A Combined Maintenance Strategy Considering Spares, Buffer, and Quality

2021 ◽  
pp. 1748006X2097281
Author(s):  
Shuyuan Gan ◽  
Bolun Wang ◽  
Zhifang Song
Keyword(s):  
Product Quality ◽  
Model Simulation ◽  
Optimal Solution ◽  
Spare Parts ◽  
Inventory Level ◽  
Maintenance Policy ◽  
Cost Rate ◽  
Qualification Rate ◽  
Maintenance Model ◽  
The Mathematical Model

This paper studies an innovative maintenance model for an upstream machine in a common production system. Multiple system-wise features are integrated in the model, including maintenance, spare parts, buffer inventory, and product quality. The objective is to minimize the system expected cost rate by determining the optimal inspection interval, preventive maintenance threshold, corrective maintenance threshold, reorder level of spare parts, maximum stock level of spare parts, and maximum inventory level of the buffer. In this maintenance model, both the hazard rate and the product qualification rate can trigger maintenance activities. The well-known proportional hazard model (PHM) is adopted to describe the state of the upstream machine. The effect of machine state on product quality is explicitly characterized. Due to the complexity of the mathematical model, simulation and a genetic algorithm are employed to determine the optimal solution. A case study of bearings is presented to demonstrate the performance of the proposed maintenance policy. The results show that this policy is practical and can reduce system cost significantly.

scholarly journals A condition-based maintenance model with past-dependent imperfect preventive repairs for continuously deteriorating systems

2019 ◽  
Vol 234 (2) ◽  
pp. 333-358 ◽  
Author(s):  
Khac Tuan Huynh ◽  
Antoine Grall
Keyword(s):  
Special Kind ◽  
Condition Based Maintenance ◽  
Maintenance Cost ◽  
Engineering Practice ◽  
Imperfect Maintenance ◽  
Maintenance Policy ◽  
Cost Rate ◽  
The One ◽  
Maintenance Model ◽  
Deteriorating Systems

Most condition-based imperfect maintenance models developed over the last few decades are memoryless in the sense that maintenance efficiency is completely [Formula: see text]-independent of previous interventions. However, many maintenance activities exhibit their past dependency in engineering practice, and this significant property should not be ignored in maintenance modeling. In this spirit, our aim is to develop a condition-based maintenance model for continuously deteriorating systems subject to a special kind of past-dependent imperfect repairs. Such a repair can put the system back to a deterioration level better than the one at just before the current repair, but worse than the one reached at the last repair. Besides, inspection and replacement are memoryless actions available for the system. They result in different effects on the system deterioration and incur different costs. To achieve high economic performances in the long term, these actions are coordinated into a control-limit deterioration-based maintenance policy. Its long-run maintenance cost rate is analytically evaluated using the semi-regenerative process theory. Numerous sensitivity studies to maintenance costs and to system characteristics give a thorough understanding about the policy behavior. Furthermore, comparisons with more classical policies justify the importance of incorporating the past dependency in maintenance modeling.

scholarly journals Modeling Spare Parts Demands Forecast under Two-Dimensional Preventive Maintenance Policy

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Qiwei Hu ◽  
Yongsheng Bai ◽  
Jianmin Zhao ◽  
Wenbin Cao
Keyword(s):  
Preventive Maintenance ◽  
Spare Parts ◽  
Two Dimensional ◽  
Maintenance Policy ◽  
Calendar Time ◽  
Maintenance Practice ◽  
Preventive Maintenance Policy ◽  
The Mathematical Model ◽  
Novel Model

In maintenance practice, there is such a situation where the spare parts replacement should be carried out at the scheduling time of calendar or usage for whichever comes first. The issue of two-dimensional preventive maintenance usually was not addressed by traditional methods, and at present, few studies were focused on this very topic. Based on these considerations, this paper presented the two-dimensional preventive policy where replacements of spare parts are based on both calendar time and usage time. A novel model was developed to forecast spare parts demands under two-dimensional preventive maintenance policy, and a discrete algorithm was presented for solving the mathematical model. A case study was given to demonstrate its applicability and validity, and it was showed that the presented model can be used to forecast spare parts demands as well as to optimize spare parts and preventive maintenance jointly.

