Influence Of The Quantity Of Parts Per Batch On The Productivity Of Series Production Via Powder Bed Fusion With A Laser Beam of Metals Considering Personnel Shifts

Procedia CIRP, vol. 130, pp. 35–40

Abstract

Powder Bed Fusion with a Laser Beam of Metals (PBF-LB/M) is an Additive Manufacturing technology that allows the production of various complex geometries in one batch. For series production, usually a specific batch is defined and qualified that must not be changed later for qualification reasons. Usually, the geometric maximum of parts per build job is packed for high productivity, leading to high durations per batch of up to several days. A PBF-LB/M machine must be set up manually at the beginning and end of a build job in a comparably short time. Consequently, a 1- or 2-personnel shift system can potentially be used to reduce personnel cost but keep productivity high by carrying out the manual set-up activities for when personnel are present and keeping the machine productive with the long additive build-up during non-shift times. However, it is unclear whether the decision to pack more parts per batch always results in the higher productivity. Manual setup operations could be required during non-shift times, causing unproductive waiting time of the machine until personnel is available again. Technological progress could make it possible in future to change the number of parts without the need for new qualification. However, it remains to be determined if this could increase productivity. This work investigated these open questions based on a simulation of production schedules. In the simulation, scenarios with different assumptions like the number of machines, personnel quantity and shift-systems, and part models are considered. The results show that for series production with identical batches, more parts per batch do not always lead to higher productivity compared to less densely packed batches. Moreover, productivity could be increased by a value that depends on the simulation scenario if the number of parts per build job could be flexibly adapted to the availability of personnel.

Authors 4

1. Lukas Bauch corresponding Aachen

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University Digital Additive Production, Campus Boulevard 73, 52074 Aachen, Germany

2. Jonas Boseila Aachen

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University Digital Additive Production, Campus Boulevard 73, 52074 Aachen, Germany

3. Martin Iza-Mendez Aachen

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University Digital Additive Production, Campus Boulevard 73, 52074 Aachen, Germany

4. Johannes Henrich Schleifenbaum Aachen

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University Digital Additive Production, Campus Boulevard 73, 52074 Aachen, Germany