유지관리 모니터링을 통한 국가어항 방재시스템의 유지관리수준에 관한 연구

조영진,김영서 (사)한국연안방재학회 2019 한국연안방재학회지 Vol.6 No.2

The breakwater of the national fishery port is currently under going rapid aging and the possibility of destruction due to climate change is increasing and maintenance costs are expected to rise sharply. Therefore, it is necessary to reduce the cost of LCC by securing the safety of the national fishery port breakwater and long life. Based on this recognition, this study defines the maintenance level of the national fishery port breakwater and suggests appropriate maintenance level for rational decision making of maintenance. The appropriate maintenance level of national fishery port breakwater is as follows: 1. The maintenance according to service life of facilities is current maintenance level, 2. The maintenance according to breakwater damage rate is Current maintenance level or preventive maintenance level, 3. The maintenance according to change in design wave is preventive maintenance level.

An Introductory Study on ImPerfect Maintenance Effect in Rolling Stocks

Jong Woon Kim,Seok Yun Han,Jong Duk Chung 한국철도학회 2008 International Journal of Railway Vol.1 No.2

The maintenance effect is a peculiar factor applied to repairable systems such as rolling stocks. Conventional statistical analysis for failure times takes into account one of the two following extreme assumptions, namely, the state of the system after maintenance is either as "good as new" (GAN, perfect maintenance model) or as "bad as old" (BAO, minimal maintenance model). Most of the papers concerning the stochastic behavior of railroad systems assume two types of maintenance: perfect and minimal maintenance. However, Lee, Kim & Lee (2008) analyzed the failure data of a door system in Metro EMU and the effect of preventive maintenance was imperfect. It is seen that the imperfect maintenance is of great significance in practice. This article describes how to deal with the maintenance effect in reliability studies of rolling stocks. Maintenance policies under imperfect maintenance are described and the method is proposed to evaluate their performance.

세계적수준의 설비관리 프레임워크 개발

구성태 대한산업공학회 2020 대한산업공학회지 Vol.46 No.3

The purpose of this study is to develop a world class maintenance framework for manufacturing innovation and safe operation of critical facilities. The new world class maintenance framework was developed by analyzing the world class maintenance framework presented in previous studies and evaluating the commonality of maintenance elements, the relevance of maintenance departments, and the expertise of maintenance work. The study presented four maintenance subsystems, one support tool, and 18 implementation elements for world class maintenance. The proposed framework reflects the characteristics of maintenance processes and maintenance tasks such as maintenance strategies, input elements, maintenance systems, and output elements, which are not presented in previous studies. The proposed framework is meaningful in that it presents a clear implementation elements and directions for innovation of maintenance to companies or researchers who want to improve maintenance to a global level.

야전운용제원과 신뢰도중심정비에 기반한 장갑차 암내장형 유기압 현수장치(ISU) 정비계획 최적화

이현석,이두열 한국신뢰성학회 2024 신뢰성응용연구 Vol.24 No.1

Purpose: This study utilizes reliability-centered maintenance (RCM) to analyze the in-armed suspension unit (ISU) of armored vehicles. The aim is to propose a maintenance schedule that minimizes maintenance costs based on the RCM analysis. Methods: Fault tree analysis was performed to define the failure modes of the armored vehicle ISU system. The life distribution parameters for each part of the ISU were estimated using field operation data. Subsequently, the probability of failure and the number of expected failure events of a reference group comprising 100 armored vehicles were calculated by considering operation time. Lastly, a parametric study was conducted to determine the optimal maintenance schedule. Results: This study utilizes RCM to present the root cause of ISU failure and its consequences. Considering the targeted operational time, the optimal maintenance schedule was 90 h of operation for 100 armored vehicles. Performing maintenance at this interval resulted in the lowest maintenance costs. Conclusion: Introducing maintenance after every 90 h of operation instead of the current corrective maintenance scheme is expected to reduce the frequency of unexpected failures and minimize the costs associated with unscheduled maintenance. This method can be applied to other equipment subject to gradual deterioration to determine the optimal maintenance schedule.

