EN ISO 12215:2018 full mandatory

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

  1. Alik
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    Alik Senior Member

    This is the main point!
    The autority should say yes or no based on the standard, and not based on opinions or discussion of theories.
    We are commercial design office, by contract we need to design in compliance with the standards. Thus, the standard should be clear.

    Now it looks like instead of set of mechanical tools to hit the nail, we are given book to read on theory of the nails.
     
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  2. TANSL
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    TANSL Senior Member

    We, poor ignorant people, confuse the wrench with the hammer, while the "scientists" confuse the norm with the nail and with it they crucify us. (Good example the one chosen by the OP):D
     
  3. Alan Cattelliot
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    Alan Cattelliot Senior Member

    Mr. Tansl,

    In the real world, rudder stocks, sometimes break because of the metal supplier that has not given the correct grade, and because the builder has not performed any test on such a vital piece on a boat. -I do not say that the builder should make systematic engagement with his customers in that sens, but here is the fact.... - In real world ,the mast of most of the multihulls engaged in a darkly famous Route du Rhum broke because designers and builders agreed to use a carbon fiber already banned in the aeronautical field.
    In the real world, all the 60' footer champion serie of boats of a very famous french workshop, designed by a very talented cabinet, had their internal metallic primary structure ripped out of the composite enveloppe because the bounding component mechanical properties have not been treated as a real subject.

    It's not that anyone has not given the best of himself, in these examples. If you're talking about real world, i would say there is a gab between the confortable desk you'r sitting now and what is being built. If you're talking about real world, i would say that there is a gab between the design world and the world of standardization. In cause, mainly, your great creativity that poses true issues in the quality managed market where we are all living.

    The 12215 standard has been developped in the scope of EC certification on the European market. This could have been easier if things would have made a stop at this point. Because in the Directive, you're not bound to use the harmonised standard as proof of conformity of your product. At the verso of the DoC given in the official link below, lies for every boat builder, the possibility to use is own referential, as long as the existence of such referential could be made into disposal for 10 years after the first sale of the model to any legal authority or in justice affairs.

    RCD 2013/53/EU Guidelines - June 2018 https://www.europeanboatingindustry.eu/newsroom/latest-news/item/66-rcd-2013-53-eu-guidelines-june-2018

    True problems come when other national associations or class rules, have decided to make mandatory in their own regulations or rules, this ISO standard, sometimes already knowing that their cause was out of the scope of the standard, or that interpretation issues will certainly come from the standard itself, in his past form or its actual.
    I find very interessant talking to you guys, because I really know that feeling of being depressed just thinking of calculating the keel plate thickness using the part 9, although it is obviously a more accepted part than the freaky number 5. As for the layered analysis explanation, i'm trying to get intel with the website manager if i can run a special code in the forum post. I will not let this question un answered, Mr. Tansl . A good drawing may be better than long discourses.
     
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  4. TANSL
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    TANSL Senior Member

    Monsieur Alan Cattelliot, I agree with you on much of what you say in your last post, not on everything.
    But I would like to know why, in the real world, a standard must be so difficult to apply. Why a rule, which is known to have errors, is not corrected or, at least, users who, I repeat, have paid for it, are not notified that those errors exist. I would like to know why a standard is so complex that its own authors offer future services (a business for them) in order to apply it correctly. You don't have to answer me, but thank you anyway for a job that, I'm sure, you thought was very honest, very good, very complete and very useful for the real world.
    Oh and if I am now sitting in a comfortable chair, it is because I have spent more years than you can imagine, kicking shipyards and working in workshops of various large, small and medium size shipyards, metal hulls and PRF. I know the world I speak of.
     
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  5. Alan Cattelliot
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    Alan Cattelliot Senior Member

    Mr. Tansl,

    I wish i could in the next post, be of a certain help on certain subject, at least giving you the best information I can is effectively due to all users, without arguing. That said, in the meanwhile, when you were at work, pushing everything forward - i must imagine with only you knife and your dick sometimes - the vast majority of the contributors to the standard have never been paid, nor time or ressource spent on the subject. What for ? Hoping to make buisness with a standard only used by a few, while most of them have only one idea in mind : To put the house in fire, together with the cook. How touching...

