HyProCell realises automated manufacturing platforms that integrate highly flexible laser-based additive build processes with more conventional yet precise subtractive machining processes. Their combination is referred to as hybrid manufacturing processes.
HyProCell can either build parts additively from scratch and finish them in a single operation or prepare parts by milling and add laser-based additive features achieving otherwise impossible shapes. Apart from producing new parts, existing parts can be repaired or improved by adding new elements.
A conceptual overview of HyProCell (Figure 1) shows how raw materials can be converted into finished products. The part geometries, tool paths and laser scanning patterns are generated by CAx tools. Autonomous and cost effective system operation is achieved by connecting the various machines performing the manufacturing processes over a communication network that runs a manufacturing execution system (MES). The MES both triggers and controls the various manufacturing processes. The manufactured parts are transferred between machines by robotic systems that use specialised clamping systems. Quality inspection is carried out across the different manufacturing phases.
In HyProCell, the above concept and workflow are being validated in industrial pilot facilities by manufacturing parts to meet precise end-users’ requirements. Initially manufactured parts address the aerospace, energy and industrial equipment sectors.
The ultimate goal of HyProCell is to establish how these new types of automated additive manufacturing (AM) cells can enable efficient, flexible and high-throughput production of small lots.
HyProCell incorporates two of the most versatile laser-based additive manufacturing processes, namely Laser Beam Melting (LBM) and Laser Metal Deposition (LMD). The pilot facilities are organised accordingly. All cells benefit from common CAx tools, integration layer and MES.
The LBM pilot cell is installed in the facilities of Poly-Shape (Marseille area, FR) and RAMEM (Madrid, ES). The former covers the entire process chain of additive and subtractive manufacturing with simple (3-axis) post-processing operations, while the latter conducts additional 5-axis post-processing on AM parts. Obviously, in a fully commercial deployment the elements of the cell could be merged into a single cell to reduce transportation costs.
The layout of the production cell at Poly-Shape is depicted in Figure 2.
The Adira Addcreator is the core component of the particular cell. It uses the novel Tiled Laser Melting (TLM) method, which displaces a small chamber over the building area – a key difference from existing LBM processes.
All machines within the cell are equipped with extremely precise repositioning clamping mechanisms (typically found in high precision industrial applications) provided by Erowa, which handle the parts under production.
Following the LBM-based AM process, an Erowa ERD 500 robot transfers the produced part inside an especially designed dustbox to a dedicated cleaning station. At the cleaning station any remaining powder is removed from the part and safely captured, thus diminishing release of powder in the environment.
The part is then transferred by the robot to a 3-axis milling centre in order to bring the part’s surface to the required quality.
The dimensional accuracy of the part is controlled by a measuring machine performing automated 3D scans.
The part handling system is connected to a robotic storage and a loading station for loading new and extracting the finished parts by using a pallet system. The pallets are stored in a rack magazine.
The post-processing cell at RAMEM, which is depicted in (Figure 4) covers primarily polishing, milling and measurement processes. Similarly to the Poly-Shape cell, the machines are connected to a part handling robot system (Erowa ERD 250 XT) that transfers the partly completed LBM-based part (transferred from the Poly-Shape cell) from the loading station to various machines.
For clamping Erowa PCP power chuck is used, while the pallets are in the rack magazine.
Both, a 3+2 milling centre and a 5-axis milling centre are incorporated in the cell. The first is a DMG MORI DMU 50 ECO performing polishing and the second is a Makino D500 performing milling. The machines are located opposite to each other and execute their work flow over their processes automatically using MES. Measurements are carried out manually with a measuring arm (FARO Quantum) in the loading station, and automatically with probes integrated in both machines.
The cell is complemented with a final verification step performed by a coordinate measuring machine (CMM), which is located in a room with controlled temperature. This system measures the geometry of a part by sensing discrete points on its surface with a probe.
The actual implementation of the pilot cell at RAMEM is depicted below.
- LMD Pilot
The LMD pilot is based around the hybrid machine center HSTM 150 HD developed by Hamuel. The machine is located at the Autodesk Technology Centre (Birmingham, UK) and depicted in Figure 6. This combines high-precision and dynamic 5-axes simultaneous machining, LMD, in-process measuring, in-process control devices and adaptive milling.
Notably, the compact laser cladding head is stored in the machine’s tool magazine along with all the other tools and is exchangeable using the tool gripper, like any other available tool. The powder supply system of the machine can simultaneously handle different powders. Switching between powder types, involves cleaning the power supply system.
HyProCell carried out work on developing the integration interface so as to enable the Hamuel hybrid machine to be integrated with the MES, CAx and monitoring modules.
A new mounting device was developed to clamp the bottom (base ring) of the part (nozzle ring) to the hybrid machine. LMD and milling, are used to create blades with connection pins to prepare for joining of a top ring, which is manually attached and welded, again using the machine’s LMD capabilities. A buffer storage capability has been added. A Renishaw laser optical measuring system and a BCT 3D scanning system have been also successfully mounted inside the machine.
Potential extensions include the incorporation of a coordinate measuring machine (CMM) and a fully automated part handling system to form an effective and high-end flexible manufacturing system.