원자력발전소 가동중정비 대상계통 및 기기 선정 방법론 개발

이영주,조경수,김재성 한국에너지학회 2023 에너지공학 Vol.32 No.3

Overseas nuclear power plants such as the U.S. have been actively implementing maintenance during operation by utilizing risk information since the late 1990s, whereas domestic nuclear power plants have specified that they cannot intentionally enter limited condition of operation for preventive maintenance in their technical specifications. However, discussions on implementation of on-line maintenance using risk information have recently restarted in Korea Hydro & Nuclear Power(KHNP). In this paper, the target systems & components selection methodology and application results for on-line maintenance using the currently operating preventive maintenance program were presented. The systems included in the level 1 Probabilistic Safety Assessment (PSA) evaluation and systems evaluated as functions of high safety significance in the MR (Maintenance Rule) were selected as target systems for on-line maintenance. As a target components selection method, the Functional Equipment Group (FEG) was used for the target system for on-line maintenance. To estabish the functional equipment group, a representative component for each system was selected from the point of view of on-line maintenance, and then, based on this, the maximum range of components that functionally do not affect other systems were considered, and additionally, components that support the functions of this representative component were also included. In addition, it was possible to evaluate the time required for each maintenance work and work details by linking the maintenance items developed as the corresponding maintenance work items in each functional equipment group. Lastly, for the maintenance work of the selected equipment, a work evaluation procedure was prepared in terms of maintenance risk, power plant shutdown, and industrial safety to facilitate the composition of the work package. As a result of applying this methodology to Saeul 1, an APR1400 nuclear power plant, 39 systems out of a total of 153 systems were selected as target systems, and a total of 447 functional equipment groups were developed for 31 systems, excluding 8 power-related systems. In addition, the maximum maintenance duration time of each functional equipment group was evaluated so that it could be used as out of service time, which is essential for maintenance risk evaluation and work management plan establishment.

사출성형 공정에서의 통합정비방법에 관한 연구

박철순(Chulsoon Park),문덕희(Dug Hee Moon),성홍석(Hongsuk Sung),송준엽(Junyeop Song),정종윤(Jongyun Jung) 한국산업경영시스템학회 2015 한국산업경영시스템학회지 Vol.38 No.3

Recently as the manufacturers want competitiveness in dynamically changing environment, they are trying a lot of efforts to be efficient with their production systems, which may be achieved by diminishing unplanned operation stops. The operation stops and maintenance cost are known to be significantly decreased by adopting proper maintenance strategy. Therefore, the manufacturers were more getting interested in scheduling of exact maintenance scheduling to keep smooth operation and prevent unexpected stops. In this paper, we proposedan integrated maintenance approach in injection molding manufacturing line. It consists of predictive and preventive maintenance approach. The predictive maintenance uses the statistical process control technique with the real-time data and the preventive maintenance is based on the checking period of machine components or equipment. For the predictive maintenance approach, firstly, we identified components or equipment that are required maintenance, and then machine parameters that are related with the identified components or equipment. Second, we performed regression analysis to select the machine parameters that affect the quality of the manufactured products and are significant to the quality of the products. By this analysis, we can exclude the insignificant parameters from monitoring parameters and focus on the significant parameters. Third, we developed the statistical prediction models for the selected machine parameters. Current models include regression,exponential smoothing and so on. We used these models to decide abnormal patternand to schedule maintenance. Finally, for other components or equipment which is not covered by predictive approach, we adoptedpreventive maintenance approach. To show feasibility we developed an integrated maintenance support system in LabView Watchdog Agent and SQL Server environment and validated our proposed methodology with experimental data.

발전설비용 회전기계의 소급적 신뢰도중심정비 사례 연구

김희수(Heesoo Kim),노영진(Youngjin Roh),손정욱(Jungwook Son),임강민(Gangmin Lim),김선화(Seonhwa Kim) 대한기계학회 2021 대한기계학회 논문집. Transactions of the KSME. C, 산업기술과 혁신 Vol.9 No.1

