Process Lead Time Research Articles

Development and Improvement of a Production Company (and their Product) Based on the Value Stream Mapping of Business Processes

Abstract Value stream mapping is one of the basic tools used in the processes improvement or design – in accordance with the Lean concept. This paper presents a model of designing production processes and introducing new products to the market based on the analysis of the value streams flow in the production process. Particular attention was paid to the importance of input data necessary to plan a properly functioning production process, which results in a high-value product (from the customer’s point of view). In the paper also the list of all the most important tools supporting all stages of designing new production processes or improving existing processes has been presented. Also the advantages of big pictures analysis using was highlighted. In this case value stream mapping and big picture analysis were oriented on quality in the product development process and contribute to: creating value (based on customer requirements) while maintaining timely deliveries and constant costs (Value Stream Mapping), sustainable use of tangible and intangible resources (removing waste at the design stage). However, from the company point of view, and particular in the cost level, the product can gain value because a lower input is required for its production. After improvement, the process lead time has been shortened in an area where value was not added, but the consequence of implementing the change is an increase in the production volume while maintaining the process transition time – therefore, unit costs of production will change.

IMPLEMENTASI LEAN SIX SIGMA UNTUK MENURUNKAN VARIASI DAN WAKTU PROSES PENGADAAN OBAT DI INSTALASI FARMASI RUMAH SAKIT ISLAM AMAL SEHAT SRAGEN

Background: Drug management needs to be done to prevent stock out, over stock, and drug purchases due to emergency conditions. Reports of drug management problems at Amal Sehat Sragen Hospital are stock outs resulting in immediate drug purchases and patients do not get the drug as they should. Lean Six Sigma combines two methodologies to help speed up certain processes so they can solve problems faster while creating more value for customers. When combined, these create a powerful methodology for managing a business and completing tasks on time, on budget, saving money, adding value and increasing productivity.
 Objectives: Assessing the implementation of Lean Six Sigma to reduce variation and processing time for drug procurement at the Pharmacy Installation of Amal Sehat Sragen Hospital.
 Methods: The method used in this study is a mixed methods with a Participatory Action Research (PAR) approach.
 Results: The results of the sample data that has variations and processing time are correlated with criticality, cost, and performance values to obtain Importance Index (II) values. Calculation of Importance Index (II), before implementation, 3 items with high Importance Index (II) values were obtained, namely "Gabapentin 300mg" (8.7), "Metformin 500mg (11.8), and "Lisinopril 5mg" (10.7) which decreased after implementation to “Gabapentin 300mg” (4.5), “Metformin 500mg (3.2), and “Lisinopril 5mg” (5.3). Assessment of the effectiveness and efficiency of drug procurement by measuring the lead time in cycle I was 9 days 23 hours 25 minutes, decreasing to 4 days 7 hours 50 minutes in cycle III. The efficiency measure based on the Value-added ratio (VAR) in cycle I was 14% and increased to 34% in cycle III.
 Conclusions: The implementation of Lean Six Sigma with DMAIC (Define, Measure, Analyze, Improve, Control) and Participatory Action Research approaches (three cycles) was able to reduce variations in the drug procurement process (critical criteria, performance, and cost) and overall lead time in the drug procurement process at Amal Sehat Sragen Hospital.

Optimization of the Production Management of an Upholstery Manufacturing Process Using Lean Tools: A Case Study

This study aims to address the challenge of implementing Lean philosophy in Small and Medium Enterprises (SMEs) and fill the research gap regarding Lean application in vehicle seat upholstery maintenance/repairing processes. The Lean tools applied in a case study of an upholstery industry of vehicle seats were as follows: Value Stream Mapping, Spaghetti Diagram, Gemba, 5S, Standardized Work, Kaizen, Kanban, and Poka-Yoke tools. A Decision Support Method using Excel Microsoft 365 was developed for improved stock control. A GUT Matrix was formulated to prioritize improvement opportunities, aiding prompt decision-making. This systematic approach enabled the company to address critical areas requiring swift attention. The results of Lean tools implementation led to a process waste minimization around 47%, and the process Lead Time decreased by approximately 26%, resulting in a 33% production increase. Thus, the Lean tools integration leads to substantial waste reduction, shorter process time, and increased production. The Decision Support Method enabled the company to efficiently monitor and manage its stock levels, thereby enhancing inventory management practices. This case study outlines the successful optimization of an upholstery production process in an SME by effectively applying Lean tools, highlighting its feasibility and benefits.

