Integrating Reliability Centered Maintenance and Spare Parts Stock Control

In the classical approach to determine how many spare parts to stock, the spare parts shortage costs or the minimum fill rate are a key factor. A difficulty with this approach lies in the estimation of these shortage costs or the determination of appropriate minimum fill rates. In an attempt to overcome this problem, we propose to use the data gathered in reliability centered maintenance studies to determine shortage costs. We discuss benefits of this approach. At the same time, the approach gives rise to complications, as the RCM study determines downtime costs of the underlying equipment, which have a complex relation with the shortage cost for spare parts in case multiple pieces of equipment have different downtime costs. A further complication is redundancy in the equipment. We develop a framework that enables the modelling of these more complicated systems. We propose an approximative, analytic method based on the model that can be used to determine minimum stock quantities in case of redundancy and multiple systems. In a quantitative study we show that the method performs well. Moreover, we show that including redundancy information in the stocking decision gives significant cost benefits

Integral optimization of spare parts inventories in systems with redundancies

In this paper, we analyze spare parts supply for a system with a "k-out-of-N" redundancy structure for key components, different standby policies (cold, warm and hot standby redundancy) and local spare parts inventories for sub-components. We assume multiple part types (sub-components) that fail randomly with exponentially distributed interfailure times. Due to the standby policies and the limited number of installed components, the total failure rate depends on the state of the system. Replacement times and stock replenishment times are also assumed to be exponentially distributed and depend on the part types. We present an exact method together with a simple and effi�cient approximation scheme for the evaluation of the system availability given certain stock levels. The proposed approximation is further used in a simple optimization heuristic to demonstrate how the total system costs can be reduced if the redundancy structure is optimized while taking into account the local stock of the spare parts. The presented numerical results clearly show the importance of the local inventories with spares even in the systems with redundancies

Maintenance System of Universal Goss Printing Machine based on failure data using RCM and RCS method

Over time a machine will get experience a decrease in reliability, causing the engine to be damaged at the time of operation, thus disrupting the production line. To maintain a machine remains reliable then a good maintenance system is required. In this research, we will use Reliability Centered Maintenance (RCM) and Reliability Centered Spare (RCS) analysis on the critical system of Goss Universal printing machine based on engine failure data. The result of RCM analysis obtained the optimal preventive maintenance schedule and the type of treatment, while based on the RCS analysis obtained spare part needs following the maintenance schedule. With the result of this analysis, is expected where the machine will keep good and will continue to operate without a sudden breakdown under the production schedule's need. Based on RCM analysis for each critical subsystem obtained interval preventive maintenance for transfer roller 127.60 hours, Ink fountain roller 24.45 hours, ink form roller 29.23 hours respectively, and the wash-up device is no scheduled maintenance. For spare parts inventory strategies the result using RCS method are: transfer roller104 units, ink fountain roller requires 32 units, ink form roller 36 units and are holding spare policy required, and a wash-up device no holding spare parts. Keywords— Failure data, Maintenance System, RCM, RC

TCMS operations and maintenance philosophy

The purpose is to describe the basic philosophies of operating and maintaining the Test, Control, and Monitor System (TCMS) equipment. TCMS is a complex and sophisticated checkout system. Operations and maintenance processes developed to support it will be based upon current experience, but will be focused on the specific needs of TCMS in support of Space Station Freedom Program (SSFP) and related activities. An overview of the operations and maintenance goals and philosophies are presented. The assumptions, roles and responsibilities, concepts and interfaces for operation, on-line maintenance, off-line support, and Operations and Maintenance (O&M) personnel training on all TCMS equipment located at KSC are described

Risk-based stock decisions for projects

In this report we discuss a model that can be used to determine stocking levels using thedata that comes forward from a Shell RCM analysis and the dataavailable in E-SPIR. The model is appropriate to determine stockquantities for parts that are used in redundancy situations, andfor parts that are used in different pieces of equipment withdifferent downtime costs. Estimating the annual production lossusing the model consists of a number of steps. First, we need todetermine which spares are used for the repairs of which failuremodes. In the second step, we estimate the average waiting timefor spares as a function of the number of spares stocked. In thethird step, the annual downtime costs are determined. We combinethe downtime costs with the holding costs to determine the optimalnumber of parts to stock.

Continuous maintenance and the future – Foundations and technological challenges

High value and long life products require continuous maintenance throughout their life cycle to achieve required performance with optimum through-life cost. This paper presents foundations and technologies required to offer the maintenance service. Component and system level degradation science, assessment and modelling along with life cycle ‘big data’ analytics are the two most important knowledge and skill base required for the continuous maintenance. Advanced computing and visualisation technologies will improve efficiency of the maintenance and reduce through-life cost of the product. Future of continuous maintenance within the Industry 4.0 context also identifies the role of IoT, standards and cyber security

Design for availability : creating value for manufacturers and customers

This research introduces a newly developed continuous improvement methodology called Design for Availability that uses principles of Lean Sigma and Design for X to cost-effectively optimize the availability of capital goods, i.e. systems used in the production of other end-products or -services, throughout their entire lifetime. The absence of such a methodology in the literature is remarkable because many users of capital goods increasingly insist on high system availability levels against lower lifetime costs. Against this background this study develops an analytical framework that allows manufacturers to determine the current status of system availability and associated lifetime costs, and to identify opportunities to create additional value for both the manufacturer and its customers. The applicability of this Design for Availability framework is tested through a case study at a global manufacturer of capital goods in the food processing industry. The results show that applying the Design for Availability framework can provide substantial benefits for the manufacturer as well as its customers, as long as a number of critical key success factors are taken into account during implementation, such as organizational commitment to Design for Availability, good leadership and communication, and creating system availability and lifecycle awareness

A review of asset management literature on multi-asset systems

This article gives an overview of the literature on asset management for multi-unit systems with an emphasis on two multi-asset categories: fleet (a system of homogeneous assets) and portfolio (a system of heterogeneous assets). As asset systems become more complicated, researchers have employed different terms to refer to their specific problems. With an objective to facilitate readers in searching conducive studies to their interests, this paper establishes a novel classification scheme for multi-unit systems in accordance with essential features such as diversity of assets and intervention options. Moreover, discerning differences in characteristics between cross-component and cross-asset interactions, we select three types of potential multi-component dependencies (performance, stochastic, and resource) and extend their notions to be applicable to multi-asset systems. The investigation into these dependencies enables the identification of problems that could exist in real industrial settings but are yet to be determined in academia. Ultimately, we delve into modelling approaches adopted by previous researchers. This comprehensive information allows us to offer the insights into the current trends in multi-asset maintenance. We expect that the output of this review paper will not only stress research gaps on multi-asset systems, but more importantly help systematise future studies on this aspect