본 논문에서는 소급적 신뢰도중심정비의 방법론을 회전기기의 정비 이력 데이터를 통하여 최적의 정비 주기를 도출한 사례를 소개하였다. 소급적 신뢰도중심정비는 대상 설비의 정비 현황을 분석하고, 설비의 신뢰도를 향상시키기 위하여 고장 라이브러리의 FMEA 결과를 기반으로 누락된 정비를 차기 정비전략에 적용하는 분석 방법이다. 본 연구에서 사례 연구로 활용한 데이터의 대상 설비는 펌프, 팬, 모터이며 사용된 정비 이력은 계획예방정비 정보이다. 사례 연구를 통하여 대상 설비에 대한 MTBF, MTTR, MTTI 의 핵심 지표가 도출되었으며, 이 지표는 정비 전략의 정비 주기를 결정하는 의사결정 알고리즘 변수로 활용되었다. 발전설비의 보수적인 예방정비로 인하여 고장 데이터의 확보가 어려우므로 본 연구에서는 선택적 의사 결정 알고리즘 적용이라는 개념을 도입하여 데이터를 분석하였다. 의사결정 알고리즘은 가용도 기준, 정비 시간 기준, 총 정비 비용 기준 알고리즘으로 구성되어 있으며, 대상 설비의 정비 이력에 따라 최적의 알고리즘을 적용하여 데이터 분석하였다. 또한 각각의 알고리즘은 Weibull Analysis 를 통한 주요 변수를 산출한 후 최적의 정비 주기 또는 검사 주기를 도출하였다. In this paper, we introduced a case of deriving an optimal maintenance cycle through retrospective reliability-based maintenance methodology through maintenance history data of rotating equipment. Hybrid reliability centered maintenance is an analysis method that analyzes the maintenance status of the target equipment and applies the missing maintenance to the next maintenance strategy based on the FMEA results of the failure library to improve the reliability of the equipment. The target machinery of the data used as a case study in this study are pumps, fans and motors, and the maintenance history used is information on planned preventive maintenance. Through the case study, the key indicators of MTBF, MTTR, and MTTI for the target equipment were derived, and this indicator was used as a decision algorithm variable to determine the maintenance cycle of the maintenance strategy. Because it is difficult to secure fault data due to the conservative preventive maintenance of machinery in power generation, this study analyzed the data by introducing the concept of applying an optional decision algorithm. The decision-making algorithm is composed of 3 algorithms (the availability, maintenance time and total maintenance cost). Data is analyzed by applying the optimal algorithm according to the maintenance history of the target machinery. In addition, each algorithm calculated the main variables through Weibull Analysis and then derived the optimal maintenance or inspection cycle.

BIM 기반 건축물 스마트 유지관리 지원 COBie 문서 프로토타입

구교진,박상헌,조동현 한국산학기술학회 2019 한국산학기술학회논문지 Vol.20 No.12

효과적인 시설물 유지관리를 위해서는 유지보수공사 이력정보, 자재정보 등 다양한 유지관리 정보의 수집과 관리가 요구된다. 대형화, 복잡화 추세인 건축물들의 많아진 유지관리 업무량 해소를 위한 정보관리기술 및 시스템들의 도입에도 불구하고 유지관리정보들이 제대로 활용되지 않고 있다. 대안으로 BIM의 도입 및 활용 연구가 지속적으로 수행되고 있지만 설계단계에서 생성된 BIM 모델의 건축 유지관리 정보 미비로 인하여 실무에서 활용되지 못하고 있다. 본 연구는 건축물 관리자가 수행하는 BIM 기반의 스마트 유지관리 업무를 지원하기 위한 COBie 문서 프로토타입을 제안하였다. 다양한 유형의 유지관리 프로젝트 업무절차를 정형화하기 위해 BIM 기반 유지관리 기본 프로세스 모델을 점검업무와 유지보수업무로 구분하여 제시하고 단계별 유지관리 필요정보를 도출하였다. 설계단계에서 생성된 BIM 모델의 속성정보들 중 기본 프로세스 단계별 유지관리 필요정보에 해당하는 파라미터들을 도출하였으며, 이를 바탕으로 7개 스프레드시트로 구성된 COBie 문서 프로토타입을 제안하였다. 사례적용을 통해 유지관리 정보가 미포함된 KBIMS 라이브러리 기반의 설계단계 BIM 모델을 유지관리 단계에서 활용 가능한 것으로 확인하였다. For effective building maintenance, the collection and management of various maintenance date such as work history information and material information is required. Despite the introduction of information management technologies and systems to reduce the amount of maintenance work of buildings, which have become larger and more complex, the maintenance information is not being utilized properly. As an alternative, research on the introduction and utilization of BIM is being conducted continuously. However, the BIM models generated at the design phase are not utilized in practice due to a lack of architectural maintenance information. This study proposed a COBie document prototype to support BIM-based smart maintenance tasks performed by building managers. In order to formalize various types of maintenance work procedures, a BIM-based maintenance process model is presented in two categories: inspection and maintenance. Among the BIM attribute data of the BIM model generated at the design phase, the parameters corresponding to the maintenance necessary information for each basic process are derived. Based on this, we proposed a COBie document prototype consisting of seven spreadsheets. The results of a case study confirmed that the KBIMS library-based BIM model created at the design phase without the maintenance information can be used at the maintenance phase.

