Reducing dandori processing time using the single minute exchange of die method in swaging areas in automotive rubber components company

. The automotive component company is engaged in the manufacture of automotive rubber components. Based on data obtained from field observations, it was found that the Dandori process on the swaging Nox machine, especially TA090 type, had the highest downtime compared to another component. Based on these problems, research uses the Single Minute Exchange of Die (SMED) method to reduce Dandori downtime in the TA090 swaging process. The SMED method was carried out in three stages: 1. identify internal and external setup, 2. Converting internal to external setup, and 3. Streamlining aspects of operation. In addition, it also used data processing tools, namely SMART, fishbone, and 5W+1H as support to solve this problem. Improvements were made by converting internal work elements into external ones and streamlining aspects of operation by improving on man, method, and machine/tools categories. The result of these improvements was a decrease in downtime of 39 minutes 48 seconds and the improvement efficiency achieved was 81.2%.


Introduction
Industrial development is entering a new era where companies are required to improve their performance to be able to compete in the global market (Fathia et al., 2016).One of them is the automotive manufacturing industry which produces automotive components.The condition of business competition in the automotive manufacturing sector in the global market is getting tighter (Ibrahim et al., 2020).In 2022, world car sales will continue to increase, dominated by the Chinese market with 27 million units.Meanwhile, Indonesia itself is in 10th place for car manufacturers in 2022 (Pratama et al., 2019;Suryaprakash et al., 2020).
The Automotive component company is engaged in the manufacture of automotive rubber components.This company has 5 manufacturing plants including a mixing plant, a hose (Tango) plant, a molded (V3) plant, a Bushing Torque Rod (BTR) plant, and a Rubber Vibration Insulator (RVI) plant.Products produced include automotive components, namely torque rod assy, bush rod assy, molded rubber parts, rubber bonded with metal parts, function hoses, and rubber vibration insulator parts.Field studies conducted in the Engineering Department, this research include the development of new products and inter-departmental tooling.
The RVI plant is a place for manufacturing and assembling rubber vibration insulator parts for truck vehicles.Based on the manufacturing and assembly processes, the process at the RVI Plant uses machines such as Injection, Painting, Bonding, Wire Brush, and Press Swaging.Dandori is a term that comes from Japan, it means changing models.Manufacturing companies often encounter the term Dandori.The Dandori process starts from production planning until the product is declared to have passed production.Dies Dandori is an activity of changing the type of dies on a press machine.Based on data obtained from field observations on three swaging machines, Nox, Takoton 1 and takoton 2. It was found that the Dandori process on swaging Nox had the highest downtime compared to swaging Takoton 1 and Takoton 2, namely 2129 minutes during the last 2 months in 2022.In the swaging process of Nox, it was also found that the TA090 swaging process had higher downtime compared to another type of products, NA 140 and TA 101, namely 833 minutes.
Based on these problems, we need a proven improvement methode to reduce Dandori downtime on Swaging Nox machine, especially for TA090 type of product.
Research (Hien N. Nguyen & Nhan H. Huynh, 2019) uses Single Minute Exchange of Dies (SMED) to reduce setup time in the assembly manufacturing industry.SMED has succeeded in reducing production losses in Industry A (Fathia et al., 2016).SMED is an improvement method from Lean Manufacturing that is used to speed up setup time or production changes (Ikatrinasari et al., 2018) (Sahin & Kologlu, 2022).From one type of product to another type of product (Setiawan & Hasibuan, 2021).The goal to be achieved from implementing the SMED method is to try to speed up the setup time (Supriyati et al., 2021;Arifin, 2018).Most companies spend more than 20 percent of their production time for changeover (Azwir et al., 2021).The basic concept of SMED is to reduce machine setup time, which significantly directly reduce the batch size for parts (Setyawan, 2019).This makes manufacturing companies able to produce according to customer demand (Runtuk & Sembiring, 2021).This study aims to reduce the time in the TA090 Dandori process on swaging Nox machine using the Single Minute Exchange of Die (SMED).

Methods
Setup operations consist of two fundamentally different types of operations, namely internal setup and external setup (Nurrizky et al., 2021).Internal (Inside Exchange of Die or IED) is an activity that can only be carried out when the machine is stopped such as installing or removing dies.The second type of operation, namely external setup (Outside Exchange of Die or OED), is an activity that can be performed while the machine is operating, such as transferring old prints to storage, preparing bolts for operations and so on.The following are the basic steps and conceptual stages of the SMED method (Sousa et al., 2018;Silva et al., 2021).
This research was conducted in an automotive company on the TA090 swaging process.This was done because swaging TA090 had the highest downtime.Primary data is obtained by measuring time directly with a stopwatch.Secondary data obtained from company reports.This study uses systematic stages so as not to deviate from the target.The following stages of problem solving can be seen in Figure 1.

Defining the Problem
When carrying out the dies Dandori process at the RVI Plant, high downtime data was found, so it is necessary to secure Dandori activities.Observation time was carried out during shift 1 working hours.Data collection for Dandori processing time was carried out in line swaging.The following set-up time data can be seen in Table 1.After obtaining Dandori downtime data, the next process is to make a pareto diagram which aims to select the production line area to be repaired to reduce Dandori downtime.Figure 2 is a pareto diagram which is the basis for improvement based on the highest downtime to select the production line area to be improved.2 and Dandori data for March can be seen in Table 3.