Penurunan Lead Time Manufacturing Dengan Pendekatan Lean Manufacturing Studi Kasus Di PT. MKM

In the industrial world, it is very important to pay attention to the efficiency of production capacity where the manufacturing lead time for making shoe outsole is influenced by activities that are not value-added (Non Value Added) and activities that are not value-added but necessary (Necessary Non Value Added) in which there is some extravagance that occurs. These activities are in the form of temporary storage in the cooling room and the process of reworking defective products. The method used is Lean Manufacturing, the tools used are Value Stream Mapping (VSM) and Process Activity Mapping (PAM). VSM is used to identify activities that have cycle times exceeding takt time, followed by mapping the Activity Mapping process to analyze activities that are not Value Added. Based on the results of research from 4110 seconds, the process lead time of 3600 seconds is a non-value added activity. The rework process and material storage in the cooling room were identified as having the largest value contributing to lead time, so rework must be eliminated. the percentage of Process Cycle Efficiency (PCE) has increased. The reduction of the finished sheet material process is cooled to the cooling room and the rework process can save about 60 minutes of working time. Saving working hours can increase outsole production capacity so that productivity increases and targets are achieved.Keywords: Lead Time Manufacture, Lean Manufacturing, Value Stream Mapping, Prose Activity Mapping. Process Cycle Activity.

System Dynamic Analysis of the Fleet Availability and Reliability Influence on the Lead Time of the Delivery Order Process

The inventory replenishment process in the warehouse becomes difficult if there is uncertainty. It can cause warehouse performance not to be as expected. The warehouse is an important part of the supply chain subsystem, which smooths the flow of goods from upstream to downstream throughout the system. This paper uses system dynamics modeling to analyze the replenishment of raw materials where there is randomness in availability and reliability and their effects on the delivery lead time of the fleet. The model obtained is much simpler but more robust when compared to the analytical-mathematical model or the discrete-events simulation. Tests on the model show that the model can behave as it should logically. Several experiments were conducted to see how fleet availability's reliability can affect the delay in receiving or delivery lead time. One interesting thing revealed is that reliability does not have to be 100%, but there is a certain minimum threshold for the system to perform well. This is different from availability, which must be 100%.

Reducing Manufacturing Lead Time With Lean Manufacturing Approach Case Study: CV Suho Garmindo

The purpose of this study is to reduce the Lead Time Manufacturing of mask products at CV Suho Garmindo. At this time it is known that Lead Time Manufacturing is influenced by Non-Value-Added activities and Necessary Non-Value Added activities in which there are several wastes that occur, these activities include the temporary storage process in the loading section, the process of reworking defective products and the transportation process. The method used is Lean Manufacturing, the tools used are Value Stream Mapping (VSM) and Process Cycle Activity (PAM). Value Stream Mapping is used to identify activities that have a cycle time greater than the takt time, followed by Process Cycle Activity mapping to analyze activities that are Non-Value Added activities. Furthermore, NVA activities are analyzed with 5W1H, and 5 why's tool to find out the root of the problem. Based on the research results from 126.1 minutes of lead time process 110 minutes is a non-value added activity. The rework process is identified as having the largest value of contributing lead time, so rework must be eliminated. After it is known that the root cause of the rework process is due to the ineffectiveness of the sewing process (bottleneck occurs), then for improvement the author proposes the needs of the available machines and man power. The changes are the number of machines from 9 to 10, sonday operators from 2 people to 1 person, finished stick operators from 2 people to 1 person, and funnel operators from 2 people to 4 people. Furthermore, the optimal layout improvement based on production flow is described. Due to research limitations, this research did not reach the implementation stage. So with the change in the number of machine requirements and available man power, it is expected that the rework process will be reduced so that the Manufacturing Lead Time can be reduced.

An implementation of lean technology to improve the lead time of syrup batching process and reduce hot fill line downtime

The research would present an effective performance of lean tools implementing in an Lemon Tea processing line of a Drink Industry as a case study. An improved strategy to reduce the lead time of syrup batching process and then reduce downtime on hot fill line would be considered as well as used. The DMAIC (Define - Measure - Analyze - Improve - Control) methodology would be followed. As the results, the lead time of syrup batching process was reduced from around 140 minutes to (after implementation of lean technology) 98 minutes, and downtime on hot fill line was also dropped significantly by approximately 50 percent. Besides, the production flow was optimized by minimizing several non value added activities and time such as waiting time at the bottleneck points, machine breakdown, queuing time, and other unnecessary waiting time. Eventually, this case study would be useful in developing a generic approach to design lean environment in management system of the studied drink industry organization.

