EN ISO 12215:2018 full mandatory

Discussion in 'Class Societies' started by Alan Cattelliot, Jul 6, 2021.

  1. Alan Cattelliot
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    Alan Cattelliot Senior Member

    Boat builders should now, since July 1st 2021, be aware that the presumption of structural conformity of their products still on the market, has now expired.
    upload_2021-7-6_22-52-52.png
    Every boat put on the EC market should now be compliant with the revised 12215 standard.
    This revision follows the great innovations that took place in the last 10 years in the Boat industry. It gives more options to the user to demonstrate the quality of their products. It also incites a deeper insurance quality control.
    To give you a quick highlight of how to read and use the new standard, i'm very happy to share some notes with you.
    The explanations that follows are extract from a commercial brochure from my company A.C.E. CATTELLIOT ENGINEERING. We are going to launch a mobile app called "12215 ALIVE !" in September, as an attempt to deal with the task of re-assessing the boat structure of existing boats and new ones. Light and low.



    CHOOSING YOUR METHOD


    Compared with the 2008 version, structural analysis of the revised 12215 demands to the user an additional effort to get confidence in his choice of the method. They don’t give all the same results. In cause, the “trial and error” approach for boat assessment.

    As the standard will reached his end of presumption of conformity the 1st of July, we have implemented several assessment procedures, until a consensus is attained together with official recommendations, that would allow us to go further.

    Method 1 and Method 2 are proven methods with a high level of consensus among users. Compared with the old standard, they provide updated results from new coefficients formulas, also extending options for users[1]. Their domain of validity is also very well known. Method 1 applies mostly to metallic or quasi-iso single skins, while Method 2 is more suitable for complex single/sandwich skins with oriented plies.

    Method 1 and Method 2 cover most of the practical user’s cases.

    Method 4 allows the use of your own material values, as obtained by material testing, according to the - ISO,ASTM - applicable standards. Habilitated test centers operating under ISO9001 rules are thrusted sources. Local university laboratories or independent test centers may also produce quality results, depending on their experience in the industry field.


    Method 4 will be available with usage restrictions to be acknowledged by the users.


    Method 5 is used for a pair of decades in boat industry. Most naval engineering cabinets master FE analysis. From their theorical knowledge and practical experience of the manufacturing, they are capable of producing the more realistic results[2].

    A practical implementation of the method 5 is scenarized to be put in the App in January, 2022.

    Method 3 is a more detailed method applicable to any bi-directional layered composite manufacture. It concerns most of the boat production, since the industry of Plaisance is essentially plastic-based. Using this method requires a lot of trustworthy data from the user[3]. Moreover, it has not been possible to find numerical tools to validate unbalanced material compositions with low fiber content, as it is most of the time.


    Practical solutions are still to be found[4] for Method3.


    Method 6 is the more marginal, but also the more undisputed, being optionally compatible with SOLAS examination. Services companies are present on the market, from which we have not yet an updated view.

    Method 6 will not be a priority, unless a favorable context appears.


    [1] Strictly identical in nature to the formulas in the last 12215, the new formulas are more “strain-based”, to encourage users to perform material testing, as well as to go further in their quality insurance of their production.

    [2] The unification of their own method, together with the FE implementation in the standard, pose, in the end, un-solved questions to users. An attempt to propose solutions is under currently under validation study, through our collaboration with G. Dolto in the study of composite panels with the EF method.

    [3] The material composition accessible to users of these codes are, most of the time, the thickness, the fiber orientation, the moisture level and the temperature. “Pre-Preg” technologies gain material strength in the formulas, authorizing users to balance the calculated normative efforts inside the material.

    [4] Until then, Method 5 shall be preferred.
     
  2. Alan Cattelliot
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    Alan Cattelliot Senior Member

    Of course, considering the vaste amont of work to be done on the subject, by the boat builder's and the notified bodies, i would say that every hand is needed !
    I would be very happy to exchange with you comments or notes.
     
  3. Alan Cattelliot
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    Alan Cattelliot Senior Member

  4. Alik
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    Alik Senior Member

    The variety of methods foreseen in ISO12215-5:2019 just opens space to speculations.
    The ISO12215-5:2019 is faulty standard, where the samples provided in Annexes do not match the same calculations performed by the users. Namely, this refers to laminate stack analysis samples. The same problem we experienced with ISO12215-10 standard - samples provided in the standard do not match.

    The FEA approach they propose is not worth touching for local strength, as with given safety factors results will be worse than laminate stack analysis. It is only reasonable for craft with small number of stiffeners and very curved panels. Also, tested and validated.

    We are already using this new standard, as well as ISO12215-7 for design loads on multihulls. But I suspect it would be the challenge to prove that calculations are correct - there is no basis for validation.
     