scholarly journals Joint Optimization of Preventive Maintenance and Spare Parts Inventory with Appointment Policy

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Jing Cai ◽  
Yibing Yin ◽  
Li Zhang ◽  
Xi Chen
Keyword(s):  
Inventory Management ◽  
Preventive Maintenance ◽  
Spare Parts ◽  
Combination Method ◽  
Joint Optimization ◽  
Inventory Level ◽  
Cost Rate ◽  
Proposed Model ◽  
Spare Parts Inventory ◽  
The Cost

Under the background of the wide application of condition-based maintenance (CBM) in maintenance practice, the joint optimization of maintenance and spare parts inventory is becoming a hot research to take full advantage of CBM and reduce the operational cost. In order to avoid both the high inventory level and the shortage of spare parts, an appointment policy of spare parts is first proposed based on the prediction of remaining useful lifetime, and then a corresponding joint optimization model of preventive maintenance and spare parts inventory is established. Due to the complexity of the model, the combination method of genetic algorithm and Monte Carlo is presented to get the optimal maximum inventory level, safety inventory level, potential failure threshold, and appointment threshold to minimize the cost rate. Finally, the proposed model is studied through a case study and compared with both the separate optimization and the joint optimization without appointment policy, and the results show that the proposed model is more effective. In addition, the sensitivity analysis shows that the proposed model is consistent with the actual situation of maintenance practices and inventory management.

Research on maintenance optimal policy based on product quality control

2016 ◽  
Vol 232 (5) ◽  
pp. 899-908 ◽  
Author(s):  
Xiaomei Yang ◽  
Jianchao Zeng
Keyword(s):  
Genetic Algorithm ◽  
Quality Control ◽  
Product Quality ◽  
Quality Characteristic ◽  
Maintenance Policy ◽  
Product Quality Control ◽  
Periodic Inspection ◽  
Optimal Maintenance ◽  
Maintenance Model ◽  
Degradation State

According to the correlation between product quality and equipment degradation state, an equipment maintenance policy is designed by integrating periodic equipment inspection and product quality control. In this policy, np-chart is used to monitor the abnormal shift of the product quality characteristic based on periodic inspection of the equipment. By considering the inspection result of the product quality shift and equipment degradation state, the corresponding maintenance action is chosen. Furthermore, the optimal maintenance model based on product quality control is proposed and is solved with genetic algorithm. The experimental results validated the feasibility of this model.

Maintenance optimization of a production system considering defect prevention and spare parts ordering

2021 ◽  
pp. 1748006X2110291
Author(s):  
Shuyuan Gan ◽  
Xinzhou Zhang ◽  
Lan Chen
Keyword(s):  
Production System ◽  
Production Quality ◽  
Spare Parts ◽  
Production Cycle ◽  
Efficient Production ◽  
Imperfect Maintenance ◽  
Maintenance Policy ◽  
Inventory Cost ◽  
Cost Rate ◽  
Defect Rate

An innovative maintenance policy is proposed in this paper. This policy can involve spare parts ordering, production quality, and buffer inventory for an efficient production system. In the system, certain batches are required to be produced, and when each batch is finished, a determination is made whether maintenance is needed. The machine state deteriorates with the number of completed batches, and it can be improved by performing maintenance. Two types of maintenance activity, replacement and imperfect maintenance, can be selectively chosen to minimize cost. The defect rate of each batch is related to the number of completed production batches. An innovative concept, defined as the “virtual number” of completed production batches, is used to establish a link between maintenance and defect rate. Monte Carlo simulation and enumerative search is then used to determine cost-effective spare parts ordering and maintenance policies to minimize the cost for the production cycle. Finally, numerical examples are presented to demonstrate the model and to conduct sensitivity analysis. We find that in situations with a high buffer inventory costs, spare parts should be ordered late. When increasing the buffer inventory cost, more replacements should be performed compared to imperfect maintenance. Also, the buffer inventory cost rate and replacement duration time effect the rate of defective products significantly. These two parameters should be kept small, and controlled, if a very low defect rate is needed.

