Digitalization & additive manufacturing

Features - Cover Story

Leveraging the real and virtual worlds.

February 24, 2022

Figure 1
All photos courtesy of Siemens Industry Inc.

Additive manufacturing (AM) has evolved from 3D printing for prototyping with basic materials and equipment to producing low-tolerance components with limited-use to AM today – a highly complex, high-accuracy production technology that competes as a viable alternative to traditional chip-cutting or injection molding. The evolution of hardware and software is removing barriers, enabling machine builders and users to adopt AM technologies in their factories and on their shop floors. It represents a significant development on the road to digitalization.

Market opportunities

AM is relevant in a wide range of industrial applications and opens a myriad of opportunities for manufacturers. Companies can reimagine their products with reduced weight and material consumption, realize a digital transition from scan to part, and rethink their business or reinvent their manufacturing. Product transformation happens by moving from conventional designs to designs specifically for AM, and other realities quickly become apparent. These include practical, cost-effective one-off production; maintaining zero inventory in certain industries with on-demand production; adopting a design-anywhere, print-anywhere mindset; and accelerating innovation cycles. A company can eliminate molds, castings, and tooling; dramatically reduce or eliminate assembly processes; reduce supply chains; and move to flexible, low-volume production at workable margins. Additive also offers the freedom of printers running mostly unattended.

A reality today

Another advantage to 3D printing is a manufacturer can quickly get the part in their hands and see it in form, fit, and function modes. They can make an adaptation and quickly print it again.

Figure 2

Aerospace case

A recent example is an aviation fuel injector. This project took several years but started with 21 individual machined cast and fabricated components welded and braced together to create a fuel nozzle and injector. Today, that fuel injector is additively printed as one component, simplifying the assembly process, radically improving quality, reducing inventory, and changing the supply chain in fundamental ways. This is an excellent example of AM as a disruptive technology, as it impacts the entire process of part concept, design, manufacture, and assembly, whether that part is injection-molded plastic, cast base metal, or machined superalloy.

The additive process started out very complex, requiring many steps that occurred in a silo mentality, with multiple types of software and individual workstations for design, simulation, print prep, manufacturing, heat treat, and finishing/inspection. Recent advances in digitalization allow a far more cost-effective, end-to-end solution.

It starts with the virtual product – the digital twin – then the virtual production, which is the digital twin production, to the real automation, which is the real machine doing its work. A closed-loop digital chain links all these functions together and keeps them together. It also collects performance data at every step, realizes the data, optimizes it, and has it resident on one collaboration platform with an industrial ring of security. This model provides a great value to the manufacturer by taking real product feedback performance data and feeding it directly back into the original CAD model of the design. By simulating it throughout the entire process for validation, this model can simultaneously predict manufacturing and assembly challenges, adjusting the design as needed to compensate.

3D printing can innovate the way to improve machines, as well. The term RepRap, replicating rapid prototype or robots building robots, is shown in Figure 2.

Figure 3

It shows a print head cooling duct that was designed around computational fluid dynamics (CFD). HP and Siemens collaborated and used digital twin technology on the design and performance, then printed the part on an HP 3D machine. The engineers finally redesigned the part inside the HP machine. This reduced part cost 34%, increased air flow 22%, and resulted in 75% faster part development. The air duct cools down the print heads, keeping them cool during long build times. It had two print heads, and to design this generatively, the part in the center of the slide is fluid in its shape. Today, it would be designed around optimized flow paths for cooling, but this shows how a manufacturer of 3D printers leveraged their printers with AM on the Siemens holistic platform.

Making the move

In the transition from traditional design and manufacturing to additive, in this case powder bed fusion technology, the process begins with these steps, ideally done inside a single software:

Development

  1. Create generative designs, lightweight structures
  2. Validate designs, simulate physical behavior
  3. Adapt, optimize designs
  4. Check part printability

Design

  1. Prepare the part for printing
  2. Predict, compensate for thermal distortion
  3. Plan support structure removal (critical, but often overlooked)
  4. Plan the inspection process

Production

  1. Use full traceability, operator guidance
  2. Improve machine quality, efficiency
  3. Fully automate powder removal
  4. Fully automate support structure removal

Finally, here are five action tips to speed up AM utilization for a company – at the right place, level, and pace.

  1. Understand, ideate – Learn about potentials and threats of AM to your company. To do it, you need to create a vision.
  2. Define, pilot – Identify and design products; if a component is working well, there may not be a reason to 3D print it.
  3. Monetize – It must make money to be accepted.
  4. Scale – Start small, ramp up, and industrialize.
  5. Digitalize – Drive efficiency through digitalization. Simulate the entire process from design through manufacture digitally. Protect knowledge through state-of-the-art data security.

To begin the process, identify a champion at your company who is familiar with your operation and the additive world. Lean on their strength and commitment to improve your company and better position it to remain innovative and competitive in today’s changing marketplace.

Siemens Industry Inc.

About the author: Tim Bell is head of the Additive Manufacturing Center of Competence, Siemens Industry Inc. He can be reached at tim.bell@siemens.com.