The additive manufacturing (AM) industry is expanding rapidly, but residual metal powder remains a significant issue. A collaborative effort between VAC-U-MAX (vacuum conveying systems), GEMCO (blending and drying solutions), and VORTI-SIV (sieving technology) has resulted in the AM-MPRR system for complete metal powder lifecycle management. The new system utilizes advanced vacuum technology to fully extract metal powders from the build box, sieving out foreign debris and oversized agglomerations and reconditioning the on-spec powder for future use.
The AM-MPRR system
The AM-MPRR system addresses key challenges faced by powder bed fusion and binder jet printing operations, offering a comprehensive solution that translates to:
- Reduced waste. By effectively recovering and reconditioning unused metal powder, AM-MPRR minimizes waste and maximizes material utilization.
- Cost savings. Material usage optimization and streamlined operations lead to significant cost reductions in overall printing workflows.
- Improved efficiency. The combined vacuum removal and sieving process significantly reduces downtime, resulting in faster printing cycles.
- Enhanced sustainability. AM-MPRR promotes a more sustainable AM environment by minimizing waste and optimizing material usage.
- Maintained quality. The system ensures that reconditioned powders meet the high-performance standards required for critical AM applications.
The AM-MPRR solution consists of three parts: reclaim, reclassify, and recondition.
Reclaim. The AM-MPRR system utilizes an innovative vacuum conveyor developed by VAC-U-MAX specifically for metal powders, including reactive versions that must be handled in an inert atmosphere. This technology safely and efficiently removes unused metal powder from the build box, eliminating the need for manual handling and reducing the risk of operator exposure and/or explosion. After separating the powder from the airstream, the conveyor then directly deposits the recovered powder onto a sieve to remove oversized materials before conveying the powder once again into the tumble blender for further processing.
Reclassify. A key component of the AM-MPRR system is a vibratory sieve from VORTI-SIV.
This sieve incorporates an ultrasonic anti-blinding device to ensure continuous operation and remove oversized particles and contaminants from the recovered powder. VORTI-SIV's sieving technology plays a crucial role in maintaining consistent reusable powder quality, a critical factor for successful printing through multiple cycles.
Recondition. The recovered and reclassified powder enters GEMCO's tumble blender, which homogenizes the powder into a consistent master batch for reuse in future printing jobs. Flowability can be increased by the use of heat and gas purging. Tests for flowability show the effectiveness of the process.
The GEMCO tumble blender ensures the homogeneity, final chemistry, and flow properties of engineering-grade metal powders for AM printing operations.
Residual identical powder from multiple printers can be delivered to the tumble blender to be homogenized into a consistent master batch for reuse. Another version of the MPRR not only blends the powder effectively but dries it to a single-digit moisture content to improve the powder flowability.
Tumble blenders, with their rotating double-cone or slant-cone vessels, are ideal for mixing metal and alloy powders used in 3D printing. Unlike V-shaped blenders, they can effectively handle these materials’ high bulk densities. The gentle, low-speed tumbling process (1 to 25 rpm) minimizes impact, making the tumble blender suitable for abrasive and fragile powders. Diffusion is the primary mixing mechanism, as the vessel’s rotation on a horizontal axis cascades the powder, exposing fresh surfaces for even distribution.
Proper blending is essential to producing uniformly pure, chemically homogeneous powder within a target particle size distribution that has excellent flow properties and high packing density. One of the main advantages of the double-cone and slant-cone designs is that their geometry allows for complete discharge of the blended material, which translates to high yields, lower risk of contamination, and easy cleaning.
The tumble blenders are designed to operate under vacuum and/or internal pressures that make them suitable for specific requirements such as reduced oxygen concentration. The vessel can also have a jacket for heating or cooling powders during the blending cycle.
Reconditioned powders are stored in all sizes of drums, totes, or bins for storage or immediate re-use.
Additional benefits
The AM-MPRR system offers additional advantages beyond its core functionalities. The system offers an impressive 85% reduction in downtime compared to traditional workflows, significantly boosting overall printing efficiency. It prioritizes safety by being designed for the safe handling of reactive and non-reactive metal powders according to NFPA and UL standards. The AM-MPRR promotes improved ergonomics by eliminating manual powder handling and reducing spillage. Its user-friendly design simplifies maintenance and screen replacement.
This innovative system represents a significant step forward for metal powder management in AM. It offers a compelling solution for AM professionals seeking to optimize their workflows, reduce waste, save costs, and promote a more sustainable future for additive manufacturing.
The AM-MPRR will be unveiled at RAPID + TCT 2024, taking place June 25-27, 2024, at the Los Angeles Convention Center in booths 1525 and 1531.
George Paffendorf is vice president of process engineering & design at GEMCO. David Kennedy is business development manager at VAC-U-MAX. VAC-U-MAX, GEMCO, and VORTI-SIV collectively represent over 230 years of powder handling, processing, and manufacturing expertise, adding technical know-how to the 3D printing industry.
Since 1954, VAC-U-MAX has specialized in the design and manufacture of bulk material handling systems and support equipment used for conveying, weighing, and batching of dry bulk solids.
GEMCO has been providing best-in-class tumble mixing and drying solutions since 1916. A fourth-generation family-owned industrial manufacturer, GEMCO has engineered, produced, and installed thousands of mixers and dryers worldwide and operates the largest tumble mixing and drying technology center.
Since 1968, VORTI-SIV has been a leading manufacturer of the highest-quality sieves, screens, and separation equipment. They service many industries, including food, pharmaceuticals, nutraceuticals, ink, paint and coatings, powder metals, and cosmetics. Their lab, pilot, and production-size equipment are used worldwide for many high-quality wet and dry processes.
GEMCO
www.okgemco.com
VAC-U-MAX
www.vac-u-max.com
VORTI-SIV
www.vorti-siv.com