    I'm not old enough to digress in explaining when an where, in my experience,I developped the idea that boats could benefits from better technologies and deeper insights. From our conversation, I have gather some really interessant matter to work on, understanding better were the difficulties lies. The processus of revision of a standard can be engaged when the European Commission agrees to answer to missionned states representants, asking for reserves or modification or total annihilation of the standard. It is a legal processus that has your own will as a start.

    So for now, my advice will be to go for your national representants and push forward whatever proposition you may have, Mr Tansl.
     
  6. TANSL
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    TANSL Senior Member

    That is, you wash your hands ... like Pilate.
    I can carry out many sessions, in my country and abroad, of course, but what better way than to ask the authors? I will make the query to AENOR, but where is the responsibility and professionalism of the authors? Are they only responsible for what they charge money for?
     
  7. Alik
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    Alik Senior Member

    I think by EU consumer protection laws, You can claim low quality of standards You buy from ISo_Org?
     
  8. TANSL
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    TANSL Senior Member

    I buy from AENOR, which is the Spanish branch of the ISO Org. They do not allow me to buy the original version because I live in Spain. I can't but buy the Spanish version, which also has translation errors !!!!.
    I can address them, I have done so on other occasions, for other issues, and they do not pay any attention. But what worries me now is that an author ignores the consequences of making such an impractical product (even if he has not charged for it) and that the product is so bad that the errors or difficulties that it entails for the user, result in an economic benefit for the author. It is inconceivable.
     
  9. Alan Cattelliot
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    Alan Cattelliot Senior Member

    I must say that some of us have already received this king of email . FIN stand for Federation des Industries Nautiques (Fr), the sender is talking about the pain he has in the ***, being obliged to buy the standards he has worked on for 20 years. Bold characters, underlined characters, capital characters, Exclamation for final point. Eloquent testimony of what kind of frustation it can be to be invested in such enterprise as building a standard. Pure Poetry.

    Bonjour,
    Par la présente , je vous informe de mon indignation quant au fait qu’après été membre de différentes commissions, avoir investi pendant plus de 20 ans des centaines d’heures d’étude, fait effectuer des stages, participé a nombre incalculables de réunions, a l’aide a l’élaboration des normes de structure/Gréement/stabilité , nous sommes obligé de payer celles-ci a la FIN sous forme d’abonnement, ce qui est encore plus cher que le CD de la norme 2013.
    CECI EST ABSOLUMENT INSUPORTABLE ET INJUSTE !
    Je ne suis pas le seul a le penser…..
    Dans le futur vous trouverez vous-même d’autres partenaires pour travaille gratuitement.
    Pour cette raison , nous ne nous réinscrirons plus à la FIN qui a notre sens ne remplis absolument pas son rôle.
    Je vous charge de mettre en copie a ces messieurs de l’ISO !


    For our subject, I've noted these very interesting remarks from our conversation. As I said, I wish to give a hand, if possible, if accepted, if correct, if not stupid, if your mother wears blue socks.

    The ISO12215-5:2019 is faulty standard, where the samples provided in Annexes do not match the same calculations performed by the users / agree example to be made

    The same problem we experienced with ISO12215-10 / agree example to be made

    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. / Disagree proof to be made

    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 / agree example to be made

    their use is totally impractical / Disagree proof to be made

    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 / agree proposal to be made

    Thus, the standards should produce clear recommendations, and not guesses or interpretations / agree proposal to be made

    Many of us know that the nail is nailed with a hammer but we do not know what the nail looks like. / agree proposal to be made

    Now it looks like instead of set of mechanical tools to hit the nail, we are given book to read on theory of the nails. / agree proposal to be made



    And remember. ISO rules are the kingdom of consensus. That means that the more people are favorable/against an idea, the more priority will be made to keep/reject subsequent proposals.
     
  10. Alan Cattelliot
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    Alan Cattelliot Senior Member

    I've also noted very hard these two prominent question, which demand answers :

    Is there something in this standard that improves the normal procedures, with much more than 20 years of validity, of the calculation of composites?

