Spare Parts Supply Research Articles

МАТЕМАТИЧНІ МОДЕЛІ СИСТЕМИ ТЕХНІЧНОГО ОБСЛУГОВУВАННЯ, МОДЕЛІ СТАНІВ У СФЕРІ ОБСЛУГОВУВАННЯ ОЗБРОЄННЯ ТА ВІЙСЬКОВОЇ ТЕХНІКИ

An analysis of the state of the system for the use and restoration of the technical condition of weapons and military equipment (WME) indicates an imperfectly moderate and, accordingly, inefficiently calculated planned restoration using the forces and means of restoring weapons and military equipment. Thus, the imperfectly thought-out system for processing data on the provision of spare parts for equipment is not provided for in a timely manner and is not always accurately and reliably calculated by persons directly responsible for the technical condition of combat vehicles assigned to them. On the basis of operational data, it is necessary to assess the degree of operational readiness of weapons and military equipment when applying the system of maintenance measures recommended in the operating instructions for weapons and military equipment samples. The construction of mathematical models is a preventive measure for carrying out computational processes for the operation of weapons and military equipment and, as a result, understanding the critical points in operation through the consideration of models of weapons and military equipment states in a planned preventive system, the implementation of a qualitative distribution of weapons and military equipment flows by type of state, failure, which accompanies the operation of combat vehicles of training units, which employs personnel practically unfamiliar with the procedure and correctness of safe operation. The study by simulation methods allows you to trace the impact on the frequency of maintenance and the level of operational readiness of the WME sample. Keywords: mathematical model, state models, simulation modeling, flow distribution, failure, maintenance, operation of combat vehicles, technical condition, restoration.

Improving agility and resilience of automotive spares supply chain: The additive manufacturing enabled truck model

The global supply chain disruption by the COVID-19 pandemic is difficult, if not impossible, to estimate as over 94% of the top 1000 fortune companies were badly affected. The need for building resilient supply chains to mitigate the effect of such disruptions is rising rapidly than ever before across the global business spectrum. Building resilience in the automotive spare parts (ASPs) supply chain is critically important as any disruption to automotive spares supply chain will affect the operations of the logistics sector, the backbone of global supply chains. This research work contributes to improving the resilience of the automotive spare parts supply chain by proposing a Viable Supply Chain (VSC) framework design that incorporates Additive Manufacturing (AM) enabled trucks in the automotive spares supply chain network. Based on the proposed model, conceptual case models are developed and tested with proposed AM enabled truck manufacturing closer to end customer. A heuristic approach called shortest time heuristic is also proposed to solve the routing and scheduling of an AM enabled truck to deliver customers’ orders of the spare parts through an online platform. Importantly, the study demonstrate how additive manufacturing can help the ASPs industry to switch from the existing practice of make-to-stock to a more efficient inventory management and cost saving make-to-order model while also achieving resilience and sustainability in by providing a source of spares support for discontinued models of vehicles.

ENTEGRE LOJİSTİK DESTEK SİSTEMİNİN ÖMÜR DEVRİ YÖNETİMİNE ETKİSİ

The Life Cycle is defined as a process that begins with the demonstration of an intended ability and ends when it becomes out of use. Extending the life cycle will reduce costs and increase efficiency.Integrated Logistics Support (ILS); It increases the service life of the products and minimizes the need for support; In this way, it provides financial benefit by reaching higher gains in the long term. Due to the understanding of these benefits, it is a system that is frequently applied by businesses. By successfully applying ILS, the life cycle of aircraft, systems, tools and equipment is extended and costs are reduced.The aim of the study; A product or a system integrated to provide maximum use of the opportunity at minimal cost by extending the life cycle of the Logistics Support Turkey is to identify and remedy the causes of failure of the application.Fieldwork method and interview technique were used in the study. The reasons for the failure of the Integrated Logistics Support application on the life cycle have been identified through a study on aircraft. It has been determined;The positive effect of Integrated Logistics Support especially extends the life cycle, prevents premature modification, prevents price increases in spare parts supply, facilitates the availability of spare parts, facilitates the provision of technical documentation, provides planning and execution of personnel training, and the problems of supplying special tools with the system or vehicle.

