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Sprucken och tappad köl – Bavaria svar 2

16 juni, 2010 – 16.38 Kommentarer inaktiverade för Sprucken och tappad köl – Bavaria svar 2

På Kryss gav varvet och Bavarias återförsäljare i Sverige Bavia möjligheten att besvara kritiken från ägaren och den metallurgiska undersökningen i denna artikel i På Kryss (nr 5/6-2010).

Dear Mr. Tiberg, in the following as announced my overall statement, which deals with both the legal assessment under German law and the question, to what extent the rupture of the keel is to be attributed to a material defect. Let me begin with the second aspect: 

1. Your client refers the loss of a part of the keel and the reproach that Bavaria used and still uses ”mortal dangerous cast iron keels”, to a material analysis of Professor Fredriksson, Stockholm. This analysis allegedly clarifies a basic defect in the material composition what released a growing corrosion with the final consequence that the lower part of the keel has falen off, and the upper part has remained fixed to the hull.

As far as Professor Fredriksson refers the rupture of the lower part of the keel to incorrect material composition in chemical regard, then this starting point is not comprehensible in several aspects and cannot be accepted by Bavaria.

Starting point of an adequate technical and chemical evaluation is the fact that the keel was manufactured in grey cast iron, that is cast iron with flake graphite with the material abbreviation EN – GJL – 250 according to the DIN EN 1561. According to the DIN EN 1561 both the tensile strength and the hardness of the cast iron material are constituting the crucial criterion. Neither the DIN EN 1561 nor the comparable old German DIN 1691 give guidelines as to the chemical composition of the grey cast iron material in general respectively of the grey cast iron material with the material symbol EN-GJL-250 in particular. Only regarding the tensile strength and the hardness concrete and binding standard values are given. According to the DIN EN 1561 the producer of the grey cast iron has to focus on the tensile strength and hardness as the crucial manufacture criterion, whereas the chemical composition is open to his disposition within noncommittal minimum and maximum limits given by the state of the technical art. This limits cover however a very far range, which deviates substantially from the Professor Fredriksson?s specifications.

That means, has the grey cast iron the tensile strength and hardness prescribed according to the DIN EN 1561, the chemical composition is secondary.

It is indeed amazing that Professor Fredriksson ignores the European DIN standards, and this all the more, than Sweden is already for a long time member of the European Union and thus the regulation of the European legal DIN are obligatory standards in Sweden, too.

A consultation with the producer of the keel confirmed that all to Bavaria and other boat manufacturers delivered grey cast iron keels with the material symbol EN-GJL-250 (GG-25) displayed a by far suffient tensile strength and hardness demanded according of the DIN EN 1561. This was verified and determined both immediately after the production of the keel and in context with the outgoing inspection. In addition, the permanently accomplished charge analysis on the basis of the molten material confirmed that the chemical composition of the grey cast iron laid within the limits, given by the state of the art.

We attach an evaluation of the charge analysis from the period between that 19.11.2005 to 25.11.2005, thus from the period, in which the keel for your client?s yacht was manufactured.

In context of a chemical analysis of the cast iron material it is first of importance that cast iron technically is considered as a ternary Fe-C-Si alloy, whereas iron (Fe) is its key-element (ca. 90 – 95 % wt) and carbon (C) and silicon (Si) are its main alloying elements. These three main elements are in general — but must not – accompanied with further elements, like manganese (Mn), phosphorus (P), sulfur (S), copper (Cu), chrome (Cr) etc., whereby these accompanying elements generally do not have any effects regarding the tensile strength and hardness of the cast iron. According to the state of technical art standards for alloying part of carbon, silicon and manganese were developed with the following minium and maximum threshold values:

C: 2,90 – 3.70% wt
Si: 1,70 – 2.50% wt
Mn: 0,35 – 1% wt

So far the common threshold values for these DIN EN 1561 – materials with the material symbols EN-GJL-150, EN-GJL-200, EN-GJL-250 and EN-GJL-300.

By way of comparison we refer for instance to standards given by the American Society for Testing and Materials International (ASTM). Thereafter the threshold values are for carbon 2 – 4% wt and for silicone the 1 – 3% wt. ASTM A48 recommends for grey cast iron planning targets as follows: C = 3.4 %wt, Si = 1.8 %wt and Mn = 0.5 %wt. Regarding further elements no defaults are made.

By the way I want to point out, that the main alloying elements C, Si, Mn as determined both by Prof. Fredriksson and your client in his ”Press Release” are located within the afore mentioned limits. In addition, the results of the producer?s charge analysis from the melt, with which the keels were manufactured later for Bavaria, are within the state of the technical art limits.

As far as both in the charge analysis of the manufacturer and in the context of the statements by Professor Fredriksson the concentration of manganese is borderline, you cannot derive any profits out of this fact, for the limits are not absolutely binding and concede certain extent tolerances. In addition to it is again gotten straight that the main elements are Fe, C and Si anyhow as already explained in detail.

