Relative Importance of Defects in Girth Welds of Linepipes

Author(s):  
Oddvin O¨rjasaeter ◽  
Per J. Haagensen ◽  
Hans Olav Knagenhjelm

The Ormen Lange deepwater gas field is located at water depth down to 1100 meters. The irregular seabed gives severe challenges to pipeline design and verification program was launched to demonstrate adequate fatigue capacity. The research included: modern welding techniques (5G and 2G welding positions), mapping of actual welding defects, misalignment (high/low) and lack of penetration. The thick walled pipe (35mm) showed low or even compressive residual stresses at the inside. This will to some extent be “protective” to the root of the weld. The exceptions to this pattern were the repair welds and the two-sided welds. The small scale test results fell close to the full scale pipe tests when taking into account the geometrical weld distortions, loading mode, and the distribution of weld defects. The importance of the parameters influencing the fatigue capacity could be ranged as follows, most detrimental first: large crack-like defects (LOP, undercut > 1mm), hi/lo, and V-shape (radial shrinkage at the girth weld).

Author(s):  
Peter Schaumann ◽  
Alexander Raba ◽  
Anne Bechtel

Grouted connections represent a common joining technique between substructure and foundation piles of offshore oil & gas platforms as well as of offshore wind turbines. Due to cyclic loads arising from wind and wave actions the fatigue performance of the connection has to be considered. In lattice substructures like jackets the grouted connections are located at seabed level being fully submerged during their entire lifetime. Today’s fatigue design regulations are based on investigations neglecting any influence of the surrounding water since they were conducted in dry ambient conditions. So far, only Germanischer Lloyd gives additional recommendations for submerged grouted connections. At the Institute for Steel Construction, Leibniz Universität Hannover, Germany investigations of the joint research project ‘GROWup’ focus on the fatigue performance of axially loaded grouted connections. The project is funded by the Federal Ministry for Economic Affairs and Energy (BMWi, funding sign: 0325290) and is the third project in a row dealing with grouted connections. As part of this research project, cyclic loading tests on small-scale and large-scale grouted connections with shear keys are conducted. Small-scale fatigue tests showed a reduced number of endurable load cycles for connections when tested in wet ambient conditions. However, the transferability of these findings to a larger scale was still doubtful due to unknown scale effects. Therefore, the impact of water on the fatigue performance was tested recently at large-scale grouted connections. Previous to the submerged large-scale grouted connection fatigue tests, similar test specimens were exposed to alternating loads at dry ambient conditions. Comparison of both large-scale test results under wet and dry conditions enable to estimate the influence of water on the fatigue performance of grouted connections. Reflection of the small-scale test results gives hints on the scale effect. Test preparation, test results and design recommendations are presented in the paper.


Author(s):  
Satoru Takano ◽  
Masao Ono ◽  
Sotaro Masanobu

For a fundamental understanding of pipe wear under hydraulic transportation of deep-sea mining, a small scale test is conducted because there are many restrictions in conducting a full scale test. The small scale test apparatus are set up using the pipes of about 80mm in diameter and the rocks of which maximum particle diameters are about 20mm are used. In the test, the pipe materials and the pipe inclination are changed to evaluate the differential of the amount of pipe material loss. Furthermore, the amount of the pipe material loss in full scale is estimated based on the small scale test results.


Author(s):  
Olav Fyrileiv ◽  
Dag O̸. Askheim ◽  
Richard Verley ◽  
Hanne Rolsdorph

This paper deals with clump weights, a new type of component in bottom trawl gear that needs to be considered in design and reassessment of pipelines. In recent years it has become popular to use two trawl bags, a so-called twin trawl, to increase the swept area and, thus, the efficiency of the trawler. In addition to the trawl boards at each side of the trawl bags, a heavy weight, a clump weight, is used between the bags to keep them close to the seabed. Clump weights can have a mass up to 9 tonnes, and the largest ones are shaped as spheres or cylinders inside a steel frame. Tests performed have revealed that the loads on pipelines from clump weights may exceed the corresponding loads from trawl boards. Thus, interaction with clump weights may govern the design and qualification testing of coating, and the design related to global pipeline response. This paper discusses loads from clump weights. Updated design approaches including pull-over load estimates are presented. The background in terms of small scale test results is also shown for some cases. The conclusion is that clump weights may govern the trawl design of pipelines, especially for trawl gear impact and pull-over.


2021 ◽  
Vol 4 (1) ◽  
pp. 67-72
Author(s):  
Khoirun Nisa ◽  
Ismi Nurul ◽  
Mistianah Mistianah

This study aims to produced eMMI based on multiple intelligence (eMMI) with 3D pageflip pro for biology student’s in IKIP Budi Utomo Malang, in the circulatory system material that is suitable for used in the learning process. This research was developed with a 4-D model consisting of definitions, planning, development and dissemination. Data collection using a questionnaire. This eMMI have been validated by material experts and media experts.The evaluation results from material validation, is known that above 90%, while the results of media validation are above 96%. Small scale test results indicate the validity results above 90%. From the results of the validation of media experts and material experts, it is stated that the e-eMMIe is suitable for use and based on the questionnaire, it can be said that students and teachers are expected to really take advantage of teaching materials in order to create interesting and fun learning in physics learning.