Analisis Manajemen Inventory Spare Parts Alat Berat Pelabuhan Model Consignment Stock Guna Meminimumkan Total Inventory Cost (TIC) di PT XYZ

ABSTRACT
 PT. XYZ is a service company engaged in the maintenance of port heavy equipment and modification of port heavy equipment as well as procurement of spare parts for port heavy equipment. In 2018 along with improving the work performance of PT. XYZ expands its wings to civil works in the port sector, starting from dock repair work, maintenance of port accessories, construction of structures and reclamation. In a maintenance service company and the provision of spare parts for port heavy equipment, the company's inventory must be guaranteed. at each site PT. XYZ especially PT. X has a limited warehouse, so it must maximize the company's inventory. In the company's existing condition, the amount of inventory still exceeds the number of user requests which will accidentally fill their warehouse and will increase the Total Inventory Cost (TIC). With this problem, TIC depreciation will be carried out with a periodic review policy (R, s, S) and a periodic review policy with a consignment stock inventory system. Based on the above method, the original TIC amounted to Rp. 43,063,451 with the periodic review method of TIC amounting to Rp. 38,318,736 or decreased by 11% and if using the periodic review method with the inventory consignment stock TIC system, the amount was Rp. 36,987,546 or decreased by 13%.

Information System for Honda Motorcycle Spare Parts Palembang

In practice, the industrial world that looks the same as the service industry requires the players to do a lot of quality improvement in order to compete. Its development is so rapid that many business actors use special tricks to run their business. Likewise with business actors from motorcycle service and service workshops, namely AHASS SPS Motor Palembang. The supply of spare parts that must always be there when customers need them is the main attraction for every workshop. But in reality, there is no special inventory management technique that can help partman to order spare parts in the following month. Therefore, this study will create a web-based spare part inventory information system that can control the amount of spare part stock and help predict the need for spare parts every month with the forecasting technique used, namely the Weighted Moving Average method. The results given from this system are suggestions of spare part stock forecast results with a user-friendly web-based display so that it can improve partman performance, maintain credibility and optimize workshop cashflow

Developing a novel high-strength Al–Mg–Zn–Si alloy for laser powder bed fusion

Additively manufactured (AM) aluminium alloys have attracted increasing attention due to the great demand of prototyping, spare parts supply, short run productions and further light-weighting of vehicles. However, most of the reported AM aluminium alloys are usually modified version of commercial cast or wrought aluminium alloys. In this work, we successfully developed a new high-strength and ductile Al5Mg3Zn2Si alloy, which is designed for laser powder bed fusion (LPBF) process. The optimized relative density of 98.9% was obtained at a volumetric energy density (VED) of 129.1 J/mm3. The as-LPBFed Al5Mg3Zn2Si alloy features refined equiaxed α-Al grains and Al–Mg2Si eutectic network. In addition, the sub-micrometre sized, coherent α-Al(Fe,Mn)Si and MgZn2 dispersoids in conjunction with high number density of (Mg,Zn)-rich GP zones co-contribution to the excellent combination of mechanical properties, i.e. the ultimate tensile strength of 548 MPa, the yield strength of 403 MPa, and the elongation of 6.7%. Such a high-strength and ductile AM aluminium alloys without any addition of costly alloying elements has a great potential for automotive and aerospace applications.

