|
1. Objective
1.1. The rules in this chapter deal with the production of steel craft. A prerequisite for applying
the rules in this chapter is that the raw-materials, the structure and scantlings meet the requirements
in Chapters 16, 17 and 18 respectively. The rules apply to individually built boats and, as applicable,
to series built boats.
2. References
2.1. 2.1. This chapter is partially based on international standard ISO 12215-4 - Small craft — Hull construction and scantlings —Part 4: Workshop and manufacturing.
- EN 9606-1:2002. Qualification test of welders. Fusion welding. Aluminium
and aluminium alloys.
- EN ISO 15614-2:2005. Specification and qualification of welding
procedures for metallic materials -- Welding procedure test -- Part 2: Arc
welding of aluminium and its alloys
- SFS-EN ISO 10042: Welding. Arc-welded joints in aluminium and its
alloys. Quality levels for imperfections.
- EN-ISO 5817:2006. Welding. Fusion-welded joints in steel, nickel,
titanium and their alloys (beam welding excluded). Quality levels for
imperfections
- SFS-EN 970: Non-destructive examination of fusion welds. Visual
examination
3. Documentation
3.1. To verify the compliance with the requirements in this chapter, a production report for each
individual craft is to be prepared. The report shall be readily identifiable by means of the
Craft Identification Code, the yards' newbuilding number or similar and shall include the following
information as relevant::
- Reference to the used structural drawings, see Chapter 18;
- The material certificates for plates, profiles and welding consumables;
- The qualification certificates of the welders which have participated in the welding of the hull;
- Protocol of visual inspection of welds;
- Reports of radiography and/or other NDT inspection carried out;
- Reports of possible problems encountered during production and the remedy;
Page index
4. Workshop conditions
4.1. Steel plates, profiles, and other steel materials shall be stored such that corrosion or deformation will not occur.
4.2. Welding consumables shall be stored in a dry and clean location.
4.3. Welding of stee shall not be carried out at temperatures below -5 oC.
Page index
5. Materials
5.1. It shall be possible to show, with the aid of material certificates,
that the plating and profiles which are used in a particular craft, are of the
type specified on the construction drawings.
5.2. The material shall be straight and undamaged, and of the dimensions
and alloy specified on the approved drawings.
Page index
6. Shaping of materials
6.1. Where cold shaping is required, care shall be taken to avoid local damage to the material.
6.2. Bending of plates shall be carried out by rolling. The bending methods and the bend
radius shall ensure that excessive local strain leading to cracks in the material does not occur.
Page index
7. Welding
7.1. Welder's qualification
7.1.1. Welding shall only be carried out by qualified persons. In craft of design category
A and B an official welder's qualification according to SFS EN 282-1 or equivalent standard is
required. For craft of design category C or D, the qualification may be assessed by the beforementioned
test or by independent assessing of the welds at the workshop.
7.1.2. In general, MIG or TIG welding methods shall be used. Other methods may be utilised if it
can be demonstrated that the results is at least as good as for welds carried out with MIG or TIG..
7.2 Welding Procedure Specification
7.2.1. In the manufacturing of craft of design category A and B the welding shall be carried out in accordance
with welding procedure specifications (WPS) tried out prior to the construction and which are demonstrated to
result in welds with adequate quality. Welding procedure specifications shall be prepared for all relevant joint
types, welding positions and material thicknesses and with the welding machines to be used for the construction of
the craft. The welding procedure specifications shall be carried out in accordance with the standard EN ISO 15614-1.
For craft of design category C and D no formally approved welding procedure specifications are required.
7.3. Surveys
7.3.1. Welding is to be carried out in accordance with the drawings.
7.3.2. The welds in the hull, deck and other critical structures are to be visually inspected according to EN ISO 970.
7.3.2. In addition, for craft of design category A and B, inspection by radiography shall be carried out.
The sampling is to be decided on basis of the visual inspection.
7.4. Required weld quality level
7.4.1. The quality level of welds in all load-bearing structures shall be at least C according to the standard ISO 5817.
This applies to the following items:
For all crafts hull including:
- Plating and transom;
- Keel and stem;
- Bulkheads, webframes, stiffeners;
- Engine foundations;
- Other stiffeners and foundations.
Additionally with decked and closed crafts:
- Deck stiffeners;
- Super structures and their stiffeners;
Page index
|