  5. Alan Cattelliot
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    Alan Cattelliot Senior Member

    Hi Alik,

    There is no speculations at all in the basic formulas that have been put into the standard, which are very simple indeed, perhaps too much simple. I just remember that the last version off this standard has been critized for basically the same reasons. The truth is that it was, and it is still, a very difficult document to read and to get your hands on. You're absolutely right, Alik. This new standard is not perfect and is very troublesome.

    i agree with you :
    12215-7-12215-10 / Indeed, around the table when writting this new standard, there have been a lot a trouble, caused by the divergence of the architects and designers that were present. Marc Lombard, Erik Lerouge, VPLP, GSEA,- and I personnaly - have all there own method of calculations and it has been a nightmare to turn their different point of vue into requirements for part7. Your point about being able to prove the correctness of part7 calculations is very true, and i am very surprised that it is not part of the official comments. Although the concensus among rig manufacturers has been far more easy - a little like "do whatever you want...we know what WE do"-, it also lacks of practical example.

    i don't agree with you :
    12215-5 / One should be aware that the stack analysis methods in their simple form should not be pushed to far away. It give results that are correct, in theory, only for symetrical plies sequence. Still, you probably do know that there is no concessus about the true reality of this analysis. A basic un-solved remanent question, with this method, is : "First ply failure or last ply failure" ? The same question that has been asked since the first composite have been calculated, in the 50's. Like Mulder, I would say that the "truth is out there".
    Regarding the FEA method, i also disagree with you. I've been using this very complex computations method to validate the last IMOCA's to the class rule that embedded the 12215. (In fact, I wrote the 12215 assessment guidance for IMOCA's boat that are still in use in the class rule), and i could say that the EF method has always allowed the validation of the panels or stiffeners that could'nt be validated by the method 1 and 2. So do not lose your courage, efforts will be granted, in the end !
    In another example less "extreme", the EF calculations is the only method that has given realistic results for the glass-plywood construction of several motor and sailing monohulls. If we could just have a CLT program, and i have no doubt that, with this, in the future, we won't have to perform such violent calculations to validate what is often designed correctly without any formulas, just from thin air, by our talented architects and designers.

    As a formal member of the GT18 group, i have the original validations spreadsheets that could help, but in the absence of any formal and official way of sharing it, it would be a first step if you could, requirement by requirement, precise the validation examples that you need. We will then think of a way for going further.

    Also, for all to be precise and in accordance together and with active legal disposition, when dealing with the subjet, the list downbelow shows only the harmonised parts of the standard in the past and the present (please refer to the link i've given sooner). As you can see, the part 7 and part 10 are not in, and are still a matter of actuality
    EN ISO 12215-1:2000
    EN ISO 12215-1:2018
    EN ISO 12215-2:2002
    EN ISO 12215-2:2018
    EN ISO 12215-3:2002
    EN ISO 12215-3:2018
    EN ISO 12215-4:2002
    EN ISO 12215-4:2018
    EN ISO 12215-5:2008,
    EN ISO 12215-5:2008/A1:2014
    EN ISO 12215-5:2018
    EN ISO 12215-5:2019
    EN ISO 12215-6:2008
    EN ISO 12215-6:2018
    EN ISO 12215-8:2009,
    EN ISO 12215-8:2009/AC:2010
    EN ISO 12215-8:2018
    EN ISO 12215-9:2012
    EN ISO 12215-9:2018
     
  6. TANSL
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    TANSL Senior Member

    My humble opinion, as a simple user of the standards, since I am not an expert in composites, is that their use is totally impractical. When I also see that some of its authors do not like the texts finally offered, I wonder what hands guide our destinies in this field?. We are bound by a rule that even its authors do not like, and therefore we would ask that that rule be overridden until the authors are able to come up with something really practical. In the meantime, please don't make our lives more complicated than necessary.
     
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  7. Alan Cattelliot
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    Alan Cattelliot Senior Member

    Hi TANSL,

    As you may know, by statement, the standardization process in the International Standard Organisation rely on a very strongly defended approach based on the Consensus. Admitting that we were not able to reach our objective of having a fairly practical standard, in the end of very intense discussion, is very disapointing, i totally agree. You may also know that, the work of creating this standard in the RCD scope is more than 20 years old. This very long period, as well as the numerous comments that have been made, officially or not, shows by itself the difficulty of the matter.

    I wish i had better explained, in my first post, that this new standard contains, despites imprecisions or typos, some very great embedded features that fits better with the state of art of boat's building, which are still to be shown.
     