발전설비용 회전기계의 소급적 신뢰도중심정비 사례 연구

김희수,노영진,손정욱,임강민,김선화 대한기계학회 2021 기술과 교육 Vol.9 No.1

본 논문에서는 소급적 신뢰도중심정비의 방법론을 회전기기의 정비 이력 데이터를 통하여 최적의 정비 주기를 도출한 사례를 소개하였다. 소급적 신뢰도중심정비는 대상 설비의 정비 현황을 분석하고, 설비의 신뢰도를 향상시키기 위하여 고장 라이브러리의 FMEA 결과를 기반으로 누락된 정비를 차기 정비 전략에 적용하는 분석 방법이다. 본 연구에서 사례 연구로 활용한 데이터의 대상 설비는 펌프, 팬, 모터이며 사용된 정비 이력은 계획예방정비 정보이다. 사례 연구를 통하여 대상 설비에 대한 MTBF, MTTR, MTTI 의 핵심 지표가 도출되었으며, 이 지표는 정비 전략의 정비 주기를 결정하는 의사결정 알고리즘 변수로 활용되었다. 발전설비의 보수적인 예방정비로 인하여 고장 데이터의 확보가 어려우므로 본 연구 에서는 선택적 의사 결정 알고리즘 적용이라는 개념을 도입하여 데이터를 분석하였다. 의사결정 알고리 즘은 가용도 기준, 정비 시간 기준, 총 정비 비용 기준 알고리즘으로 구성되어 있으며, 대상 설비의 정비 이력에 따라 최적의 알고리즘을 적용하여 데이터 분석하였다. 또한 각각의 알고리즘은 Weibull Analysis 를 통한 주요 변수를 산출한 후 최적의 정비 주기 또는 검사 주기를 도출하였다. In this paper, we introduced a case of deriving an optimal maintenance cycle through retrospective reliability-based maintenance methodology through maintenance history data of rotating equipment. Hybrid reliability centered maintenance is an analysis method that analyzes the maintenance status of the target equipment and applies the missing maintenance to the next maintenance strategy based on the FMEA results of the failure library to improve the reliability of the equipment. The target machinery of the data used as a case study in this study are pumps, fans and motors, and the maintenance history used is information on planned preventive maintenance. Through the case study, the key indicators of MTBF, MTTR, and MTTI for the target equipment were derived, and this indicator was used as a decision algorithm variable to determine the maintenance cycle of the maintenance strategy. Because it is difficult to secure fault data due to the conservative preventive maintenance of machinery in power generation, this study analyzed the data by introducing the concept of applying an optional decision algorithm. The decision-making algorithm is composed of 3 algorithms (the availability, maintenance time and total maintenance cost). Data is analyzed by applying the optimal algorithm according to the maintenance history of the target machinery. In addition, each algorithm calculated the main variables through Weibull Analysis and then derived the optimal maintenance or inspection cycle.