Author(s):  
Tomiaki Furuya ◽  
Terunobu Hayata ◽  
Susumu Yamanaka ◽  
Junji Koezuka ◽  
Toshiyuki Yoshine ◽  
...  

Catalytic combustion for gas turbine applications has been investigated. Its significant advantages in reducing combustor emissions, particularly nitrogen oxides (NOx), have been shown. One of the main problems in regard to developing a catalytic combustor is the durability of catalysts, because the catalysts deteriorate during high temperature operation, which is normal for current gas turbines and near future gas turbines. The hybrid catalytic combustion concept has advantages concerned with catalyst durability. This paper shows its concept and small scale test results. This hybrid catalytic combustion concept comprises the following steps; premix fuel and air for a catalyst-packed zone; operate catalysts at rather low temperatures, to prolong catalyst life; add fresh fuel into the stream at the catalyst-packed zone outlet, where gas phase combustion occurs completely without a catalyst; add dilution air into the stream at the gas phase combustion zone outlet with a by-pass valve. Experimental data and analyses indicated that this hybrid catalytic combustion has a potential of being applicable to current gas turbines (turbine inlet temperature is about 1100°C) and near future gas turbines (turbine inlet temperature is about 1300°C).


Author(s):  
Tore Roberg Andersen ◽  
Jan Ivar Skar

A test program has been performed to obtain the permeation coefficients for methane, carbon dioxide and water in PVDF. Small-scale tests showed that water is transported through the PVDF inner sheath of the flexible pipes, and into the annulus. A large-scale test was carried out to verify the small-scale test results. It was performed in a 2″ flexible pipe with length 3 m. The bore temperature and pressure were 100°C and 50 bar, respectively. The pipe was submerged in cold water in order to get a correct temperature gradient in the pipe. The test showed that the annulus of flexible pipe with PVDF inner sheath would become water wet due to permeation, depending upon the bore and annulus conditions.


2020 ◽  
Vol 4 (2) ◽  
pp. 243-252
Author(s):  
Putri Vina Sefaverdiana ◽  
Melisa Wahyu Fandyansari

Indonesian Cooperative textbooks are development research aimed at developing quality textbooks and can effectively improve understanding of existing cooperatives in Indonesia. Textbooks as a support in Cooperative lectures, in order to improve student learning in class so that students have understanding and skills in cooperating. The purpose of this textbook is to make it easier for students to learn and understand as a provision for students to develop cooperatives in their respective areas of residence. The method in this research is a research and development research using a model from Dick and Carrey. The test results obtained from the first material expert were 84.5%, the second material expert obtained 76.4%. 3%. After the expert test was carried out a small-scale test where the result was 82.6% and the large-scale test obtained a result of 86.3%. From the results of the percentage, it states that the textbook is in the good category and is feasible to apply


Author(s):  
Tadahiro Washiya ◽  
Toshiaki Kikuchi ◽  
Atsuhiro Shibata ◽  
Takahiro Chikazawa ◽  
Shunji Homma

Crystallization is one of the remarkable technologies for future fuel reprocessing process that has safety and economical advantages. Japan Atomic Energy Agency (JAEA) (former Japan Nuclear Cycle Development Institute), Mitsubishi Material Corporation and Saitama University have been developing the crystallization process. In previous study, we carried out experimental studies with uranium, MOX and spent fuel conditions, and flowsheet analysis was considered. [1, 2, 3] In association with these studies, an innovative continuous crystallizer and its system was developed to ensure high process performance. From the design study, an annular type continuous crystallizer was selected as the most promising design, and performance was confirmed by small-scale test and engineering scale demonstration at uranium crystallization conditions. In this paper, the design study and the demonstration test results are described.


2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Ina Riana ◽  
Rida Fironika Kusumadewi ◽  
Nuhyal Ulia

Abstrak. This research is to develop and find out the feasibility of "Creative Factor" teaching material products on multiples and number factors. "Creative Factor" teaching material products multiples and number factors are developed based on the teacher's need for other reference sources in learning. This research uses the Research and Development (RnD) method. The development of "Creative Factor" teaching material products uses a development research procedure according to Sugiyono that contains 10 thrones. Based on this, the research results obtained include: (1) the validation results from 4 experts obtained an average score of 84 and a percentage of 90% with the criteria "Very Eligible". (2) the results of the small-scale test get teacher responses obtained by the percentage of 88% with the criteria "Very Practical". While the results of student responses obtained 97.2% percentage "Very Practical". (3) large-scale test results obtained by teacher responses obtained by the percentage of 90% with the criteria "Very Practical". While the results of student responses obtained 96% percentage "Very Practical". Based on these results, the development of "Creative Factor" teaching material products can be declared worthy to be used as a companion in the learning process.


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