ISO 15401:2000 pdf download

ISO 15401:2000 pdf download.Ships and marine technology – Bulk carriers -Construction quality of hull structure.
4.3 FittIng and assembly
4.3.1 Fitting and assembly of parts and members
4.3.1.1 The accuracy requirements of block assembly shall be met for the fitting and assembly of parts and members. Protective primer shall be repaired after welding.
4.3.1.2 Special attention shall be paid to the following points of quality control:
a) geometrical dimensions of parts and members;
b) installation locations;
c) excessive gap before welding;
d) deformation.
4.3.2 Block assembly
4.3.2.1 Block assembly should generally be carried out on a platform or jig.
4.3.2.2 Pre-outtitting of parts and members shall be done according to applicable design drawings.
4.3.2.3 The accuracy that meets the requirements given in the following pages for general assembly shall also be met for block assembly.
4.3.2.4 Block assemblies may be coated after inspection.
4.32.5 Special attention shall be paid to the following points of quality control:
a) marking accuracy;
b) installation accuracy of internal structure joints inside the block;
c) accuracy of block configuration and its dimensional size;
d) accuracy of block edges;
e) correctness of assembling reference lines;
f) flatness of face plate and location deviation of main engine bed;
g) installation locations of key components, such as shaft boss, rudder horn, etc.
4.3.3 Erection on shlpway/dock
4.3.3.1 Marking on the shipway/dock shall be carried out with corresponding symbols and marks.
4.3.3.2 Placing the reference block in position, and then proceeding with successive blocks shall be done according to the shipway/dock assembly schedule.
4.3.3.3 During the construction process, all temporary openings in strength members and their closing-up shall comply with the requirements set out in the applicable construction drawings and/or standards.
4.3.3.4 Removing temporary welding pieces and lifting eyepieces shall be done according to usual practice (refer to Table 37).
4.3.3.5 After completing shipway/dock assembly, the hull shall be coated or the (block) coating repaired according to specified requirements before launching.
a) accuracy of marking on the shipway/dock;
b) correctness of location of the reference block:
c) frame spacing at block junctions;
d) alignment accuracy of structural members:
e) straightness of base line;
f) alignment accuracy of propeller shaft centreline;
g) marking accuracy of loadline and draft marks;
h) principal dimensions of the hull.
4.4 Welding
4.4.1 Preparation before welding
Welding materials, preparation of weld joints and assembly accuracy shall comply with classification society requirements set out in quality control documents.
The welding zone shall be free of rust, scales, grease, moisture or other dirt.
The environmental condition of the welding area shall be kept in good order.
Tack welding shall be carried out according to specified technological procedures.
Wherever new materials or new welding technologies are adopted, test reports and welding procedures shall be submitted to the classification society for approval.
4.4.2 Welding process
All welding shall be carried out according to the methods and conditions as required by the welding technology procedures. Proper measures for minimizing welding deformation shall be taken.
4.4.3 WeldIng inspection
4.4.3.1 Inspection of welding shall be carried out throughout the whole process of welding including inspections before, during and after welding, as well as the inspection of finished weidments.
4.4.3.2 All welds shall be visually examined first.
4.4.3.3 Quality inspection of welded seams shall be carried out according to specified requirements. Either X-ray detection, ultrasonic detection or other inspection methods approved by the classification society shall be adopted.
4.4.3.4 Leg sizes (leg length and throat depth) of fillet welds shall comply with the design plan and relevant codes as approved by the classification society.
4.4.3.5 Welded Joints on the strength deck, shell plate and interior strength members in the mid.length region shall be inspected in accordance with the non-destructive inspection plan approved by the classification society.
4.4.3.6 Welds not conforming to the requirements of quality standards shall be rectified and repaired, and shall be inspected again.