Current Condition Analysis
Data collection of TA090 swaging Dandori time using a stopwatch tool directly taken on the nox swaging machine.Time is taken by the Dandori operator based on each work element.The following is the processing time data for Dandori work elements and the Dandori processing time can be seen in Table 4. Analysis of working conditions that occur, starts from the separation between each setup category.Dandori work elements have not been distinguished between internal and external setups.External activities are still carried out when the machine is off.There are advance activities, namely preparing tools, taking hand forklift, looking for and taking dies.

Target Analysis
The S.M.A.R.T method is used as a tool to analyze the target to be selected.The following SMART analysis results can be seen in Table 5.

Converting Internal to External Setup
This stage is carried out to find ways to change these activities into external activities.Table 6 is the change in activity from an internal setup to an external setup.

Streamlining Aspects of Operations
At this stage, the process of streamlining or improving each work process in the internal setup process is carried out.Table 7 is the result of streamlining work processes

Cause and Effect Analysis
The fishbone diagram method is used to find out the root cause of all the data that has been analyzed.Fishbone diagram is structured diagram to visualized root caused of the problem.The problem or effect is displayed at the head or mouth of the fish.Possible contributing causes are listed on the smaller "bones" under various cause categories.This diagram was filled by involving production engineering team in brainstorming activity.The analysis is carried out by considering human factors, methods, machines, materials, money and the environment.However, the analysis is carried out only by human factors, methods and machines.This was done according to the problem.Figure 3 is the root of the problem based on the Fishbone diagram.

Figure 3 Fishbone Diagram Improvement Process Planning
After obtaining the roots of the problem that occurs in the method, man, and tools factors.Then do the appropriate improvements from the root of the problem.Before carrying out these improvement, a countermeasures plan is made by answering what, why, who, when, where, and why (5W+1H) on the roots of the problem found on previous stage.Table 8 are improvements plan with 5W+1H.

Complete die replacement
There is a process of calling man power

Man power not standby
No dies type tag Irregular dies storage

Long Dandori time
No improvements There are many models in one machine Replacement of dies using hand forklift

Improvement Implementation
After the improvement plan is carried out, it is implemented.Improvements made include making tag type dies, making new model TA090 dies and changing the method of taking dies.After the implementation of improvements then obtained several changes in processing time.The following processing time after repair can be seen in Table 9. Aspects Analysis of QCDSMPE Some of the improvements that have been obtained are then analyzed for the impact of the improvements.The impact of the improvements had been discussed with the production engineering team on quality, cost, delivery, morale, productivity, and environmental aspects (QCDSMPE).The improvement results have a significant effect on the company's improvement.The following is an analysis regarding the potential impact of QCDSMPE, which can be seen in Table 10.The productivity of line swaging increased because the improvement of tools and methods using SMED reduced the Dandori processing time by 81% from 49 minutes to 10 minutes so that production results could increase.Productivity of line swaging increased by 2,496 pcs/month.

Environment
The results of improved tools and methods will make it easier for operators to carry out the Dandori process and make the work environment tidier and easier to clean Based on QCDSM Analysis and production data, productivity has the most significant effect.After improvements, productivity of line swaging increased by 2,496 pcs/month after converting 39 minutes 48 seconds of time-wasting Dandori process to profitable productive time.
Implementation of Lean Principle such as SMED by converting internal activity into external activity as well as using pneumatic power tools and other tools at forging line helps setup time reduced by 40%.The previous setup time was 90 minutes is reduced to 54 minutes (Talekar et al. 2019).

Conclution and Suggestion
Based on the problem analysis and corrective actions using the SMED method, it can be concluded that improvements in Dandori process activities can reduce Dandori time.The initial time confinement was 48 minutes 55 seconds (2935 seconds) reduce to 9 minutes 12 seconds (552 seconds).The total time is reduced by 39 minutes 48 seconds (2383 seconds) so that the production line stop time is reduced by 81.2%.The results of this study contribute to the company where company get efficient production time and reduce process losses.Further research can be carried out by linking other movements so that the production process time can be optimally reduced.

Figure 1
Figure 1 Study Framework

Figure 2
Figure 2 Dandori Downtime Pareto Diagram Based on Figure 2, it can be seen that the swaging nox production line area has the highest downtime than swaging tokoton 1 and swaging tokoton 2, which is 2129 minutes.Based on the high downtime, it is necessary to analyze the problems that occur in the Dandori process in the nox swaging line production area.Swaging Nox machine produces several types of products, namely TA090, NA140, TA101.The Dandori data that was analyzed was in February 2022 and March 2022 as Dandori data samples.The following Dandori data for February can be seen in Table2and Dandori data for March can be seen in Table3.

Table 1
Downtime Data of Dandori Plant RVI

Table 2
February Monthly Data of Dandori Time and Frequency

Table 3
March Monthly data of Dandori Time and Frequency

Table 4
Dandori Processing Time Data

Table 5
Analysis of S.M.A.R.T

Table 6
Dandori time after converting internal to external setup

Table 7
Dandory time after streamlining aspects of operations

Table 9
Process After Improvement

Table 10
Analysis of QCDSMPE Aspects