Maintenance Operational Costs Research Articles

Energy Management System for Solar-powered Streetlighting Systems

Public lighting or street lighting systems are raised sources of light on the edge of the road or walkway, that is turned ON at night or during bad weather to lighten the streets and turned OFF in the morning. The major problem with streetlights is their excessive energy consumption as most of that energy is wasted because the streets are empty between about 11 pm to 5 am. This also leads to the rapid degration of the streetlights and increased cost of maintenance operations which constitute a financial burden to the municipality. This paper solves this problem by proposing an energy management system for solar-powered streetlights that in addition to turning the streetlights ON when places are dark, puts the streetlights in an energy-saving mode when there is no one on the streets. Vibration sensors are used as motion detectors. The study is focused on the second bridge on the River Wouri, Douala, Cameroon. Simulation of the work is done using Proteus Professional and the results obtained are compared with an estimated daily energy consumption of the existing streetlights on the bridge. It is seen that the energy consumption of the proposed system is 25740Wh, and this is far lesser compared to 187200Wh consumed by the existing system assuming each lamp is 150W.

Workforce training and operations planning for maintenance centres under demand uncertainty

Companies that provide repair & overhaul services to the users of complex technical systems are confronted with uncertain volume of demand when making tactical decisions such as workforce training and planning of repair operations over an annual planning horizon. Given the high importance of equipment availability (e.g. gas turbines) to the users (e.g, power plants), any delay in the delivery of repaired equipment caused by demand uncertainty would lead to significant penalties and loss of customer goodwill. In this paper, a two-stage stochastic programming model is proposed to obtain the optimal number of items to repair, spare part inventory, and the number of operators to train with the goal of minimising the total expected cost of maintenance operations and late delivery. Outsourcing and borrowing strategies are adopted as corrective measures to reduce the probability of late delivery in the emerge of demand uncertainty. Numerical findings illustrate the importance of integrating uncertainty into these operations planning decisions as well as the mitigation strategies in handling the cost of the system.

Multi-component modeling and classification for failure propagation of an offshore wind turbine

PurposeImproving reliability is a key factor in reducing the cost of wind energy, which is strongly influenced by the cost of maintenance operations. In this context, this paper aims to propose a degradation model that describes the phenomenon of fault propagation to apply proactive maintenance that will act on the cause of failure to prevent its reoccurrence as well as to improve future system designs.Design/methodology/approachThe methodology adopted consists in identifying the different components of a wind turbine, their causes and failure modes, and then, classifying these components according to their causes of failure.FindingsThe result is a classification of the different components of a wind turbine according to their failure causes. From the obtained classification, the authors observed that the failure modes for one component are a failure cause for another component, which describes the phenomenon of failure propagation.Originality/valueThe different classifications existing in the literature depend on the nature, position and function of the different components. The classification of this study consists in grouping the components of a wind turbine according to their failure causes to develop a degradation model considering the propagation of failure in the field of wind turbines.

Development of maintenance information systems for landscape and housekeeping components for state green buildings based on state building maintenance guidelines

The problem raised in this study is that the landscape and housekeeping components are damaged so that they do not reach the standard of landscape and housekeeping performance and cannot be used. This has an impact on 4 building interior requirements not being achieved (comfort, safety, health and convenience) and also maintenance operational costs. The problem is caused by the ineffective system of maintaining landscape and housekeeping. The purpose of building maintenance is to make the function, structure, and aesthetics of the building maintained in accordance with the initial conditions. The purpose of this study is to improve maintenance performance landscape and housekeeping components of state’s green building. The research methods used are surveys, literature reviews, and case studies. The result of this study is prove that the maintenance work of green buildings using Minister of Public Works Regulation No. 24/2008-based website can improve maintenance performance landscape and housekeeping components of state’s green building.

Large Format Ceramic Panels Versus Recycled Aluminum Casting Panels: Improvement of the Thermal Behavior of the Museum of Fine Arts of Castellón

There is a growing awareness towards the use in architecture of construction materials produced in the area in which the buildings are to be implemented. The reduction of environmental impacts derived from the lower consumption of energy in transportation is significant. In addition, the materials used in the façades have special relevance in the value of the annual energy demand. This fact becomes more important in the case of emblematic buildings with social media impact, both for the quality of their design and for the functional contributions they can make. Sometimes, even for purely aesthetic reasons, the paradox of opting for constructive solutions with worse performance, worse aging, a higher cost of maintenance operations or a higher value of annual energy demand is established. In this research the Museum of Fine Arts of Castellón is analyzed, made with cast aluminum recycled panels as a finishing material on the façade. A comparison is made with the alternative scenario, ventilated ceramic façade, of having used large format ceramic panels, produced in the region, where the ceramic sector is a very important cluster. The reduction of the value of the annual energy demand by 12% is evaluated by the improvements established in the ventilated ceramic façade.

