Takt Time Research Articles

Productivity improvement through lean manufacturing tools in Ethiopian garment manufacturing company

The major purposes of the use of lean production are to increase productivity, improve product quality, reduce inventory, reduce lead time and eliminate manufacturing waste or non-value-added activities. Case study garment manufacturing company follows the conventional production system and is facing problems concerning, long production lead times, poor line balancing, long transportation and material movement, etc. The main objective of this research is to enhance productivity by minimizing and eliminating problems and wastes found in company and increase market competency by using different lean manufacturing tools like; motion study, work standardization through time study, and line balancing. In the investigation, high work-in-process, poor line balancing, high cycle time and production lead time, unbalance work distribution/assignment, in the company have been found out. After implementation of some lean tools, results observed involve, cycle time is reduced to 32.73%, cycle time is balanced with takt time, work stations are reduced to 14, through time study; SAM of product is standardized to 41 min., production lead time is reduced by 11.8% and productivity is increased by 16.66%. The implementation of the new manufacturing practices can lead to better product quality and greater participation by workers in efforts to improve manufacturing processes, the products, and the company as a whole. It is also examined its impact on the profit of the company by producing quality products and timely delivery, as well customer satisfaction.

Spatiotemporal Planning of Construction Projects: A Literature Review and Assessment of the State of the Art

Recently, new methods and technologies, including building information modeling (BIM) and lean management, have been introduced to the construction industry. Their objectives are to increase collaboration, ensure smooth flows of information, improve productivity, reduce different types of waste, and stabilize production. These constraints have forced the industry to gradually change by applying more adapted operational processes and contractual models that focus on value and by integrating the design, construction and operation phases. Traditional scheduling methods based on activities modelling have become less adapted to this new reality. As a result, complementary concepts have emerged, particularly the Last Planner system, takt time, space planning, and spatiotemporal scheduling. This paper presents an extensive review and an assessment of the state of the art of the spatiotemporal planning of construction projects. The paper categorizes the research efforts, presents a timeline of the most significant scientific developments in this domain, and addresses their possible impacts on the construction industry.

Selection of optimal capacity for reconfigurable machines during lean manufacturing

Presently manufacturing industries are facing the challenge of increased market volatility and unpredictability. Capacity control is an effective measure to address this problem by utilizing the flexibility in the plant capacity. This research paper proposes a genetic algorithm (GA) based methodology to optimally select levels of capacity for machines which are reconfigurable in nature. The objective function for the optimization problem is minimization of an error with takt time. Takt as a key feature of lean manufacturing is considered in the model to manufacture the products in a fixed rate as decided by their respective demands and available production time. A hypothetical numerical problem is illustrated to describe the selection methodology, GA computation steps and the solution procedure.

71‐3: Meeting Optical Testing Challenges of High‐Resolution µLED‐Displays

Novel display technologies come with new measurement challenges to meet the highest quality standards in mass production. Here we shine light on these challenges and discuss innovative testing solutions to assure highest display quality in production takt times. We present how single pixel analysis can improve display quality by using a statistical approach to nonuniformity of luminance as well as color metrology on sub‐pixel level. Applications for smartphone displays and microdisplays are discussed emphasizing the challenges of very small pixels and pixel pitches. Finally, calibration of light measuring devices are challenged with respect to the specific spectral properties of µLEDs and OLEDs.

Efficiency Improvement and Capacity Enhancement using Line Balancing Technique

Maximise the utilization of the resources by optimizing the working conditions and elimination of the waste is the ultimate goal of the lean manufacturing. In order to achieve this we have various tools which can be used as per the need of the project. In this paper we are going to optimize the use of resources by increasing the line efficiency by applying line balancing technique and achieving continuous flow. Increase in demand has set a new takt time which has given us an opportunity to redefine the flow of line and increase the line efficiency from 60.44% to 83.44%. We have used the results of method study to get modified times presented in the table, which helped to get balanced line with improved efficiency.

Execution of lean and industrial techniques for productivity enhancement in a manufacturing industry

In current global manufacturing scenario, every organization wants to fulfill their customer needs to retain their position in the market. Lead time plays a vital role to improve them in the global competitive market. The aim of this research work is to minimize the overall lead time of the product by finding out bottlenecks and to eliminate them. The important processes in the production line are work in progress, layout optimization and line balancing. The existing manufacturing techniques and the process of the product were studied thoroughly and then time study was followed. Based on the time study results TAKT time was calculated for the demand followed with current state VSM was drawn and the bottleneck stations were identified. After developing current state VSM, assembly line was balanced using flexible line balancing software. Further improvements were made with the lean techniques of fish bone diagram, Pareto chart and layout optimization. After the execution of the above lean techniques the future state VSM was drawn and observed that the lead time and value added time were reduced by about 15 and 16 min respectively.