Availability analysis and maintenance optimization for multiple failure mode systems considering imperfect repair

2021 ◽  
pp. 1748006X2110127
Author(s):  
Qingan Qiu ◽  
Baoliang Liu ◽  
Cong Lin ◽  
Jingjing Wang
Keyword(s):  
Failure Modes ◽  
Maintenance Cost ◽  
Imperfect Maintenance ◽  
Maintenance Policy ◽  
Cost Rate ◽  
Availability Analysis ◽  
Long Run ◽  
Optimal Maintenance ◽  
Maintenance Policies ◽  
Periodic Inspections

This paper studies the availability and optimal maintenance policies for systems subject to competing failure modes under continuous and periodic inspections. The repair time distribution and maintenance cost are both dependent on the failure modes. We investigate the instantaneous availability and the steady state availability of the system maintained through several imperfect repairs before a replacement is allowed. Analytical expressions for system availability under continuous and periodic inspections are derived respectively. The availability models are then utilized to obtain the optimal inspection and imperfect maintenance policy that minimizes the average long-run cost rate. A numerical example for Remote Power Feeding System is presented to demonstrate the application of the developed approach.

Optimal Parameter Design of Solder Residue in Flip Chip Process by Using Taguchi Method

2010 ◽  
Vol 443 ◽  
pp. 543-548
Author(s):  
Jian Long Kuo ◽  
Kai Lun Chao ◽  
Chun Cheng Kuo
Keyword(s):  
Taguchi Method ◽  
Product Quality ◽  
Manufacturing Process ◽  
Flip Chip ◽  
Optimal Parameter ◽  
Experimental Testing ◽  
Signal To Noise Ratio ◽  
Optimal Solution ◽  
Passive Component

Because the solder residue was found in the manufacturing process which greatly affected the product quality, the purpose of this paper was to make the product quality improved and to find an optimal solution for process parameters in the flip chip process. The experimental testing was based on SMT manufacturing process. The amount and size of solder left on passive component in the process of manufacturing were considered as the quality traits. Since too many solders left on the passive component side during flux cleaning process, it was possible that the balling would be flowed into the chip, which caused the bump short in the chip and affected the quality of the product. In this paper, orthogonal array by using Taguchi method is adopted as the effective experimental method with the least experimental runs. Also, based on the quality evaluation of signal-to-noise ratio, the ANOVA is used to evaluate the effects of quality target according to the experimental results. The results reveal that the optimization in the process is confirmed. Therefore, this study can effectively improve the solder residue in semiconductor manufacturing process.

Joint optimization of components redundancy, spares inventory and repairmen allocation for a standby series system

2018 ◽  
Vol 233 (4) ◽  
pp. 623-638
Author(s):  
Xian Zhao ◽  
Jing Zhang ◽  
Xiaoyue Wang
Keyword(s):  
Optimal Solution ◽  
Optimal Number ◽  
Joint Optimization ◽  
Series System ◽  
Inventory Policy ◽  
System Availability ◽  
Cold Standby ◽  
Batch Ordering ◽  
The Mathematical Model ◽  
Warm Standby

