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Additive Manufacturing Certification Guidance Notes

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Mon, 18 May, 2020

TWI and Lloyd’s Register (LR) have worked together to update the guidance notes for the certification of products produced using additive manufacturing (AM) processes as well as the qualification of AM facilities.

The guidance notes were first published by TWI and LR in January 2016, with the aim of helping manufacturers to establish the safety of 3d printed parts. The notes were updated in 2017 and this latest version of the guidance notes reflects the changes in technology over the last three years.

The guidance notes provide goal-based guidelines for the certification of parts produced using AM processes including powder bed fusion by laser or electron beam, directed energy deposition by laser, and wire plus arc additive manufacturing (WAAM).

AM is being used by an ever growing number of businesses to manufacture components for a wide range of industries, including aerospace, construction, energy, medical, marine and offshore.

David Hardacre, LR Lead Specialist, said, “Many businesses have used the previous guidance notes from LR and TWI to great effect. They’ve been designed for any business interested in starting their AM journey that needs to understand how qualification and certification requirements compare with conventional manufacturing processes – or for those who are already using AM and want to qualify their processes or certify their materials and/or parts. They’re also valuable for those organisations who sub-contract any element of their manufacturing to a supplier using AM, so they can understand what’s required for certification.”
AM certification provides confidence by ensuring that businesses can verify the safety of products to protect operators, assets, the environment and the general public. The provision of product assurance means that legal requirements have been met and that AM parts are suitable for intended applications. The certification also demonstrates the capabilities and quality of the parts to customers and end-users.

Paul Goodwin, PPL and PBF Lead at TWI said, “AM processes are increasingly being used in industry, but the uptake has been hindered by a lack of understanding of how to control the quality and reproducibility of the parts made and how to qualify and certify these parts for use. These guidance notes are designed to help chart the way through what can at times appear to be a confusing set of requirements and to establish what the appropriate requirements for certification are.”

TWI and LR have a history of working together over several years, often alongside third parties such as the Singapore Centre for 3D printing at Nanyang Technological University (NTU Singapore) and Rolls Royce Nuclear.

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