  8. Alik
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    Alik Senior Member

    Alan Cattelliot, the speculation is not in the formulas, the speculation is in assesment of results of calculations by different methods. Most of certification bodies' surveyors are not composite experts, they are general naval architecture specialists and they should not be dragged into discussion of the theories. Thus, the standards should produce clear recommendations, and not guesses or interpretations. When I read the formula in clause 11.6.1 3), where no units are respected, I have nothing to say...

    My personal feeling, this 12215-5 standards are written by the developers for themselves, not for the industry.

    PS We are already using ISO12215-7 standard, for which I contributed, too.
     
  9. TANSL
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    TANSL Senior Member

    @Allan Cattelliot, with all due respect, because I do not know the motivations that you have had to do what you have done, I must tell you that I would never in my life give my client a product that I am not fully satisfied with. And if, in addition, I charge for it, my face would fall with shame. No, I consider myself a good professional, with professional ethics and responsible for their actions. Forgive me a direct way of saying things, but professionals, with the rules that you make, have serious problems and we are talking about what feeds us, not academic theoretical exercises.
    There are no excuses to sell a semi-finished product, impractical in real terms, that does not even have the full approval of its authors. To add insult to injury, the authors know perfectly (you know) that there are errors in the published standard and they do nothing, apparently, to correct them or, at least, to warn the buyer of the standard, of those errors.
    Please meet again with that committee of authors and reconsider what is being said here. We have a problem and only you can solve it. Thanks.
     
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  10. TANSL
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    TANSL Senior Member

    Frankly, I have been working on, against, the norm for many months and have not yet been able to see where these big improvements are. Is there something in this standard that improves the normal procedures, with much more than 20 years of validity, of the calculation of composites? Some of us would appreciate if you clarify this issue for us. Some of us are used to affirming something and proving it. Thanks again.
     
  11. Alik
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    Alik Senior Member

    This is exaclty how Russian Register of Shipping works - Krylov research center writes the rules for them, say, for high speed craft. Structural part of the Rules is full of errors, there are differences in Russian and English version in formulas, there are unknown mathematical operations and there are unspecified values. So when we ask them about these errors, the RS reply 'you can order the calculations for your designs to the Krylov center'.

    Am I right, I see the similarity here; will the standard writers offer the services on forum? ;)
     
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  12. TANSL
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    TANSL Senior Member

    Yes, I totally agree with you. I was going to say that it "seems" but I will correct myself to say that it "is" unethical to act like this. But this is not the only author who, veiled, subliminally, cunning, offers his services under the "halo" of having participated in the making of the rule.
     
    Last edited: Jul 7, 2021
  13. Alan Cattelliot
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    Alan Cattelliot Senior Member

    Guys,


    upload_2021-7-7_12-48-10.png
    You may forget something absolutely essential on the matter. It is of the greatest importance that, shifting from the old standard to the new one shall not put into questions the assessment that have been already done on existing boats. Happy or not about what will be inside, this "anteriority" requirement, to my own personnal opinion, i a very good achievement, unless I strongly invite you to show me your case.

    The fact that it has, in the standard, several methods giving different results has been motivated to give users the greater number of tools to demonstrate the conformity of their product. Think as if it is a toolbox. I guess that, with this perspective, you, Senior Members, professionnals in boat building, won't use your wrench to drive a nail.

    Again, explanations are to be done, more complete. It has been shown that, regarding the editorial requirements of ISO governing the content of a standard, in general , the standard itself could not be the place of such recommandations. What place would it be ? It is a excellent question for which i'm make proposals, besides being able right now to give you reading keys, clues, to perform with your own tools what you've been doing in the greater Peace before the Directive and after the Dinosaure.
     
  14. Alan Cattelliot
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    Alan Cattelliot Senior Member

    And also, I guess that you do not know my services, do you ? So, feel confortable, I won't be of any danger for your xls spreadsheet.
     

  15. TANSL
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    TANSL Senior Member

    You seem to be moving in an academic world that has nothing to do with the real world.
    The expert in structural calculation and composites does not need any standard. Anyone who is not an expert in such subjects, which is what happens to most designers of small boats (and also of large boats), needs a standard, a guide for the inexperienced, who with great ease and agility, will allow them to calculate the scantlings of their project, without the need to "validate" anything, with the assurance that their figures will be accepted by the official body in charge of the matter.
    Many of us know that the nail is nailed with a hammer but we do not know what the nail looks like. That is what we expect from a standard , for which we pay a non-negligible figure. Don't call us ignorant or unaware of how our tools are used.
    Why that air of superiority? What's wrong with a spreadsheet? What do you propose in the standard for layered analysis? Is your spreadsheet better than ours? In what way and why? Thank you for your, I am sure, kind explanations.
     
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