Research on the Comparison between the Different Policies by Service Level and Inventory Level Performance of Auto Parts in N.A.C.C. (North Automobile Components Company)

As after sales services become more and more popular, particularly preventive or corrective maintenance, the intervention and repair of the customer’s goods in a timely and efficient manner ensure customer satisfaction and contribute to the establishment of brand image in the market of the suppliers. The availability and quality of spare parts are key elements of this strategy while ensuring minimal management costs. The reuse of spare parts retrieved from customer systems is a growing maintenance strategy practice which impacts the traditional spare parts supply chain. This reuse is primarily driven by extending the economic life of goods, initially regarded as waste and therefore without added value, by transforming them into valuable spare parts that can be reused; secondly, for environmental or regulatory reasons, demanding responsibility for the treatment of products at the end of their life; and thirdly, to improve the availability of parts for maintenance, especially parts that the organization can no longer purchase or that are impacted by other issues. It also involves the analysis of their condition and their eventual return to working order as they are retrieved from the customer’s systems in a defective condition. In this paper, we will identify and classify the different customers and spare parts by estimating the critical level of rationing policy based on forecasts, identify the thresholds of inventory management policies, and finally, compare the different policies by service level and inventory level performance for the N.A.C.C. company.

Distributed 3D Printing of Spare Parts via IP Licensing

Problem definition: We consider an OEM supplying a single part to multiple buyers over an infinite horizon. We study how the OEM can digitize the spare parts supply chain by leveraging 3D printing via intellectual property (IP) licensing. Academic/practical relevance: Additive manufacturing, also known as 3D printing, has the potential to shift supply chains from global networks that rely on centralized production with traditional manufacturing technologies to mainly digital networks with distributed, local printing. Particularly well positioned to drive this transition are original equipment manufacturers (OEMs) who design and produce capital goods. Methodology: We first set up a benchmark model of the traditional physical supply chain with centralized production by the OEM. We then propose the OEM to act as an IP licensor by selling spare parts designs, rather than physical parts. With the license agreement, a buyer can print parts locally through a third-party printing service provider, enjoying a shorter lead time and lower setup cost. Given a license, each buyer chooses whether to switch to the IP licensing channel or stay in the traditional channel. The OEM selects the license terms to maximize the total profit across both channels. Results: We characterize the OEM’s optimal license and the resulting supply chain configuration. We show that 3D printing’s competency in price plays a dominant role in production decentral- ization. The conventional wisdom that 3D printing is suitable for slow moving parts holds only when it is competent along several dimensions. In a numerical experiment with realistic parameter settings, decentralized production occurs in a surprisingly large number of cases, and the proposed new business model can significantly increase the OEM’s profit. Managerial implications: Our results indicate that IP licensing by OEMs can become a major enabler in the transition to digital supply networks with distributed 3D printing, benefiting all parties involved.

Assessment of Spare Parts Requirement by Reliability: A Case Study

Spare parts provision is a complex problem and requires an accurate model to analyze all factors that may affect the required number of spare parts. The number of spare parts required for an item can be effectively estimated based on its reliability. The reliability characteristics of an item are influenced by different factors such as the operational environment, maintenance policy, operator skill, etc. However, in most reliability-based spare parts provision (RSPP) studies, the effect of these influence factors has not been considered. Hence, the statistical approach selected for reliability performance analysis must be able to handle the effect of these factors. One of the important models for reliability analysis by considering risk factors is the proportional hazard model (PHM), which has received less attention in the field of spare parts provisioning. Thus, this paper aims to demonstrate the application of the available reliability models with covariates in the field of spare part predictions using a case study. The proposed approach was evaluated with data from the system of fleet loading of the Jajarm Bauxite mine in Iran. The outputs represent a significant difference in spare parts forecasting and inventory management when considering covariates.

