approximately 2 years before being pushed toward Cape Mendocino by the intensified winter westerlies.

scholarly journals Do Different Models Induce Changes in Mortality Indicators? That Is a Key Question for Extending the Lee-Carter Model

2021 ◽  
Vol 18 (4) ◽  
pp. 2204
Author(s):  
Ana Debón ◽  
Steven Haberman ◽  
Francisco Montes ◽  
Edoardo Otranto
Keyword(s):  
Historical Data ◽  
Mortality Rates ◽  
Parametric Model ◽  
Mortality Data ◽  
Block Bootstrap ◽  
Functional Anova ◽  
Model Block ◽  
The Usa ◽  
Data Constraints ◽  
Carter Model

The parametric model introduced by Lee and Carter in 1992 for modeling mortality rates in the USA was a seminal development in forecasting life expectancies and has been widely used since then. Different extensions of this model, using different hypotheses about the data, constraints on the parameters, and appropriate methods have led to improvements in the model’s fit to historical data and the model’s forecasting of the future. This paper’s main objective is to evaluate if differences between models are reflected in different mortality indicators’ forecasts. To this end, nine sets of indicator predictions were generated by crossing three models and three block-bootstrap samples with each of size fifty. Later the predicted mortality indicators were compared using functional ANOVA. Models and block bootstrap procedures are applied to Spanish mortality data. Results show model, block-bootstrap, and interaction effects for all mortality indicators. Although it was not our main objective, it is essential to point out that the sample effect should not be present since they must be realizations of the same population, and therefore the procedure should lead to samples that do not influence the results. Regarding significant model effect, it follows that, although the addition of terms improves the adjustment of probabilities and translates into an effect on mortality indicators, the model’s predictions must be checked in terms of their probabilities and the mortality indicators of interest.

Art book publishing in Canada

1992 ◽  
Vol 17 (3) ◽  
pp. 34-37
Author(s):  
Melva J. Dwyer
Keyword(s):  
Book Publishing ◽  
Book Production ◽  
Government Grants ◽  
The North ◽  
Quebec French ◽  
The Usa ◽  
Publishing Houses ◽  
Added Benefit ◽  
The Cost ◽  
Inuit Peoples

Canadian publishing was inhibited from the beginning by Canada’s colonial origins and dependence on Great Britain and the USA. Few art books were published until quite recently; the relatively small, scattered population, the flooding of the market with British, American and (in Quebec) French books, and limited (at best) or non-existent sales outside Canada continue to be constraining factors. The necessity to include both English and French texts adds to the cost of book production in Canada. The publication of art books, and of exhibition catalogues, depends on the availability of government grants. Publications on the art of the North American Indian and Inuit peoples are an exception, attracting widespread interest and leading in some instances to co-publishing initiatives. In addition to the larger publishing houses, a number of small presses produce occasional art books, thanks to grants and in a few cases with the added benefit of sales abroad achieved through international networking. A government programme of support for Canadian publishing, launched in 1986, is continuing.

Case Studies Highlighting Rapid Repair Methods of Pressurised Pipelines Damaged by Anchors

2018 ◽  
Author(s):  
Dale Millward
Keyword(s):  
Case Studies ◽  
Health And Safety ◽  
Cost Effective ◽  
Pipeline System ◽  
Subsea Pipeline ◽  
Damage Scenarios ◽  
Fail Safe ◽  
Subsea Pipelines ◽  
Marine Vessels ◽  
Pipeline Design

Effective pipeline design and regular maintenance can assist in prolonging the lifespan of subsea pipelines, however the presence of marine vessels can significantly increase the risk of pipeline damage from anchor hazards. As noted in the Health and Safety Executive – Guideline for Pipeline Operators on Pipeline Anchor Hazards 2009. “Anchor hazards can pose a significant threat to pipeline integrity. The consequences of damage to a pipeline could include loss of life, injury, fire, explosion, loss of buoyancy around a vessel and major pollution”. This paper will describe state of the art pipeline isolation tooling that enables safe modification of pressurised subsea pipelines. Double Block and Bleed (DBB) isolation tools have been utilised to greatly reduce downtime, increase safety and maximise unplanned maintenance, providing cost-effective solutions to the end user. High integrity isolation methods, in compliance with international subsea system intervention and isolation guidelines (IMCA D 044 / IMCA D 006), that enable piggable and unpiggable pipeline systems to be isolated before any breaking of containment, will also be explained. This paper will discuss subsea pipeline damage scenarios and repair options available to ensure a safe isolation of the pipeline and contents in the event of an incident DNV GL type approved isolation technology enables the installation of a fail-safe, DBB isolation in the event of a midline defect. The paper will conclude with case studies highlighting challenging subsea pipeline repair scenarios successfully executed, without depressurising the entire pipeline system, and in some cases without shutting down or interrupting production.