Digitalization of Oil and Gas Facilities Reduces Cost and Improves Maintenance Operations

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper OTC 27788, “Digitalization of Oil and Gas Facilities Reduces Cost and Improves Maintenance Operations,” by H. Devold, T. Graven, and S.O. Halvorsrød, ABB, prepared for the 2017 Offshore Technology Conference, Houston, 1–4 May. The paper has not been peer reviewed. Copyright 2017 Offshore Technology Conference. Reproduced by permission. The digitalization of oil and gas facilities is becoming a new technical arena. Effective solutions can be used to convert data into information and knowledge, which can then be used to improve maintenance operations. This paper discusses several aspects of this process, ranging from a discussion of maintenance strategies to the opportunities presented by extracting new information from big data. Introduction Fieldbuses, device diagnostics, and advanced management-and-control systems collect large amounts of data, but acquiring and applying methods of exploiting the data have lagged. End users have expressed doubts that they are realizing value from these solutions and have wondered whether a return to simpler systems is needed. In this paper, the authors conclude that condition-based maintenance can reduce the cost of maintenance operations significantly and that further potential in predictive-maintenance regimes exists as experience with base data is gained. Reactive, Scheduled, and Condition-Based Maintenance Strategies A reactive, or break-and-fix, type of maintenance strategy will often present the lowest maintenance operation cost, seen in isolation. But also implied is the cost of production unavailability, the safety risk posed by very hazardous events, and the risk of high repair costs after catastrophic equipment failure. Scheduled or periodic maintenance requires one to estimate failure modes and consequences for all equipment in the plant; then, on the basis of the equipment’s expected lifetime, one calculates inspection intervals and replacement cycles. Because this is often impractical to perform for each individual piece of equipment, equipment is divided into classes depending on type and is given maintenance that is based on that type and its criticality. This approach can have some undesirable effects, including the following: The 80:20 rule may apply; it states that 80% of maintenance intervention is caused by 20% of equipment. A conservative approach that prioritizes avoiding operational failures will lead to short inspection intervals and high maintenance costs. Many sources conclude that human error is the source of as much as 50% of all maintenance issues. Thus, an excessive maintenance intensity will by itself lead to additional failures and the need for even more maintenance.

Condition-based maintenance decision support system for oil and gas pipelines

The 2013 report card of America's infrastructure has scored the condition of oil and gas pipelines as D+ which means that such pipelines are in a relatively poor condition. More than 10,000 failures have been recorded in the US. These failures have resulted in environmental, health and property damages. Therefore, there is a definite need to give more attention to the maintenance of oil and gas pipelines. This paper develops a comprehensive model for the maintenance planning of oil and gas pipelines. The model selects rehabilitation/repair alternatives for oil and gas pipelines based on their condition during their service life. These alternatives are then used to calculate the cash flow throughout the service life of these infrastructures. The model, which uses Monte Carlo simulation and fuzzy approach to address the uncertainties in the estimation of the maintenance operation costs and the economic parameters, calculates the Equivalent Uniform Annual Worth of the identified alternatives. The optimum maintenance programmes consist of the alternatives that have the lowest life cycle cost of oil and gas pipelines. The model is expected to support pipeline operators in the maintenance decision-making process of oil and gas pipelines.

Optimal Design of a Settling Basin for a Small-Scale Drainage Area

This paper develops a nonlinear programming model to optimally design a settling basin for a small-scale drainage area with a minimum total cost. It is assumed that the shape of the settling basin is rectangular parallelepiped, and it is connected to an open channel at both ends. Therefore, the decision variables include the scales of the settling basin (i.e., length, width, and height) and the scales of the channel (i.e., width and height). The design trap efficiency requirement, which must be greater than or equal to the required one of the considered watershed, makes up the main constraint. Other constraints consist of the upper and lower bounds of the decision variables, the equations for computing the trap efficiency, and the average flow velocity in the settling basin. The objective function is to minimize the total annual cost, which is the sum of the land, capital, and maintenance-operation cost. The developed model is solved by using a genetic algorithm. This model is applied to a subwatershed of the Wu-She Reservoir watershed in central Taiwan. The obtained results effectively demonstrate the applicability and practicability of the model.