Hypergraph-based joint optimization of spare part provision and maintenance scheduling for serial-parallel multi-station manufacturing systems

This paper studies the joint modeling of spare part provision and maintenance scheduling for Serial-Parallel Multi-station Manufacturing Systems (SPMMS), where the spare part connections are especially investigated. In the SPMMS, multiple types of spare parts are retained for uncertain failures of the stations, and multiple stations may share the spare parts in inventory. To describe the spare part connections among the stations, a hypergraph-based model is introduced. In the system-level maintenance, the SPMMS is formulated to be a multi-connection hypergraph, with the Spare Part Hyperedges (SPH), the cost-saving hyperedges and the capacity-loss hyperedge involved. Based on the multi-connection hypergraph, a Combination-Spread Opportunistic Maintenance (CSOM) policy is proposed. To obtain the optimal alternatives of the maximum inventory levels, the length of the combination window and the length of the spread window, a hierarchical optimization method is developed. The case study and the comparisons show that the proposed hypergraph-based CSOM policy is more cost-effective than the traditional maintenance policy, the station-level maintenance policy and the fixed-group maintenance policy. Finally, the discussion shows that the traditional maintenance model is a special scenario of the hypergraph-based model.

Spare Parts Transportation Optimization Considering Supportability Based on Uncertainty Theory

Ensuring a consistent, continuous, and efficient spare parts supply is a critical issue that must be addressed in the equipment support system. In order to effectively improve the coverage level and handle the common asymmetry information present in practical applications, the spare parts transport vehicle routing and scheduling model was further optimized. We integrated supportability requirements and uncertainty theory into the model to better describe the actual uncertain demand of each site. We selected three critical supportability indicators as constraints, redefined them with uncertain variables, and then completed the chance-constrained model on this basis. Once the confidence level is specified, the uncertain constraints can be transformed into deterministic constraints, and finally, the equivalent deterministic model can be solved easily. In addition, a feasible solution can be found through a genetic algorithm, and a numerical example is provided to validate the model’s rationality. The proposed method successfully seeks the balance between the total cost and supportability.

Maintenance of rural water supply facilities in the Builsa North District of the Upper East Region of Ghana

In Ghana, the sustainability of rural water supply facilities has been a recurring national issue. Therefore, this study examined the maintenance structures, as they exist for the effective management of water supply facilities in the Builsa North District. The study was descriptive, non-interventional and applied the mixed method approach to collect data from 138 water users who were randomly selected from hand pump communities. The study found that the management architecture of the water supply systems of the district hinged on the District Water and Sanitation Teams (DWSTs), Water and Sanitation (WATSAN) committees, area mechanics and pumped spare-parts dealers. The significant constraints to pump maintenance were inadequate logistics, finance, and remuneration of DWST, poor financial mobilisation, financial embezzlement, and high attrition among WATSAN committee members. Additionally, poor transport support for area mechanics, bad access routes, and scarcity of spare parts were also significant constraints to the maintenance architecture. The study recommends government and donor/agency to provide requisite financial and logistical support to the DWSTs, WATSAN committees and area mechanics and provision of spare parts at affordable prices.

Online joint replacement-order optimization driven by a nonlinear ensemble remaining useful life prediction method

Remaining useful life (RUL) prediction and maintenance optimization are two critical and sequentially connected modules in the prognostics and health management of machines. Due to the advantages of obtaining more accurate RUL prediction results and the effectiveness of addressing replacement scheduling and spare parts provision dynamically, ensemble RUL prediction and online joint replacement-order optimization are paid specific attention to. Despite substantial works on those two aspects, there are still two limitations that compromise their performances in practical applications: 1) Existing ensemble RUL prediction methods neglected the nonlinear relationships among individual prediction models. 2) No online joint optimization model that utilizes ensemble RUL information is available. Faced with these two limitations, this paper first proposes a nonlinear ensemble RUL prediction method, which takes nonlinear relationships among models into consideration. Furthermore, an online joint replacement-order model is formulated using the ensemble RUL prediction results, and an iterated local search-based optimization algorithm is utilized for dynamically finding the near-optimal joint policies. Through the experimental study of milling cutter life tests, the proposed nonlinear ensemble RUL prediction method is verified with higher accuracy, and the joint optimization model utilizing the ensemble RUL results is shown to provide more effective joint policies.