scholarly journals The Northern Policy of George 1. to 1718

1906 ◽  
Vol 20 ◽  
pp. 79-107
Author(s):  
J. F. Chance
Keyword(s):  
Great Britain ◽  
Historical Review ◽  
The North ◽  
Peter The Great ◽  
The Subject ◽  
The Baltic ◽  
Northern Policy

The policy pursued by George I. in the north of Europe in the first years of his reign has not received much attention from historians, at least in England. The few paragraphs which authors of such merit as Lord Mahon or J. R. Green allot to the subject show that they did not think it worth while, or were not able, to inform themselves of the facts. They record, rightly enough, that George's own principal purpose was to add the Swedish provinces of Bremen and Verden to his electoral dominions, and they attribute to Charles XII. the design of invading Great Britain in revenge, with the object of placing James III. upon the throne. Though he does not appear to have ever seriously contemplated such a thing, the belief that he held it in view was, after the Jacobite rebellion, genuine and general. But nothing is said of the pressing importance to Great Britain of the Baltic commerce, with which Charles interfered and Peter the Great seemed likely to interfere. This it was solely that gave George I. the services of a British squadron in the Baltic in 1715, and this the principal cause of the estrangement between Great Britain and Russia, which lasted for over twenty years. The object of the present paper is to present a narrative of events up to the death of Charles XII., from which conclusions may be drawn. Details may be avoided, as these have appeared in papers by the author published in the ‘English Historical Review.’

scholarly journals Military and Political Integration of the Scandinavian Countries in the European Security Architecture after the Second World War

2017 ◽  
pp. 39-52
Author(s):  
Valerii Pavlenko
Keyword(s):  
Foreign Policy ◽  
Soviet Union ◽  
Political Integration ◽  
Security Architecture ◽  
European Security ◽  
Close Link ◽  
Eu Member States ◽  
The North ◽  
The Usa ◽  
The Military

The Article examines the military and political integration of Scandinavia in the European security architecture after 1945 and analyzes the historical experience of the countries of the North Europe in the late 1940s-1960s in the security space issues. Particular attention is paid to the close link between the military and political rapprochement with the processes of the economic, technological and political integration in the Western European region. It is emphasized that the economic basis of common interests encourages the EU member states all the time to seek peaceful means to resolve possible disputes. Considerable attention is paid to the analysis of alternative approaches to the European security that the North European countries have used in their foreign policy. The role and place of these countries in the sphere of the European security during the late 1940s-1960s was determined. The influence of the USA and the USSR on the formation of the foreign policy of the Scandinavian countries, especially the pressure of the Soviet Union on Finland in its attempts to get a neutral state status, has been shown. The reasons for the failure to implement the military and political cooperation projects in the form of the Scandinavian Defense Alliance have been revealed.

scholarly journals Ethnopolitical Tensions and Assessment of the Possibility of Ethnic-National Conflicts

2019 ◽  
Vol 7 (3) ◽  
pp. 22-39
Author(s):  
Vitaly N. Naydenko
Keyword(s):  
Russian Federation ◽  
Social Situation ◽  
Russian Society ◽  
North Caucasus ◽  
Tension Development ◽  
Caucasus Region ◽  
The North ◽  
The Usa ◽  
The Russian Federation ◽  
The Republic

The article examines the problems of open and latent ethnonational tension in Russian society, which in the conditions of aggravation of the social situation, may lead to the use of spontaneous methods of solving ethnonational conflicts, including those of a violent nature. A survey of 20 experts, who are qualified specialists in the sphere of ethno-extremism counteraction and ethno-national conflict localization, conducted by the author of the article, has shown that the majority of them have assessed both the current and forecasted situation in the sphere of ethnonational relations as “tense” for the next five to seven years. In their opinion, “ethnonational tension” is conditioned by a number of long-term factors that will influence the content and dynamics of ethnonational conflict in the Russian Federation: the desire of the USA for global dominance and the confrontational policy of NATO member states towards Russia; the antiRussian policy of the Ukrainian leadership, which is attempting to accuse Russia of “unleashing and waging a hybrid war against Ukraine” and actively pushing Western countries to strengthen confrontation with the Russian Federation; attempts by some states to bring territorial claims against Russia; intensification of the fight against embezzlement of budgetary funds, systemic corruption and ethno-extremist manifestations in the North Caucasus region; the ethnopolitical situation in the Republic of Crimea, characterized by manifestations of Ukrainian nationalism and militant Islamism. According to expert estimates, the highest degree of ethnonational tension is currently maintained in the Republic of Dagestan, the Republic of Ingushetia, the Kabardino-Balkarian Republic, the Karachayevo-Circassian Republic, the Republic of Crimea, the Republic of Bashkortostan and the Republic of Tatarstan. The results of research in the article testify to the necessity of constant study of the problem of ethnonational conflicts, research into the factors influencing the maintenance and dynamics of conflict potential, definition of Russian regions with an increased level of tension, development of recommendations to authorities on prevention and localization of ethnonational conflicts.

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