Measurement of maintenance planning and control effectiveness using the Lean approach

Ineffective maintenance management can result in a backlog of maintenance work orders, inefficient activity prioritisations, and unnecessary outages. Making a strategic decision is challenging due to traditional procedures that only treated maintenance at a tactical level. Usually, the key performance indicator (KPI) measured for maintenance management is related to work order compliance. However, there is still less work focusing on measuring the effectiveness of Maintenance Planning and Control (MPC) processes. This paper aims to showcase a measurement of the maintenance effectiveness at offshore facilities using Lean methodology by measuring the lead time of sub-processes of MPC activities to evaluate existing practices, identify gaps and develop key recommendations. To this end, the lead time of the baseline MPC process is analysed and benchmarked with that of the improved MPC where new parameters to monitor and verify the process efficiency are included. The results show that a lead time improvement of close to 60% was achieved with the proposed methodology.

SIMULASI PERBAIKAN LEAD TIME PROSES PRODUK BUMPER MENGGUNAKAN VALUE STREAM MAPPING DAN PROMODEL DI PT. SUZUKI INDOMOBIL MOTOR

The development of the industry in this globalization era is very rapid, causing complex problems. The era of globalization requires all aspects of life to adapt to the development of more advanced times with the sophistication of its technology. One of the ways to increase excellence is to minimize waste in the production line. Beginning by describing the actual condition of the production line and trying to eliminate the waste in order to realize a lean value stream. The method used is a value stream mapping that is useful for seeing the processing time detail so that it knows the value added and non value added as well and Promodel software to simulate the proposed improvement given to improve the process lead time. Based on the current stream map that has been made known waste activities that occur is over process, inventory, and waiting. The front bumper assy panel of the Model Y9J at PT. Suzuki Indomobil Motor is the product with the highest demand for spare parts, where the lead time for stock is 21.2 days, and the lead time for processing is 1.14 days so it is necessary to make improvements using a Value stream mapping simulation, so stock lead time to 6.1 days and process lead time to 0.6 day.

Improving the efficiency of material transfer system using Value Stream Mapping (VSM): A case study in the shoe industry

This research was conducted in one of the shoe industries in Indonesia, which has a problem with material buildup in production material storage. The buildup of material can cause the production material transfer system less efficient. The research aims to identify waste in the production material transfer process using current state value stream mapping (VSM), recommend improvement strategies using future state VSM, and design a more efficient production material transfer system. First, we develop a causal loop diagram because it can map the problem. Then, we identify and fix the problem through value stream mapping for more efficient use of resources. The waste identified in the current state value stream mapping consists of waste of over-processing, waste of motion, and waste of useless transportation. In the future-state VSM, the lead time of the material transfer process is reduced by 840 seconds or 14 minutes, the cycle time of the material transfer process is reduced by 731 seconds or 12 minutes, the area needed is reduced by 43.2-meter square, and the total workforce reduced to two people. A 4-hour material transfer system is recommended as a more efficient production material transfer system.

Fast simulation of incremental sheet metal forming by multi-tooling

Fast and precise numerical analyses are necessary for virtual process design in the incremental sheet forming (ISF) process to extend its utilization effectively to industrial applications. Reliable process simulation ensures the short lead-time process advantage by ensuring the right products in the first attempt. Previous studies illustrate that explicit finite elements with mass or time scaling can reduce the simulation time without compromising the results. Still, the simulation time is much higher than the time consumed during real production. Keeping this in view, an approach of multi-tooling, which is rarely investigated, is focused on in this work to minimize the simulation time by utilizing the Abaqus software. The complete toolpath was split into equal segments, and one pair of tools was assigned to each segment. Instead of continuous movement in a single direction, as occurs in the case of single pair of tools, the tool was moving back and forth in the consecutive contours while moving simultaneously in the negative Z-direction in its designated segment. This concept was first trialed on the pyramid shape for sheet thickness variation, geometric precision, Mises stresses, equivalent strain, and forces. After verifying the model with the experimental results for some key quality attributes and simulation results based on single pair of tools (which was used as a reference computation as it represents the actual experiment), it was extended to a large industrial component with five pairs of tools in a double-sided incremental forming (DSIF) process and was compared with the reference computation. The results acquired with multi-tools were in good agreement with experimental and reference computation while reducing the simulation time by more than 200 %. The concept of multi-tooling, which is extensively studied in this work, can be easily implemented without adding a complex algorithm to the finite element model.