Variable takt times in mixed-model assembly line balancing with random customisation

In turbulent times featuring increased customisation, higher demand volatility, and shortened product life cycles, companies gain a competitive advantage by adopting a single yet highly flexible assembly line. A cornerstone of today's production systems is determining the optimal takt time (or cycle time) by aligning the assembly pace with the desired level of output. In practice, most companies rely on a fixed takt time, even when the work content between models varies considerably. We show that, in contrast to a fixed takt system, variable takt times reduce not only labour inefficiencies but also the complexity of the mixed-model assembly line balancing problem. Inspired by our industry partner Fendt, an innovation leader in the global agricultural machinery market and benchmark for a wide range of industries, we define a generalisable mixed-integer programming model that accounts for key conditions neglected in previous research – in particular, random customisation through configuration-specific task times and assembly quality by assigning operator workloads to ‘zones’. Introducing such operator work zones reveals that firms need not face a time–quality trade-off whereby takt time must be prioritised over how well work is performed. Our numerical study and takt time sensitivity analysis document the effectiveness of this approach when its results are compared with those under Fendt's current takt times.

Research on Design and Application of Automatic Production Line for Mechanical Components

In order to meet the requirements of automatic processing for mechanical components manufacturing enterprises, the paper describes a design method of automatic production line. Firstly, the paper made the overall design of the automatic production line, takt time is calculated according to the annual production demand, and the analysis of device configuration and position layout of the production line was carried out based on the annual production requirement. Secondly, the paper selects types of CNC machines and industrial robots, and design structural of the silo, the temporary storage platform, the conveyor belt, the fuel injection and water removal. 3D model of each component and space layout of the production line are drawn by Solidworks software. Thirdly, the process flow of automatic production line was designed, and the CNC intelligent management system was developed to meet the requirements, which can monitor the process information such as takt time. Test is carried out after establishment of automatic production line, the test run finally shows that the automatic production line works stably and can meet the requirements of enterprise.

Lean Labour in AEC Industry: From Theory to Implementation

The architecture, engineering and construction (AEC) industry, in India is flourishing due to urbanization, industrialization and modernization. The orthodox concept of construction was design-bid builds method or Integrated Project Development methods have been replaced by “lean construction” concept. The lean concept adaptation in AEC is contemporary to the socialistic working tool of the Anthropocene epoch during mid of 20th century. The studies on lean concept is highly relevant in the present social and ecological prospective which promote environmental sustainability, labour manager coordination and collaboration. The lean concept can enhance production and productivity in construction industry through effective implementation of lean labour management. The concept emphasizes on coordination, collaboration, team spirit with humane approach to labour management. The concept results in lowering cost , reduction and elimination of wastage, higher level of motivation , retention of workforce , innovation and implementation of result oriented management practices and achieving customer’s delight. The Takt time and last planners system is to be introduced with lean labour. The construction works on its flow processes require the value stream such as 6M’s (Men, Material, Machines, Methods, Mother Nature (environment) and Measurement), working under 5T’s principle (transparency, teamwork, technology, time, which shall lead to transformations) to be implemented within the AEC sector from grass root to top.

Fabrication of Optimally Micro-Textured Copper Substrates by Plasma Printing for Plastic Mold Packaging

Micro-embossing using plasma printed micro-punch was proposed to form micro-groove textures into the copper substrate for plastic packaging of hollowed GaN HEMT-chips. In particular, the micro-groove network on the copper substrate was optimized to attain uniform stress distribution with maximum stress level being as low as possible. Three-dimensional finite element analysis was employed to investigate the optimum micro-grooving texture-topology and to attain the uniform stress distribution on the joined interface between the plastic mold and the textured copper substrate. Thereafter, plasma printing was utilized to fabricate the micro-punch for micro-embossing of the micro-grooving network into the copper substrate as a designed optimum micro-texture. This plasma printing mainly consisted of three steps. Two-dimensional micro-pattern was screen-printed onto the AISI316 die surface as a negative pattern of the optimum CAD data. The screen-printed die was plasma nitrided at 673 K for 14.4 ks at 70 Pa under the hydrogen-nitrogen mixture for selective nitrogen supersaturation onto the unprinted die surfaces. A micro-punch was developed by mechanically removing the printed parts of die material. Then, fine computer numerical control (CNC) stamping was used to yield the micro-embossed copper substrate specimens. Twelve micro-textured substrates were molded into packaged specimens by plastic molding. Finally, gross leak testing was employed to evaluate the integrity of the joined interface. The takt time required to yield the micro-grooved copper substrate by the present method was compared to the picosecond laser micro-grooving; the former showed high productivity based on this parameter.