    What do you propose in the standard for layered analysis?
     
  11. TANSL
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    TANSL Senior Member

    As I have been the one who has asked this rhetorical question, I will proceed to answer. In the first place, that text, taken out of its context, loses absolutely all its meaning. That is a very crude "trick", a trap I will not fall into. When I ask that rhetorical question (rhetorical since I have read the standard and know perfectly what it says in it) I mean that it is precisely spreadsheets that are reproduced in it even though it seems to you that this computational instrument does not it deserves no credit. And I say it seems because I thought I detected a certain unpleasant tone when you say "I won't be of any danger for your xls spreadsheet."
    I am the first, and I suppose that there are many more people who will think the same as me, in thanking the enormous efforts that you, and some others, for more than 20 years, and without charging a penny, have made to devise a standard that It should be the beacon that floods us all with its light. I understand your frustration that no one appreciates that effort, that no one thinks it was worth it. I really understand. Now, please, make an effort to understand the frustration that those of us who, without knowing the tremendous effort behind it, have received into our hands, paying a not small amount, a thing that is a monstrosity. If you, in more than 20 years of strenuous effort, have not been able to do otherwise, why do we have to ask for forgiveness?
    If, in addition, we see that, recognizing the shortcomings of this norm, future services are offered to help manage it, our perplexity, at least mine, is immeasurable.
     
  12. Alik
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    Alik Senior Member

    We are using FEA Strand7 for composite and metal structures, mainly for:
    - global strength study
    - strength of details, such as jet drive supporting structure, engine base, lifting points, etc.

    While using it for local strength, we found man-hours excessive. The same task can be done with use of spreadsheet much faster. The issue is: with existing approach to load definition on panels and stiffeners and safety factors, FEA is used to replicate results of 'lower-tech' methods.

    There should be some real weight saving to use FEA for local strength; right now we don't see such saving. Moreover, stress concentration points and modelling simplifications will make the FEA results worse than spreadsheet results.
     
  13. Alan Cattelliot
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    Alan Cattelliot Senior Member

    FEA implementation in the standard has not be easy. The idea was to open the door to most sophisticated methods to address, in the standard, unsupported parts or assemblies that have major role in the structural integrity of very taylored boat with complex metallic shapes receiving efforts in many direction. In conjuction with the part10, it could also allows a more sophisticated design of multihulls, because since yet, as I know, the multihulls under 24m were supposed to be compliant to the part5 only. As a result, builders were obliged to make boats heavier - and are still today bound to this - to comply with the standard, which is also man-hours excessive.

    It has also been implemented to take account into the curved shapes that comes out of plastic products, and which were most of the time very difficult to control with the standard method, giving a vast majority of times non-conformities in the final assessment. Although everyone knows that there were no danger with the offered composition, builders were to endure DoC with reserve, offering to much frontal area to national or class registers for annoying questions and blockages of anykind.Which is also man-hours exessive.

    Such positions should not last long before you get flat tires to your car.

    There are several factors that explains why method1 and 2 could not give good results in the situation of curved panels, and the FEA proposition, in this case, can to deal with 2 of them in the same time : the geometric stability and the unbalanced ply composition with phenolic resin felt embedded. (The CLT method could deal solely with the second one). In the same time FEA could be used in conjuction with the part10 to take account into local loads besides the hydrostatic pressure. And FEA could also be used exactly the way you are using it, to have a detailed view of very important zones.
     

  14. Alan Cattelliot
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    Alan Cattelliot Senior Member

    And, Mr. TANSL

    I find a little "pinchy" the way you speak. You know very well what to do with the standard or not. You know very well what is not good in the standard or what is acceptable. You know very well how to provide services based on the knowledge you have because of your experience and the choices you have made, among others. The standard has been checked by ISO in many ways, preventing any proprietary content inside. All informations have reference, and it is just up to you to dive into the standard, with a very, very, very good attention.
    I doubt that any of my remark would show up a secret lecture inside the text. Every conclusion i have, you have it already.

    So, please...
     
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