Implementation of Lead Time Improvement in the Cutting Production Process using Clustering Data Mining and Lean Manufacturing

In steel companies, there are some processes in the production such as cutting, machining and heat treatment. The production process begins with cutting process and then machining process and the last one is the heat treatment process. It becomes a background that gives the challenge and needs continuous improvement on all aspects, mainly in the cutting process. The research is conducted at one of steel companies located in Pulogadung Industrial Estate. The purpose of the research is to know the factors which cause process lead time cannot be achieved. The methods used are clustering data mining and lean manufacturing. Clustering method can be used to focus on big data and find out clusters or the same pattern. Those clusters are processed with Weka software and using K-means algorithm. Improvement ideas will be implemented to the formed clusters using lean manufacturing such as Single Minute Exchange of Dies (SMED) which have been mapped through value stream mapping, 5S, and Kanban beforehand. The materials’ dimension on the production process is affecting the cutting process lead time. The thicker material diameters will need a longer time to process. With the methods used, lead time of cutting process increased from 3449 minutes to 2165 minutes (3 days to be 2 days). Meanwhile if the “SMED” activities are implemented, the cutting process lead time increased from 187 minutes to 136 minutes.
 Keywords: Clustering; SMED; Lean Manufacturing; Process Lead Time; Value Stream Mapping

Improving lead time of pangasius fillet production process based on value stream mapping: a case study

Value stream mapping (VSM) is one of the critical tools to identify waste ful steps in the production process and help build the future VSM by applying lean production system innovations. This research aims to identify wastes in non-value-added pangasius fillet lines at GEPIMEX 404 based on lean tools. Firstly, the article explores the company’s production process, builds the current value chain map, and identifies the wastes. Then, the authors use Kanban cards to ensure quality and output, eliminating inventory of semi-finished products in the production line. Next, the authors develop a future VSM and simulate the production process using Arena software to verify the effectiveness after proposing improvements. Finally, the results showed a significant step towards reducing production time from 7.59 to 4.96 hours.

MANAJEMEN LEAN PADA LAYANAN KEMOTERAPI ANAK RAWAT INAP DI RUMAH SAKIT CIPTO MANGUNKUSUMO

Background: Cancer in children has high morbidity and mortality.
 Retinoblastoma is the most common solid tumor in children at the
 Cipta Mangunkusumo Hospital (RSCM). Chemotherapy is one of
 the therapeutic modalities, interdisciplinary and many procedures.
 Lean management continuously reduces waste and improves work flow.
 Objective: This study used lean management to determine the
 efficiency of health care in teaching hospital.
 Methods: Action research was conducted at RSCM. Sampling by purposive sampling that represents the role in the flow of the service process. The observation guide uses cycle time observation
 sheets, value-added analysis sheets, waiting time and lead time.
 The waste found is listed in the DOWNTIME matrix. Observations
 were made on inpatient chemotherapy services for children and
 then a diagnosis was made using Value Stream Mapping. The
 Kaizen team consisted of pharmacists, nurses, doctors doing a plan-do-study-action, prepared an intervention plan, and conducted
 post-intervention observations. The 5S method is used to improve
 service flow.
 Results: In this study, patients with retinoblastoma in class III in
 patient ward included were 7 patients in the pre-intervention group and 16 patients in the postintervention group. Major decreases in lead time happened in the subprocesses of ordering chemotherapy (75%), decision-making of chemotherapy administration (55%) and
 filling of the resume (41%). Lead time process in chemotherapy administration for retinoblastoma changed from 48 hours, 36 minutes
 (more than 2 days) to 38 hours, 38 minutes (1.6 days or less than
 2 days). The efficiency of the process was measured using value
 added ratio which showed changes from 33% to 37%.
 Conclusion: 
 Lean management applied in the process of chemotherapy administration in the inpatient wards increased the
 efficiency of the process.

Learning in Structured MDPs with Convex Cost Functions: Improved Regret Bounds for Inventory Management

A fundamental yet notoriously difficult problem in operations management is the periodic inventory control problem under positive lead time and lost sales. More recently, there has been interest in the problem setting where the demand distribution is not known a priori and must be learned from the observations made during the decision-making process. In “Learning in Structured MDPs with Convex Cost Functions: Improved Regret Bounds for Inventory Management,” Agrawal and Jia present a reinforcement learning algorithm that uses the observed outcomes of past decisions to implicitly learn the underlying dynamics and adaptively improve the decision-making strategy over time. They show that, compared with the best base-stock policy, their algorithm achieves an optimal regret bound in terms of the time horizon and scales linearly with the lead time of the inventory ordering process. Furthermore, they demonstrate that their approach is not restricted to the inventory problem and can be applied in an almost black box manner to more general reinforcement learning problems with convex cost functions.

