GL Publishes New Rules for Materials

The revised and expanded Rules for Materials and Components have been published by Germanischer Lloyd (GL). The Rules define the properties of various metallic materials and lay down the requirements for the production processes and the manufacturers. The prerequisites and conditions for the corresponding approvals are also stipulated. For the manufacturers and suppliers of materials and components intended for use on GL-classed ships, the Rules of Germanischer Lloyd form an essential prerequisite. The new edition has been updated to reflect current technical standards and new codes, with improvements in the cross-references.

To a large degree, the construction of ships, engines and their components depends on materials such as steel, aluminium and copper. The dimensioning of the ship and its components and therefore also the level of safety is greatly influenced by the properties of the materials used. The defined characteristics and their reproducible quality make stringent demands on the manufacturing processes and the technical qualifications of the manufacturers. Certification is used to verify the required properties. Continuous monitoring of the relevant processes and the safeguarding of defined quality characteristics is thus also a major factor in the availability and longevity of the structure.

The new edition of the Rules for Materials covers, for ferrous materials, the requirements for rolled products, pipes, forgings, cast steel and cast iron, fittings and pressed parts, as well as anchors, propellers, chains and accessories. The material properties of the hull and engine applications are specified, including the use at high or low temperatures and with certain corrosive media. In addition, the requirements are set out for components made of aluminium and copper alloys.

The Rules for Materials form the basis for the hull structure and all ship and machinery components described in the Construction Rules of GL, e.g. components for the steering gear and propulsion plants and for diesel engine parts. Certain requirements of GL that had until now been listed in separate standards were incorporated directly in these regulations, so the user need only refer to the GL Rules when working on GL projects. Comprehensive information on the non-destructive testing of forgings and castings was included for the first time. Besides requirements for the testing equipment and the execution of the tests, drawings are used to illustrate the subdivision into test zones and to describe the approval criteria for the corresponding components.