Lean Manufacturing Model for production management to increase SME productivity in the non-primary manufacturing sector

Currently, there is a large percentage of small and medium-sized enterprises (SMEs) in the Peruvian textile market that show economic loss because of the payment of penalties to customers, which are incurred owing to the delay in the delivery of order batches. This is due to poor production management and a lack of focus. The manufacturing sector is essential because of its high contribution to the country’s gross domestic product. Currently, SMEs do not employ methodologies that help improve production and process management as they do not realize how important and necessary the methodologies are, in addition to how complex these may be. Therefore, this paper will propose a production management model designed for SMEs in this sector, based on Lean methodology where the objective is time reductions and production increases as well as exerting changes to the organizational culture. Thus, this model will help organizations to avoid incurring economic losses because of the payment of penalties for orders not delivered on time. To validate the present model, a time simulation was performed in the manufacturing area of a textile company. The result of this project was positive, since there was a 25% increase in productivity and a 20% reduction of takt time with respect to the initial data.

Planning for Improvement of Carton Box Production Process using Lean Manufacturing Approach to Increase Production Results at PT. Kati Kartika Murni

Abstract—PT. Kati Kartika Murni is a company engaged in the packaging industry. This company applies a make to order (MTO) system. Carton Boxes are the focus of research because it have the highest number of requests by 55%. Problems faced by PT. Kati Kartika Murni namely the number of customer requests not yet met. This research was conducted to increase the production of carton boxes to 3600 boxes. Increasing the amount of production is done by lean manufacturing approach, namely by identifying waste and eliminating existing waste. Manufacturing lead time before repair is 17811.7 seconds, process cycle efficiency before repair is 44.4489%, and takt time is 4.645 seconds. The number of production before the design of repairs is 3379 boxes, where orders have not been fulfilled with the available time. The highest waste based on the waste assessment model and value stream analysis tools are defect and transportation. The analysis was conducted using the Failure Mode and Effect Analysis (FMEA) method to determine the type of waste that needs to be eliminated. The highest RPN of 448 is the faded color defect in the flexo process and the second highest RPN of 392 is the overlap defect in the corrugating process. Waste transportation analysis using FMEA method shows the highest RPN value of 448, namely at the time of operation and material movement on the production floor. The design of improvements to eliminate waste transportation is to add a roller conveyor functioning as material handling between work stations. One piece flow addition for the corrugating process to flexo. After an improvement plan is made, the Manufacturing lead time is 15634.2 seconds and the Process cycle efficiency is 50.64%. The amount of production after the design improvement is 3850 boxes, where orders have been fulfilled with the available time.

Balancing, sequencing, and job rotation scheduling of a U-shaped lean cell with dynamic operator performance

Performance of a manufacturing cell is dependent on an efficient layout design, and optimal work schedules. However, the operator-dependent factors such as learning, forgetting, motivation, and boredom, can considerably impact the output of the system. In this study, we consider heterogeneous operators with dynamic performance metrics and integrate the job assignment, and job rotation scheduling problems, with the balancing and production sequencing in a U-shaped lean manufacturing cell. We present a novel multi-period nonlinear mixed-integer model to minimize the deviations from takt time, and the number of operators, in a finite planning horizon. An efficient meta-heuristic approach is developed to solve the problem and the results are compared to a static case where no human factor is included. Our computational results demonstrate that including the operator-dependent metrics can improve the performance of the cell design. We conduct a sensitivity analysis of the scheduling parameters including, rotation frequencies, takt time, cell size, and task types, and derive that the obtained solutions with the static settings, are not sufficient for an efficient lean cell design in the presence of dynamic human factors.