DACUM 기반 전기정비직 종사자의 직무분석 및 교육요구분석 - H사 전기정비직 종사자 중심으로 -

서경원,배광민,윤관식 한국직업교육학회 2017 職業 敎育 硏究 Vol.36 No.6

본 연구의 목적은 H사에 재직 중인 생산에 직・간접적으로 관여하고 있는 전기정비직 종사자를 대상으로 직무를 분석하여 책무와 작업을 도출하고, 작업을 수행하기 위해 필요한 지식/기술/태도/도구를 도출하며, 설문조사를 통한 교육요구분석에서 우선순위를 파악하는 것이다. 연구문제 해결을 위하여 DACUM 직무분석을 통해 직무를 규명하고 4개의 책무와 33개의 작업을 도출하여, 설문조사를 실시하였다. 이후, 작업에 대한 검증을 진행하였고 교육요구분석을 수행하였다. 연구는 H사 전기정비직 종사자를 대상으로 실시하였으며, DACUM 직무분석을 위한 위원회에는 퍼실리테이터 1명과 코디네이터 1명, 전기정비직에 종사하는 최소 19년 이상의 경력을 가진 내용전문가 7명이 참여하였다. 이후 DACUM 직무분석을 통해 도출된 결과를 검증하기 위해 현업부서 관리직 전문가 5명이 참여하였다. 설문조사는 전기정비직에 종사하는 전체 342명을 대상으로 실시하였으며, 총 342부중 256부를 회수하였으나 최종분석에는 222부가 활용되었다. 연구결과 첫째, 전기정비직 종사자의 직무는 ‘수배전 유지보수’, ‘자동제어 유지 보수’, ‘전기기기 유지보수’, ‘계측장비활용 유지보수’ 의 4개 책무와 33개의 작업으로 구성되어 있음을 확인하였다. 둘째, 도출된 33개의 작업을 수행하기 위해 필요한 지식/기술/태도/도구를 도출하였다. 셋째, 설문결과 전기정비직 종사자 작업의 우선순위를 규명하기 위하여 t 검정과 Borich 요구도 공식을 통한 우선순위 분석, The Locus for Focus 모델을 활용한 요구도의 상위 수준을 결정하였다. Borich 요구도와 The Locus for Focus 모델을 활용한 최우선 순위의 작업은 총 8개로 ‘고압판넬 차단기 유지보수하기’, ‘고압판넬 계전기 유지보수하기’, ‘고압판넬 계기류 유지보수하기’, ‘plc H/W 유지보수하기’, ‘plc S/W 유지보수하기’, ‘plc network 유지보수하기’, ‘드라이브 H/W 유지보수하기’, ‘드라이브 S/W 유지보수하기’ 로 확인되었다. 본 연구를 통해 전기정비직 종사자의 DACUM 직무분석과 요구분석 결과 교육적 요구가 확인되었다. 이를 바탕으로 직무교육과정 설계시 효율적이고 성과 있는 교육과정을 개발해야 한다. 다양한 전기관련 업무를 취급하고, 생산에 직・간접적으로 관여하는 전기정비를 담당하는 종사자들에 대한 인력양성의 중요성을 다시 한 번 일깨우는 계기를 제공함과 동시에 그들에 대해 전략적이고, 체계적으로 육성하기 위한 계획수립과 운영, 평가 측면에서 본 연구결과가 중요한 자료로 활용될 수 있을 것으로 기대한다. The purpose of this study was to figure out the recognition difference about the level of importance(priority) of task of electrical maintenance workers that are directly or indirectly involved in the production of H company. The way to continue the study, analyze the position, and gather information about the duties and tasks for the position. After that, find out required knowledge, skill, attitude, and tools to perform the task. And then, make a priority from the training needs analysis through a survey. To implement the project, investigate duties through the DACUM job analysis and find out 4 of their duties, 33 tasks and conducted a survey. After that, we went through the verification of task and training needs analysis. The subjects were electrical maintenance workers at H company, and the committee for DACUM job analysis consisted of a facilitator, coordinator and 7 professionals of the field with over 19 years of experience each. Also, 5 work site management staff experts participated in the verification process of the result afterwards. The survey consisted of 342 electrical maintenance workers. Only 256 out of 342 participated in the survey. However, only 222 of those were used in final analysis. The first result of this study confirmed that the 4 duties were ‘power receiving and distribution maintenance’, ‘automatic control maintenance’, ‘electric device maintenance’, and ‘measuring device maintenance’ and 33 tasks that are most important to an electrical maintenance worker’s duty. Second, deducted knowledge, skill, attitude, and tools that are required to perform the 33 tasks. Third, to detect the priorities of the tasks of electrical maintenance workers, analyze priority based on the examination, Borich Needs Assessment Model and used The Locus for Focus Model to make a decision of superordinate standard. It confirmed that the top priority has 8 tasks based on Borich Needs Assessment Model and The Locus for Focus Model and they are ‘high voltage circuit breaker panel maintenance’, ‘high voltage relay panel maintenance’, ‘high voltage instruments panel maintenance', ‘plc H/W maintenance’, ‘plc S/W maintenance’, ‘plc network maintenance’, ‘drives H/W maintenance’, ‘drives S/W maintenance’. The training needs was confirmed through the DACUM job analysis and needs analysis of the study results for the electrical maintenance workers. Based on this study, it should develop a productive curriculum when we plan the competency curriculum. In conclusion, this study provided the opportunity of the importance of human resource training for electrical maintenance workers that handle a variety of electrical works that are directly or indirectly involved in the productions. Also, the results of these studies are expected to be utilized as a useful reference for planning and management, and evaluation for strategic and systematic development of electrical maintenance workers.