In the identification of tubular joints, the FORTRAN code together with algorism are used. In this case, the tubular types of STK; KT; T; K; X and Y are used. These kind of information are extracted from the available structural data. In this case, these tasks arise from the analyses of fatigue involving all the joints in a structure especially where this kind of analysis can not proceed without the proper use of a code (Segal, D., 1999).
This kind of analysis can also be done by analyzing a K- Joint under the North sea surrounding. In this case, an offshore platform structure being so susceptible, will be useful in helping to detect various developments experienced during this kind of operation that may be experienced as a result of fatigue crack initiation, corrosion amongst others.
At this stage, it is essential for the plat form operator to test the effects of defects that may occur on the structural integrity of the jacket(Davis, Malcolm, 2005). However, for a safety assessment of these offshore structures which have defects, the most reliable method to use is a fracture mechanic. It is worth noting that it is very costly as it involves a lot of complexities. Hence, this makes it difficult to be implemented whenever it is used.
During this analysis, it is recommended that the load life should be considered. At the same time, the other factors to consider are the stress and strain life. They are paramount in they can help a great deal in dealing with the various types of crack growths that may be experienced at this point of time. Also important for the mechanic is the carrying out of the constant aptitude test. It can also help in analyzing the linear damage that can ascertain the degree of the fracture joint being dealt with.
When doing out all these, it is necessary to adhere to a lot of rules some of which include the Miner’s Linear Damage Rule. On the other hand, a few necessary major assumptions were made to ensure that the analysis has some direction to guide it appropriately. The assumptions should be, but not limited to the following:
i) The service loading used should be the same as the loads that are used to baseline data in the whole analysis
ii) The fatigue life is dominated by the crack growths
iii) Standard classification can be used to describe the comlex weld geometry
iv) The expected results are independent of the mean stress and the nature of the steel used in the analysis
v) The stress analysis used is not the only thing to be done. Others can also be done to make the test more feasible.
vi) There is the existence of large empirical database
Meanwhile, the if all these are appropriately done, the mechanic will be well placed to automatically include the local and manufacturing types of stress besides clearly stating the actual test to the people. It can also make it very possible to evaluate the possible occurrence in changes in geometry and the material used when carrying out the analysis. This will make this kind of analysis very essential in helping to realize the major goals of the study(Howard A. P., 2009).
There should also be the use of large empirical data base made of the type of steel that is embedded with the various notch shapes. This will help in eliminating various limitations of this analysis that may include the following:
i) There are a lot of errors on the mean effects of stress. This will definitely give rise to an inaccurate result
ii) The results generated will definitely not give any slightest chance of accounting for the plasticity of the notch root used
iii) For it to generate better results, it is required the use of empirical analyses methods which may not be so easy to effectively use.
iv) It is very difficult to determine the weld class especially for the complex shapes
References.
Davis, Malcolm (2005). The Principles of Tubular Analysis. London.
Gates, A.(2006) Engineering in Practice. London: Macmillan
Howard A. P.(2009) Fatigue Analysis. New York: John Willey and Sons
Segal, D.(1999) Mechanical Engineering: Facts and Practices. New York: Sinems Publishers.
