DNV GL is a quality assurance and risk management company that helps businesses obtain safety and sustainability through classification, certification, and other services to a wide range of industries, including the maritime, oil and gas, power, and renewables industries. The company has been frequently involved with 3D printing lately, particularly in the maritime arena, and now it has published the first classification guideline for the use of additive manufacturing in the maritime and oil and gas industries. The classification guideline is intended to ensure that parts produced via 3D printing, and the materials from which they are printed, have the same level of quality assurance as those produced by traditional means.
“We have been investigating the potential of 3D printing for the maritime and oil & gas sectors since 2014. With the introduction of the class guideline DNVGL-CG-0197, DNV GL is now ready to certify and support our customers and industry stakeholders to take advantage of this rapidly maturing technology. It will give end users confidence in the products and allow suppliers to offer their technologies and products for use in vessels and offshore installations,” said Marit Norheim, Vice President, Material Specialist, Hull, Materials & Machinery at DNV GL – Maritime.
The WAAMpeller was the first 3D printed ship’s propeller to be class-approved. [Image: Damen Shipyard Group]
The classification guideline is particularly important in regards to metal 3D printing, which is becoming more frequently used in the maritime and oil and gas industries. It has been used to produce a number of parts, including screw pins, bearing shells, box heat exchangers and propellers. Metal has more safety concerns, both during printing and after parts are completed, and the quality of the powder and the finished part are critical to safe operation of marine and oil and gas applications. With the proper guidelines in place, manufacturers can benefit greatly from the use of 3D printing.
“Additive manufacturing means products and components can be printed according to local needs, or even on board ships and offshore installations,” said Knut Ørbeck-Nilssen, CEO DNV GL – Maritime. “This equates to less lead time, less cost, less labour, less logistics, and less need to keep stocks of spare parts. AM can also be used for maintenance and repair, simply adding layers of material to worn components, thus negating the need to replace them.”
By creating the classification guideline, DNV GL has provided a pathway for additive manufacturing certification and has processes in place to assess every piece and stage of the additive manufacturing process, from materials used, to a technology assessment, manufacturing procedure qualification, data transfer, 3D printing and post processing.
3D printed aluminium replica of a mooring chain testing bed at the DNV GL lab in Bergen [Image: DNV GL]
“AM parts that perform the same functions as those produced in traditional manufacturing environments must offer the same levels of quality assurance. Similarly, the companies that have designed the parts must protect their intellectual property, so that customers can be sure they are receiving genuine products that are guaranteed fit for purpose,” said Norheim. “This is why this guideline is so important to all industry stakeholders.”