After all the grey cast iron used for the production of the keel is absolutely confirm to DIN EN 1561 as to the required tensile strength and hardness. In addition it becomes obvious that the material composition is in total agreement with the standards given by the state of technical and chemical art. Thus your client?s assumption a material defect caused the rupture of the keel turns out to be without any substance and has to be rejected by Bavaria. On the contrary Bavaria and the keel?s producer are profoundly convinced that the rupture has its basic cause in the pre-existing defect occurred in spring time 2007 (”deep crater”).

2. The used grey cast iron keel according to DIN EN 1561 with the material designation EN-GJL-250 also is in line with the so called ”EU sport boat guideline (RCD)”, [EU Recreational Craft Directive 94/25/EU], what is confirmed by a special certificate of the International Marine Certification Institute (IMCI). We refer insofar to the certification document as to the type of boat Bavaria 39Cruiser. We assume that this certification document was handed over to your client when he bought the boat. By the way this certification document is part of the manual, which is handed over to each buyer by Bavaria and which surely was handed over to your client in the context of his second hand purchase.

Also it has be pointed out that up to now Bavaria has built cast iron keels with the material designation GG-25 and/or EN-GJL-250 several 10,000 times into its yachts without any rupture in comparable form – different it was only in case of an external forceful impact onto the keel as obviously occurred with your client?s yacht. Also Bavaria obtains the cast iron keels of the same manufacturer for many years.

Moreover such cast iron keels with the designation EN-GJL-250 are used by further large European yacht manufacturers, in particular of the French shipyards Jeaneau and Beneteau, what brings to proof that Bavaria is acting within the relevant EU-Directives and the rules specified by the state of technical art concering boatbuilding, when using cast iron keels manufactured according to DIN EN 1561 – EN-GJL-250.

For these reasons it is in no way comprehensible, that your client argues untruthfully in his ”Press Release”: ”Bavaria is using mortal dangerous cast iron keels!” In this connection we refer for the avoidance of repetitions to our remarks in our email letter of November 25th, 2008, 14:43.


A marked photo documentation annexed to your client?s ”Press Release” confirms that accurately at the centric location of the fracture line an external damage (”deep crater”) has occurred in former times and that this damage was repaired in the spring 2007. Bavaria contradicts your client?s statement of a proper repair and refers to your client?s photo and to an attached photo, which show the site of fracture in plan view. Both pictures make clear that where the crater was found several external and interior tears have its starting point. With such damage findings, which only can be attributed to a violent application of force, the keel could not have used any longer and must have been replaced by a new one. By the way the damage symptoms suggest that the repair of the crater could not have been duly prepared and accomplished, otherwise the interior tears must have been discovered. Further substantial doubts exist whether the keel with substantial damages and tears was duly examined with ultrasonics. If this would have happened, then the tears and interior damages would have been discovered at any time. In cases, in which via an application of force a recognizably damage of the keel took place, it corresponds with the rules of the technology that this keel must be examined by ultrasonics as to further damage and tears.

Attached is further a photo that shows the location of fracture in enlarged view. This picture assures that the cast iron material is homogeneous and contains no inclusions, which possibly could be responsible for a break. The homogeneous appearance of the material also allays any doubts as to an adequate chemical mixture and composition.

As far as Professor Fredriksson means, an incorrect material composition caused corrosion, what finally was cause of the rupture of the keel, we refer to the state of the technical art, where upon any injury of the cast-iron?s skin, which is confirmed by the admitted damage – ”deep crater” – araises corrosion phenomena. If now it is assumed that actually, as Professor Fredriksson means, the rupture is the result of a corrosion, then only the pre-existing damage – ”deep crater” – of the keel is the exclusive source of the corrosion and thus responsible for the keel?s rupture.


With his letter of November 5^th , 2008 your client claimes an amount of ca. 25.000,00 EUR from Bavaria. Please grant me the question after the legal basis of these claims?

Regardless of any legal basis any warranty as to the keel must legally be regarded as expired in view of the pre-existing defect of the keel, which neither Bavaria nor a Bavaria dealer had the chance to examine and or to repair. This the more as the damaged keel – ”deep crater” – obviously was not examined by ultrasonic and more over not repaired after the state of technical art. This is also of relevance in legal and technical respect when the cause of the rupture assumedly must be seen in a corrosion, for the admitted deep crater inmidst of the keel was in each and every case precondition for any corrosion phenomena.

For this reason Bavaria recommends that your client contacts the seller of the yacht in order to assert his possibly existing warranty claims. However a condition would be that the keel was damaged with the ”deep crater” in the period before your client bought and used the yacht, that means the damage must have taken place when the boat was still in the property of the seller.

Finally I ask for understanding that in view of the mentioned facts Bavaria is not in the position to accept and acknowledge your client?s claims for indemnification amounting to ca. 25.000,00 EUR. In this connection your client should recognize that Bavaria already made a new keel at his disposal and this free of charge. This good will, I want to point out, was granted without any acknowledgement of a legal obligation.

With kind regards

Hagen Stock


Dr. Hagen Stock & Kollegen

Hauptstraße 23, 97199 Ochsenfurt

Telefon: 09331/9818-0

Telefax: 09331/9818-18

e-mail: stock.rae@t-online.de