The International Association of Classification Societies (IACS) has published a new recommendation, Rec.186, that meets the need for a standardised approach to integrating Additive Manufacturing (AM), commonly referred to as 3D printing, into marine and offshore applications.
The maritime industry continues to embrace developments in manufacturing technologies to enhance efficiency and sustainability in shipbuilding and offshore operations. Additive Manufacturing (AM) has emerged as an alternative to traditional manufacturing processes by fusing materials to produce objects from a digital 3D model into a series of 2D cross sections for layer-by-layer physical prints, ultimately producing a 3D object. Unlike conventional methods such as casting, forging, and welding, AM offers greater design freedom, reduced material waste, and the potential for on-demand production. Its flexibility allows for localised production and customisation, providing tailored solutions for specialised marine and offshore applications.
‘Rec. 186: Additively Manufactured Metallic Parts for Marine and Offshore Applications’ establishes a framework for the qualification, approval, and certification of additively manufactured metallic parts. This recommendation provides detailed guidance for key aspects of the AM process, including part design, feedstock selection, AM processes, post-processing, and inspection/testing. By incorporating recognized international standards such as ISO/ASTM 52900 and AWS D20.1, it aligns AM technology with existing Unified Requirements, particularly UR W for materials and welding, ensuring equivalent reliability and safety.
To facilitate the safe and effective adoption of AM in the marine sector, the recommendation outlines the following key areas:
Scope of AM Process: The recommendation covers Powder Bed Fusion (PBF), Directed Energy Deposition (DED), and Binder Jetting (BJT), with detailed process-specific parameters.
Criticality Levels and Testing: Introduces tiered testing levels (AM Levels 1-3) for class and certified items, enabling customised testing based on application criticality.
Feedstock and Material Standards: Specifies rigorous qualification processes for AM feedstocks, including powder, wire, and binder feedstocks, including recycling protocols for sustainability.
Part Design and Qualification: Includes innovative provisions for design optimisation, topology adjustment, and pre-build simulation to ensure robust performance under marine conditions.
Inspection and Non-Destructive Testing (NDT): Addresses anisotropic properties and potential imperfections (e.g., porosity, lack of fusion) through advanced NDT methods like CT scans.
Rec. 186 establishes a robust verification and certification framework, ensuring the safe and effective use of AM technology in critical marine contexts. Moving forward, IACS will continue to collaborate with stakeholders to expand the application of AM in safety-critical marine components. By encouraging shipyards, original equipment manufacturers (OEMs), and vessel operators to adopt AM, it paves the way for innovation in shipbuilding and offshore engineering, marking a pivotal step in the safe and standardized adoption of additive manufacturing.
Commenting on the publication of Rec. 186, Alexandre Astruc, Chair of IACS’ Expert Group on Materials & Welding, said:
“Additive manufacturing, or 3D printing, is increasingly becoming a valuable tool for the marine sector, offering a flexible, speedy and customisable solution for environments where the consequences for safety, sustainability or operational uptime can otherwise be significant. While its potential for rapid production is notable, its true strength lies in its ability to provide innovative, on-demand solutions tailored to complex maritime challenges. In developing Rec 186, IACS is seeking to safeguard the benefits offered by additive manufacturing by ensuring it is underpinned by a standardised framework for verification and certification that gives confidence to all parties.”
Source: IACS