In the past, redundancy, inventory and maintenance are often considered separately to improve the system availability. Recently, a few joint optimization papers have emerged, but they only considered hot-standby redundancy, one-for-one-ordering inventory policy and the case of single repairman. In order to deepen the previous research, this article formulates a joint optimization model of components redundancy, spares inventory and repairmen allocation for a standby series system with an objective of maximizing system availability. As to the components redundancy, hot-standby, warm-standby and cold-standby are considered, respectively. A more general batching ordering inventory policy is adopted and the number of repairmen is added as a new element. By continuous time Markov process, related reliability probability indices are derived. Then the mathematical model is constructed and branch-and-bound method is employed to solve the optimal solution. Finally, we conduct analysis and comparison for different numerical examples and obtain the following results: cold-standby and warm-standby redundancy yield higher availabilities compared to hot-standby under the same conditions. The optimal batch ordering inventory policy is better than optimal one-for-one-ordering inventory policy if the spares replenishment rate is not high enough. Moreover, an optimal number of repairmen, which is always more than one, can be achieved to enhance the efficiency of maintenance.

scholarly journals Pengendalian Persediaan Untuk Mengurangi Biaya Total Persediaan Dengan Pendekatan Metode Periodic Review (R,s,S) Power Approximation Pada Suku Cadang Consumable (Studi Kasus : Job Pertamina Talisman Jambi Merang)

2017 ◽  
Vol 4 (1) ◽  
pp. 8
Author(s):  
Adhi Putra Mahardika ◽  
Muhammad Nashir Ardiansyah ◽  
Efrata Denny S. Yunus
Keyword(s):  
Service Level ◽  
Spare Parts ◽  
Gas Production ◽  
Inventory Level ◽  
Periodic Review ◽  
Inventory Cost ◽  
Turbine Engine ◽  
Total Cost ◽  
Gas Processing ◽  
Power Approximation

Spare parts is one of the production support components which plays an important role for the survival<br />of gas production in the gas processing facility owned by SKN JOB Pertamina Talisman Jambi Merang. The<br />high inventory level increased the high inventory cost for the industry which get the benefit from the efficiency<br />of processes and resources. This research involved consumable spare parts for Solar Turbine engine as much<br />as 25 SKUs with demand character patterned lumpy demand and Poisson distribution. The implementation<br />of policies using Periodic Review (R, s, S) with Power Approximation approach in the inventory system<br />capable to generate a lower total cost inventory by pressing the backorder volume, the booking volume and the<br />inventory levels in a balanced manner. Calculation of Periodic Review (R, s, S) with Power Approximation<br />approach resulted inventory parameter which was able to press the total cost of inventory at 8.54% lower and<br />increase the service level by 1.11%.

scholarly journals A Fuzzy EPQ Model for Non-Instantaneous Deteriorating Items where Production Depends on Demand which is Proportional to Population, Selling Price as well as Advertisement

2019 ◽  
Vol 10 (5) ◽  
pp. 1679 ◽  
Author(s):  
Abhishek Kanti Biswas ◽  
Sahidul Islam
Keyword(s):  
Optimal Solution ◽  
Inventory Level ◽  
Selling Price ◽  
Distance Method ◽  
Defective Items ◽  
Holding Cost ◽  
Epq Model ◽  
Optimal Inventory Level ◽  
Cost Parameters ◽  
Total Average

The inventory system has been drawing more intrigue because this system deals with the decision that minimizes the total average cost or maximizes the total average profit. For any farm, the demand for any items depends upon population, selling price and frequency of advertisement etc. Most of the model, it is assumed that deterioration of any item in inventory starts from the beginning of their production. But in reality, many goods are maintaining their good quality or original condition for some time. So, price discount is availed for defective items. Our target is to calculate the total optimal cost and the optimal inventory level for this inventory model in a crisp and fuzzy environment. Here Holding cost taken as constant and no-shortages are allowed. The cost parameters are considered as Triangular Fuzzy Numbers and to defuzzify the model Signed Distance Method is applied. A numerical example of the optimal solution is given to clarify the model. The changes of different parameters effect on the optimal total cost are presented and sensitivity analysis is given.JEL Classification: C44, Y80, C61Mathematics Subject Classification: 90B05

Sign in / Sign up

Export Citation Format

Share Document