Sistem Pendukung Keputusan Pemilihan Vendor Project Menerapkan Metode Analytical Hierarchy Process (AHP)

Procurement of goods and services is one of the initial stages in the procurement of a project, including the selection of project vendors. Some of the problems that exist when working on a project such as delays in the provision of spare parts and incompetent experts in project work greatly affect the smooth running of the project. The right vendor selection is one of the keys to the company's success in completing a project. The Analytical Hierarchy Process (AHP) method is a method that can help companies make decisions, especially in the selection of project vendors. From the results of calculations using the Analytical Hierarchy Process (AHP) method for the selection of project vendors based on the main criteria, the most important in selecting project vendors is quality with a weight of 0.36, Vendor B is in first place with a weight of 0.35 or equal to 33.1%, vendor A is in the second position at 0.30 or 27.4%, vendor D is in the third position at 0.18 or 21.4%, the last position is occupied by vendor C at 0.17 or 18.1%

A decision support system for configuring spare parts supply chains considering different manufacturing technologies

A well-configured spare parts supply chain (SC) can reduce costs and increase the competitiveness of spare parts retailers. A structured method for configuring spare parts SCs should be used to determine whether to centralise or decentralise inventory management, also considering hybrid configurations. Moreover, such a method should define whether or not to switch the production of spare parts from Conventional Manufacturing (CM) technologies to Additive Manufacturing (AM) ones. Indeed, AM is considered the next revolution in the field of spare parts, and the adoption of AM technologies strongly affects the characteristics of SCs. However, the choice between centralisation and decentralisation is not the subject of much scientific research, and it is also not clear when AM would be the preferable manufacturing technology for spare parts. This paper aims to assist managers and practitioners in determining how to design their spare parts SCs, thus defining both the spare parts SC configuration and the manufacturing technology to adopt through the development of a decision support system (DSS). The proposed DSS is a user-friendly decision tree, and, for the first time, it allows comparison of the total costs of SCs characterised by different degrees of centralisation with both AM and CM spare parts.

ВИКОРИСТАННЯ ОПЕРАТОРНОЇ МОДЕЛІ ПРОЦЕСУ ЕКСПЛУАТАЦІЇ ОЗБРОЄННЯ ТА ВІЙСЬКОВОЇ ТЕХНІКИ ДЛЯ ФОРМУВАННЯ ПОТОКІВ ОБСЛУГОВУВАННЯ ТА ВІДНОВЛЕННЯ У СИСТЕМАХ ПІДТРИМКИ ПРИЙНЯТТЯ РІШЕНЬ ПОСАДОВИХ ОСІБ ЛОГІСТИКИ

The analysis of the organization of training of personnel on equipment indicates the imperfection of calculations of the needs of equipment to achieve the qualitative goal of training, respectively, the ineffective use of forces and means. There are systemic omissions in the background of the organization of the technical condition recovery system, high-quality planning and forecasting of the main failures of the technical condition, thereby an imperfectly thought-out data processing system for the provision of spare parts for equipment, information about which should be available on the interfaces of computer workstations of logistics officials for carrying out routine repairs to replenish resource reserves in order to carry out timely maintenance of equipment by the forces of full-time drivers in accordance with their functional duties. It is the principle of prevention that is the most important criterion in building a system, which can be depicted using the method of typical operators through an operator model for planning activities involving military equipment for training personnel in training support units and makes it possible to calculate the preliminary required amount of equipment using a mathematical model, with the condition for understanding the declared as necessary in terms of quantity for the high-quality implementation of the planned event without disruptions, and provides an approximate situational vision, namely, distribution of flows of weapons and military equipment by type of state, failures, accompanied by the operation of combat vehicles by personnel who are practically not familiar with the order of the equipment attached to it. Keywords: distribution of flows of weapons and military equipment by type of state, failures, maintenance, operation of combat vehicles, technical condition, restoration, operator model, mathematical model, method of typical operators, data processing, background, interface of computer workstation.