Novel availability and performance ratio for internal transportation and manufacturing processes in job shop company

Purpose: Purpose of this study includes the quantification of the impact of transportation efficiency onto the workstations the transportation serves in term of throughput and total lead time elapsed by product. Besides, it aims to synchronize the capacity available among workstations throughout a production line by studying the upper limit of throughput could be afforded by each workstation as well as their connection with each other. This study is also done on the purpose of promoting fulfillment of customer demand at shorter delivery time and minimal equipment utilization. Investigation on implementation of Overall Equipment Effectiveness (OEE) in an aerospace part-manufacturing company is studied to track out the potential opportunities to be improved.Design/methodology/approach: Site observation is conducted on all the five manufacturing workstations in the aforementioned aerospace part manufacturing company. Time data of both automated processes and manual processes are collected and they are used to construct simulation model. From that, various scenarios of transportation efficiency are simulated in Experiment 1. In addition, Experiment 2 is also set to examine the maximum capacity of each workstation. All of these are to highlight the relationship between workstation and processes and to verify the condition of imbalanced capacity among workstations in the company. In short, this has necessitated the integration of workstation and transportation activities within the company. These are followed by proposal of measures to quantify the wastes identified.Findings: The paper finds that implementation of OEE alone does not consider the reasonability of customer demand fulfillment. The results show that both transportation efficiency and imbalanced capacity throughout production system are not emphasized by OEE implementation in the case company. Therefore, responsibility of all workstations and transportation process in delivering demand on time are quantified. Transportation process which serves as the connectors of manufacturing processes is quantified and monitored by proposed Transportation Measure (TM) whereas workstations are measured using novel availability and performance ratio.Research limitations/implications: Future research should be conducted to examine the impact of other station within a company such as warehouse and logistic department to the performance of equipment and materials in manufacturing workstation. Besides, the material availability as well as the skills or performance of man power could be further incorporated into the measures to consider all the entities involved in manufacturing processes.Practical implications: The proposed availability and performance ratio for both transportation and manufacturing processes, which are related to each other, help in promoting better effectiveness of production system in terms of production amount and lead time. Besides, reasonable utilization equipment and minimal consumption of material are incorporated in the measures to promote Lean way in fulfilling customer demand. The effectiveness of entire production line is examined as a unity with joint responsibility under varying transportation efficiency and cycle time of each workstation. Both measures could be implemented together to optimize the production system and quantify the hidden wastes which are neglected in the OEE implementation.Originality/value: The novel availability and performance ratio are proposed to consider customer demand, historical equipment utilization and Takt time of each workstation to examine the possibility and reasonability of demand fulfillment. This prevents both over-processing and overproduction issues which are invisible in OEE. Furthermore, delay propagation throughout production system and interrelationship between processes are quantified under transportation measure. Other novelty of the paper is that it monitors the waiting time and lead time spent in each workstation at the same time considering utilization of workstation. The proposed Transportation Measure (TM) aims to reduce the queue length and waiting time at destination workstation at minimal utilization of forklift. It also promotes less capacity investment in transportation and prioritizes its scheduling according to urgency of destination workstation.

A Novel Technology in Lean Manufacturing

In today’s emerging world, as the demands and expectations of the people grow higher and higher every day, so is the competition. Thus to face the demand and to be competitive & survive in the market, industries have to produce superior quality components without producing waste. This leads every manufacturer to optimize and standardize the processes of every component being produced. One such concept employed is “Lean Manufacturing”. In this paper a novel tool in lean manufacturing is applied. The processes are continuously monitored and collected necessary data to generate VSM and declare the CSM based on the available data. Then the takt time graph and the balanced time – Cycle time – Downtime graph were plotted with the help of which, the scopes for improvements are identified and then the targets are obtained. The FSM is also drawn and a time plan for projects is prepared and monitored continuously. Based on the type of process and the project, different tools are adopted to reduce the cycle time, downtime, waste and thereby increase the productivity. By implementing newer tools, the future demand of the process was successfully proved to be met by the existing line itself and the need of an additional line was defeated, thereby making monetary savings. By implementing this system, the productivity can be constantly increased.

A statistical analysis of critical quality tools and companies’ performance

When implementing continuous improvement methodologies such as Lean and Six Sigma, one crucial aspect is to determine which quality tools to implement to achieve a performance objective. The purpose of this article is to determine the critical quality tools and their effects on companies’ performance. The data was collected using a questionnaire that was conducted within French industries, in Pays de la Loire region. A multiple correspondence analysis is performed first to explore and describe the data. Second, ordinal regression models are developed to determine what are the critical quality tools that support the companies’ performance in terms of quality, cost, and productivity. This case study shows that the critical quality tools to improve quality performance would be implementing One Piece Flow and GEMBA tools. Next, implementing Value Stream Mapping and Takt Time tools would significantly reduce the cost compared to not implementing those tools. The analysis shows improvement in productivity can be achieved by implementing KANBAN tool. The findings have the potential to guide companies to determine which quality tools are most likely effective in improving quality, productivity, and reducing cost.

