Siavash Haghighat Khajavi

Additive manufacturing in the spare parts supply chain

As additive manufacturing (AM) evolves to become a common method of producing final parts, further study of this computer integrated technology is necessary. The purpose of this research is to evaluate the potential impact of additive manufacturing improvements on the configuration of spare parts supply chains. This goal has been accomplished through scenario modeling of a real-life spare parts supply chain in the aeronautics industry. The spare parts supply chain of the F-18 Super Hornet fighter jet was selected as the case study because the air-cooling ducts of the environmental control system are produced using AM technology. In total, four scenarios are investigated that vary the supply chain configurations and additive manufacturing machine specifications. The reference scenario is based on the spare parts suppliers current practice and the possible future decentralization of production and likely improvements in AM technology. Total operating cost, including downtime cost, is used to compare the scenarios. We found that using current AM technology, centralized production is clearly the preferable supply chain configuration in the case example. However, distributed spare parts production becomes practical as AM machines become less capital intensive, more autonomous and offer shorter production cycles. This investigation provides guidance for the development of additive manufacturing machines and their possible deployment in spare parts supply chains. This study contributes to the emerging literature on AM deployment in supply chains with a real-world case setting and scenario model illustrating the cost trade-offs and critical requirements for technology development.

Challenges to implementing additive manufacturing in globalised production environments

This paper presents the current state of additive manufacturing (AM) implementation in complex supply chains, focusing especially on the globalised consumer electronics industry. A literature review sought to identify bottlenecks to technology transfer, while a qualitative study was carried out using interviews with case company personnel. Finally, an industry survey was used to quantitatively evaluate current production costs and delivery times for AM units. The results highlight the considerable barriers to transferring AM technology to engineering applications. However, there is an untapped potential for manufacturing applications in small-series and pre-series production at the product refinement stages. Furthermore, future projections of AM production throughput and cost reductions will disrupt organisational supply chains. This will lead organisations to create faster design, development and manufacturing cycles, unlocking novel applications and introducing new possibilities to change product architecture at any stage of the product development while compressing the supply chain and allowing for quick responses to changing customer demands.

To kit or not to kit: Analysing the value of model-based kitting for additive manufacturing

Abstract The use of additive manufacturing (AM) for the production of functional parts is increasing. Thus, AM based practices that can reduce supply chain costs gain in importance. We take a forward-looking approach and study how AM can be used more effectively in the production of multi-part products in low to medium quantities. The impact of introducing kitting in AM on supply chain cost is investigated. Kitting approaches are traditionally devised to feed all components belonging to an assembly into individual containers. Where conventional manufacturing approaches are used for kitting, the produced parts pass through inventory and kit preparation steps before being forwarded to the assembly line/station. However, by taking advantage of the object-oriented information handling inherent in the AM process, kitting information can be embedded directly within the digital design data and parts produced in a common build. This model-based kitting practice reduces − even eliminates − the need for a manual kit preparation step and promises additional supply chain benefits. Eight experiments were conducted using laser sintering (LS) to investigate the impact of model-based component kitting on production cost and supply chain cost. The results show that with current state-of-the-art volume packing software, production costs increase with the adoption of kitting. The increased production cost was off-set to different extents by kitting supply chain benefits, including simplified production planning, reduced work-in-progress inventory and elimination of parts fetching prior to assembly. Findings of this research are of interest for manufacturers, service bureaus and practitioners who use AM for low quantity production, as well as developers of AM volume packing and production planning software.

Production Capacity Pooling in Additive Manufacturing, Possibilities and Challenges

Industries such as aviation tend to hold large amounts of capital tied to spare parts inventories to insure a high availability [1]. One effective approach to increase the efficiency in inventory management has been resource pooling [2]. However, the emergence of additive manufacturing (AM) enables the new paradigm of production capacity pooling, which varies from current ones. AM’s inherent characteristics may realize capacity sharing among distinct industries, alleviate the need for high safety stock levels and enable better customer service through the reduction of transshipments for spare parts. The advantages can be extended to the broader fulfillment reach of the firm in other geographical areas without expanding its existing production capacity or inventory (and other benefits from a distributed production setting). However, issues with inter-organizational agreements, testing and production reliability may slow down the pooling process while the required facilities are in place. This paper aims to extend the existing literature on implications of this growing phenomenon on inventory management practices. Study methodology is conceptual analysis.

Manufacturing Digitalization and Its Effects on Production Planning and Control Practices

Advent of additive manufacturing (AM) as a final-parts production method has the capacity to impact the supply chains radically (The Economist, 2012). This effect extends from raw material procurement to production management and further towards distribution and the final customers. Digitalization of production as for the other industries such as automotive and aerospace reduces the operational complexity, while embedding the complexity in the digital components of the system. For instance, the production planning and control for an AM-enabled manufacturing may be distinctly different compared to conventional production methods. Production routing, loading and scheduling can become simplified as steps of production are combined through AM utilization. Moreover, production dispatching, reporting, inspection and corrective actions require development of novel effective practices. In this paper we investigate the in-depth impact of digital production technologies (e.g. additive manufacturing) on the production management practices. Our methodology is based on conceptual modelling intertwined with case data.