Operational planning in service control towers – heuristics and case study

We study performance improvement in multi-echelon, closed loop spare part supply chains using operational interventions based on real-time status information. Our objective is to minimize the total cost relevant costs, consisting of intervention costs and the backorder costs. In this paper, we focus on proactive interventions, aiming to avoid stockouts. We assume that all reactive interventions are fixed. Proactive interventions that we study include lateral transshipments, emergency shipments, stock reservations, expediting part repairs, and early new buys of parts. These interventions are invoked by using alert generation, when the supply chain status deviates from the plan. We propose heuristic rules to generate alerts. We also develop heuristic rules for the choice of operational interventions. We model and test our heuristics in a simulation test bed, based on data of a global IT company by using the case data in Germany. Numerical experiments reveal the following key insights: (i) downstream interventions – proactive lateral and emergency shipments – have most impact in reducing costs, (ii) communicating losses in the supply chain (no returns, failed repairs) for early new buys has positive impact on fill rates at negligible costs, and (iii) expedite repair and stock reservations using the proposed rules is not profitable.

A comprehensive literature review on spare parts logistics management in the maritime industry

Supply chain and logistics management for spare parts is of key importance in the maritime industry, in order to ensure high availability and reliability of assets, while keeping operating costs in acceptable levels. Supply chain and logistics operations for spare parts incorporate high complexity, uncertainty and costs, due to special characteristics of the maritime sector, as for instance moving assets, globally scattered points of supply and demand, strict time windows and multi-actor setting. Typically, the asset owner purchases spare parts for their vessel from a foreign supplier, and consolidates them in a regional warehouse. Subsequently, these spare parts are shipped to a port using various means of transport such as air freight, sea freight or road freight. Finally, once the vessel calls at subject port, the spare parts are delivered and used on board for maintenance activities. For repairable items, the reverse logistics process also does exist; a spare part is offloaded from a vessel, repaired and then re-delivered on board. Efficiently handling such a logistics network constitutes a great challenge, nevertheless, this topic has received little attention in the literature and a systematic review is currently missing. In this paper, the authors attempt to address this research gap by performing a systematic literature review on spare parts supply chain and logistics management in the maritime sector. To achieve this objective, after applying the defined inclusion and exclusion criteria on the initial search results, a set of (30) eligible papers, participating in the review, has been identified. These selected papers are illustrated and discussed in detail, with the purpose of addressing the research questions initially set by the authors. Fundamentally, this study aims to describe the current state of the art in the subject area, identify existing challenges and trends, and finally provide suggestions on future research. We aspire that the results of this review can be used as the foundation for future research on spare parts supply chain management in the maritime sector.

Multi-level Framework for the Assessment of Additive Manufacturing for Spare Parts Supply

The main objective of spare parts supply is to maximize the service level whilst minimizing costs of tied-up capital, operational activities and administrative processes. Additive Manufacturing (AM) offers the opportunity to decentralize the supply chain and manufacture on-demand without minimum order quantities. While AM could improve sustainability, it also could lead to less eco-efficient localized production or problem shifting within the value chain. To enable a holistic decision support for the changeover to AM, a multi-level framework for the interdisciplinary assessment of AM in spare parts supply is developed and enhanced by an agent-based modelling approach for quantitative assessment.

Machine learning approach for integrated maintenance and spare parts management strategies

We targeted a data mining and machine learning approach for integrated maintenance/production and spare parts management problems for components of a wind farm where the level of degradation is noticeable. The degradation is established as a function of the actual functioning mode. Spare parts are stored in a local inventory. The costs associated with the supply of spare parts and their renewal are related to the functioning mode. Our goal is to use a data mining and a machine learning approach in order to optimize the total current cost of maintenance, production and spare parts related costs over a fixed planning horizon. We formulate the problem of the optimal policy structure, which turns out to be a three-threshold policy in all operating modes. Our numerical results show that the cost reductions achieved by the integrated maintenance, production and spare parts optimization are significant.