Lean practices implementation in aerospace based on sector characteristics: methodology and case study

Lean production (LP) consists of very useful techniques; however, its implementation can significantly vary from one sector to another or from one practitioner to another. Although several lean experiences exist in aerospace, no specific method has been developed to adapt lean tools to the characteristics of the aerospace sector. This study uses a case based approach to analyse the implementation of lean practices in a company operating in the aerospace industry. The overall characteristics that motivate current aerospace companies to pursue lean conversions are identified – market demand, product diversification, product complexity, safety focus and agile supply chain. This paper aims at building a methodology including identified steps and their analysis to sustain the lean implementation. It is based on the analysis of the industrial context, which is linked to different practices and tools issued from LP. Apart from the aerospace sector, the methodology can also be adjusted and adopted by other sectors. Lean practices, such as the cellular layout, the one-piece flow, visual management, takt time, standardization, multiskills, poka yoke and SMED, were used in the proposed model and yielded significant gains. The defect rate dropped by 66%, the cycle time was reduced with 43% of savings, waste elimination was achieved, and the work-in-progress (WIP) inventory decreased. Furthermore, the illustrated impact of the lean manufacturing implementation on extending lean thinking to the logistics department presented 50% savings in transportation-truck costs. It serves as a proof of concept for the expansion of lean thinking.

Lead time reduction through lean techniques on filter drier component by modifying fixture design – Case study

In a manufacturing company, it is important to improve the cycle time and achieve the projected lead time. Delivering the goods on time and in good quantity is important factors to satisfy the customer. To stay inside the competitive market consumer orders is vital. So customer pleasure is considered as one of the many objectives of a company. In this paper filter drier has been taken into account and its cycle time is studied. Current state Value stream mapping (CSVSM) for existing methodology has been plotted and the bottleneck of the process was found during the cap assembly. Based on customer demand, Takt time and production time is plotted. The cup assembly process takes more time than the Takt time. The problem for time taken was analyzed with lean tools and Cause and effect diagram. A new fixture design was created to reduce the cycle time of the cup assembly. Future state value stream mapping (FSVSM) was plotted. The production of filter drier has been increased from 818.3 numbers to 1285 numbers and the bottleneck process time has been reduced from 33 s to 21 s.

Reduction of Cycle Time in Vehicle Engine Assembly LineUsing Karakuri Kaizen

Just In Time (JIT) based automotive manufacturing companies use the takt time and cycle time as indicators of their manufacturing performance. This study explores the vehicle engine assembly line for Station 2 Cylinder Block Products, which has a cycle time of 184 seconds, while the company targets a 180 second for takt time. Though ideally, the cycle time should not exceed the takt time. This research aims to identify the Non-Value Added (NVA) activities in Station 2 and minimize them with Karakuri Kaizen. The results of the Process Activity Mapping (PAM) show that Station 2 Cylinder Block has 16 Value Added (VA) activities, 19 Necessary Non-Value Added (NNVA) activities, and 7 Non-Value Added (NVA) activities with a manufacturing cycle effectiveness (MCE) 78%. Based on the activity mapping, the researchers find the primary causes and designed a proposed improvement using the Karakuri Kaizen method to reduce two NVA activities. The company can speed up the cycle time at Station 2 Cylinder Block to 180 seconds and the MCE to 80% by implementing Karakuri Kaizen.

Productivity improvement in poly-cover packing line through line balancing and automation

Improving productivity is a popular topic for any kind of company to enrich the income through reduced workload and the development of new strategies for a specific business. Historically Industrial Engineers have a strong concern in Productivity Improvement through Work-Study. It is common and almost has become mandatory in most of the companies to meet the competitive market. Work-study also facilitates various improvements like Waste identification and elimination, Automation, Takt time, Line balancing, etc. which improves the competitive edge of the Organizations in its market. Hence, this study thus allows the bottleneck to be noticed and suggests a suitable system for improving productivity. By applying line balancing and automation in the enterprise at Poly-cover packing line Rs. 7.2 Lakhs per annum for man-power is saved.