Comparison of discrete time inventory systems with positive service time and lead time

This paper investigates two discrete time queueing inventory models with positive service time and lead time. Customers arrive according to a Bernoulli process and service time and lead time follow geometric distributions. The first model under discussion based on replenishment of order upto $S$ policy where as the second model is based on order placement by a fixed quantity $Q$, where $Q=S-s$, whenever the inventory level falls to $s$. We analyse this queueing systems using the matrix geometric method and derive an explicit expression for the stability condition. We obtain the steady-state behaviour of these systems and several system performance measures. The influence of various parameters on the systems performance measures and comparison on the cost analysis are also discussed through numerical example.

Investigation and implementation of VSM in water distillation plant

Value stream mapping (VSM) is a vital lean manufacturing tool accustomed to identify and reduce the process lead time and the work in process inventory for improvement of the overall efficiency of an organization. This paper aims to investigate and implement value stream mapping in water distillation plant. The data is collected from the various production processes carried out in plant after analyzing the all collected data. We had prepared the current state map and value-added activities and non-value-added activities had found. After conducting an impressive investigation on non-value-added activities, suggestions are made to minimize the process lead time and work in process inventory. The lean techniques like Kaizen, 5S are used to make necessary changes to improve the overall efficiency and after considering the proposed changes future state value stream map was drawn. After successful implementation of VSM Technique in water distillation plant the improvements are, the processing time is reduced from 171 s to 143 s and lead time is decreased from 8057 s to 6344 s.

Optimal lot-sizing policy for a failure prone production system with investment in process quality improvement and lead time variance reduction

<p style='text-indent:20px;'>To survive in today's competitive market, it is not enough to produce low-cost products but also quality-related issues and lead time needs to be considered in the decision-making process. This paper extends the previous research by developing a stochastic economic manufacturing quantity (EMQ) model for a production system which is subject to process shifts from an <i>in-control</i> state to an <i>out-of-control</i> state at any random time. Moreover, we consider the option of investment to increase the process quality and decrease the lead-time variability. Closed-form solutions of the proposed models are obtained by applying the classical optimization technique. Some lemmas and theorems are developed to determine the optimal solution of the decision variables. Numerical results are obtained for each of these models and compared with those of the basic <i>EMQ</i> model without any investment. From the numerical analysis, it has been observed that our proposed model can significantly reduce the cost of the system compared to the basic model.</p>

Perancangan Alat Pengupas Buah Durian Di UKM Pancake Lena

DABSTRACTPancake Lena is the small and medium industries that produce durian pancake. These SMEs durian pancake producing as many as 600 pieces per day. For the manufacture of pancakes per day SMBs can spend as much as 25 durian fruit. Preliminary observations on the initial durian peel using a knife, but by using this way many factors that cause accidents and long lead time process. The average time for the start of durian peel 1.1 minutes while peeling durian total with an average time of 3.3 minutes. In the observations were made for 25 pieces of durian with a work accident as much as 4 times. To solve the problem time and productivity happens to need a durian peeler. How it works peeler durian by sticking a durian on a crutch durian, then there are two claws blade left and right to stab the left side and the upper right durian, then the driver is struck so that the claw knife stab to the durian, and the left stick and right-drawn simultaneously to open a durian. The design of this durian peeler using R&D (Research and Development), which is a method of research and product development. The tool development considersefficiency, product effectivity and easeof useof product design. The efficiency of stripping time early durian fruit on average 0.11 minutes while peeling fruit durian total with an average time of 1.02 minutes and accidents reducedand productivity before and after obtained a 2,22 earned 2,27.Specifications tool designed measuring 50 cm long and 92 cm high.

Development of PLC based Sequential Pneumatic Punching System

Programmable logic sequential pneumatic system is developed for mechanical applications, like sealing, name punching, plate designing, etc. punching machine is considered as inevitable in almost all the industries like mechanical, electronic, food industries and automobile, etc. To print the hallmarks, logos as a brand. In respect to reducing the processing time by upgrading the conventional system to automation by integrating with Programmable logic control (PLC) as the system works with the interfacing of hardware (punching machine) and solenoids to control the actuation sequence. A sequential pneumatic PLC-based automatic punching machine is designed to have great control over the process of punching the hallmarks and logos with an automating feeding system followed by the punching process, which leads to a high production rate and reduces the process lead time, and increases the safety of workers.