ASME provides fundamental design guidance for 3D printing


ASME provides fundamental design guidance for 3D printing

New standard leads to smoother production in 3D printing

Posted: Wednesday, July 6, 2022 – 12:03 PM

SSince the 1940s, engineers have used a common design language (a set of definitions, symbols, and practices) to write technical drawings that can serve as clear manufacturing plans or inspection checklists.

While this system still works well for many traditional manufacturing methods, it has not equipped engineers to produce clear and consistent design documents for additive manufacturing, commonly referred to as 3D printing. This lack of standard communication methods risks losing information about 3D printing designs during translation.

The American Society of Mechanical Engineers (ASME) has released an updated standard, based largely on research from the National Institute of Standards and Technology (NIST), that includes language specific to 3D printing. The ASME standard, titled Y14.46—“Product Definition for Additive Manufacturing,” identifies important characteristics unique to 3D printing and describes how they should be documented.

The tips could help engineers from a wide range of industries communicate more effectively with manufacturers, product inspectors and others. Its widespread adoption could remove a persistent barrier to the application of 3D printing on a larger scale, potentially unlocking the environmental and economic benefits associated with the technology.

“The industry is currently in the midst of a digital transformation, moving away from physical 2D drawings, and additive manufacturing is one of the catalysts as it requires digital 3D models,” says Fredric Constantino, ASME Project Engineering Advisor. “And if you’re working on one of those models, this standard will guide you to make it understandable to both 3D printers and other people.”

These 3D models have many unique degrees of freedom offered by additive manufacturing, also known as 3D printing, such as the production of parts with complex geometry and composed of several materials. A new ASME standard, Y14.46, provides guidance on how to relay specific 3D printing considerations into design documents. Credit: reprinted from ASME Y14.46-2022

With subtractive manufacturing, a common production method, machines cut parts from blocks of raw material according to instructions, which can be described in a digital or physical 2D drawing. In contrast, additive manufactures take shape from scratch, as printers produce one layer at a time, fusing them into a predetermined shape that can only be dictated by a 3D model.

In addition to producing less waste than subtractive methods, 3D printing also allows for more complex designs, such as those that are not completely solid but partially hollow and filled with a mesh that can take many shapes.

“Additive manufacturing has opened the door to many unique design opportunities for engineers, but this freedom also creates challenges in communicating complex designs,” says NIST mechanical engineer Paul Witherell.

The lack of consensus on how to convey aspects of a product related to distinct 3D printing capabilities has blurred communication between different organizations and created a barrier to more widespread use of the technology.

ASME responded to this roadblock in 2014, forming a committee of several dozen engineers from industry, academia, and the federal government. The group, co-led by Witherell until 2019, sought to produce a uniform approach to defining 3D printed products.

“We weren’t looking for ad hoc solutions; we were looking for solutions that could be standardized and implemented by the community to address these communication challenges,” says Witherell. “We already know that we can make good parts using additive manufacturing. Now the goal is to make a lot of parts with additive manufacturing, and that’s a necessary step.

The committee developed the standard over several years, drawing on input from 3D printing experts and NIST research. They also incorporated feedback on a draft version of the standard published in 2017.

With the new guidelines, the group is introducing concepts to address not only the nuances of 3D printing designs themselves, such as their potentially complex internal geometry, but also the particularities of the printing process. Factors including the orientation of a print and whether temporary structural supports are printed can influence the strength, durability and other properties of the final product.

Since printers need digital product information to be presented in a particular way, the guide also includes a section on how to package data based on 3D models so that it is machine readable.

Designers are expected to reference the new standard as well as several previously established standards, which cover basic design considerations relevant to a wide range of manufacturing methods.

3D printing has several clear advantages over more established manufacturing methods, but it hasn’t been implemented to nearly the same degree. One reason for this is the lack of a fundamental way to get design ideas across, a gap now filled through the efforts of ASME and NIST.

If adopted by major manufacturing players, the standard could improve communication for 3D printing, potentially creating a more sustainable and efficient manufacturing industry in the future. However, expanding the standard along the way will be essential.

“Some of the other ASME standards last 10 years, 20 years without revision, but additive manufacturing is advancing so rapidly. We aim to keep pace by adding to this standard over time,” says Constantino. “We expect him to evolve quickly.”

For more information, visit ASME’s Additive Manufacturing Collection and NIST’s Measurement Science Program for Additive Manufacturing.

First published June 9, 2022 on NIST News.

Abdul J. Gaspar