Home

Search

Collections

Journals

About

Contact us

My IOPscience

Productivity improvement using industrial engineering tools

This content has been downloaded from IOPscience. Please scroll down to see the full text. 2012 IOP Conf. Ser.: Mater. Sci. Eng. 36 012006 (http://iopscience.iop.org/1757-899X/36/1/012006) View the table of contents for this issue, or go to the journal homepage for more

Download details: IP Address: 121.96.255.145 This content was downloaded on 06/08/2014 at 08:45

Please note that terms and conditions apply.

1st International Conference on Mechanical Engineering Research 2011 (ICMER2011) IOP Publishing IOP Conf. Series: Materials Science and Engineering 36 (2012) 012006 doi:10.1088/1757-899X/36/1/012006

Productivity improvement using industrial engineering tools
H.A. Salaam1, S. B. How, M. F. Faisae
Faculty of Mechanical Engineering, Universiti Malaysia Pahang (UMP), Pekan, Pahang Darul Makmur, 26600, Malaysia E-mail: hadisalaam@ump.edu.my
Abstract. Minimizing the number of defects is important to any company since it influence their outputs and profits. The aim of this paper is to study the implementation of industrial engineering tools in a manufacturing recycle paper box company. This study starts with reading the standard operation procedures and analyzing the process flow to get the whole idea on how to manufacture paper box. At the same time, observations at the production line were made to identify problem occurs in the production line. By using check sheet, the defect data from each station were collected and have been analyzed using Pareto Chart. From the chart, it is found that glue workstation shows the highest number of defects. Based on observation at the glue workstation, the existing method used to glue the box was inappropriate because the operator used a lot of glue. Then, by using cause and effect diagram, the root cause of the problem was identified and solutions to overcome the problem were proposed. There are three suggestions proposed to overcome this problem. Cost reduction for each solution was calculated and the best solution is using three hair drier to dry the sticky glue which produce only 6.4 defects in an hour with cost of RM 0.0224. Keywords: Industrial engineering tools, Check sheet, Pareto chart and Cause and effect diagram.

1. Introduction Survival of any industry in today’s environment especially manufacturing industry not only depends on response time but also quality of the product produced. In this respect, seven quality control tools can be utilized as a method or process to reduce the manufacturing costs, production time and increasing the production line productivity. Productivity can be defined as a ratio between output and input. Productivity improvement is a critical success factor and the foundation of profitability [1]. Productivity measurement is a long-term measurement. Any changes in dynamic potential show a growth or reduction of figures over a long period [2]. Industrial Engineering in the other hand concerned with the design, improvement, and installation of the integrated system of men, materials, and equipment. It draws upon specialized knowledge and skills in the mathematical, physical, and social sciences, together with the principles and methods of engineering analysis and design, to specify, predict and evaluate the result to be obtained from such a system [3]. Today, quality plays an important role as it leads to increasing number of product sold and also increment of company profit. Productivity, quality, and cost of operation relatively depended to each other. By improving the productivity, the quality also must be improved and hence lower the reject rates or defects [4].

___________________________ 1 Corresponding author: H. A Salaam Email address: hadisalaam@ump.edu.my

Published under licence by IOP Publishing Ltd

1

1st International Conference on Mechanical Engineering Research 2011 (ICMER2011) IOP Publishing IOP Conf. Series: Materials Science and Engineering 36 (2012) 012006 doi:10.1088/1757-899X/36/1/012006

Engineer needs to know what the main problem is, the causes of the problem before they proposed any solutions. However, logical and systematic method should be applied to make the job easier by locating and eliminating the root cause of the problem. There are many techniques [5] available in problem solving, ranging from simple and easy to use methods to relatively complicate and advance statistical tools [6]. The Seven QC Tools are easier to apply and understand and yet proven scientific management tools. It can be used in all process phases, starting from the beginning of a product development up to management of a process, on day to day basis and in systematic manner [7]. They form the fundamental foundation for all problem solving and quality control activities. Generally, the Seven QC tools are check sheet, Pareto chart, flowchart, cause and effect diagram, histogram, scatter diagram and control chart [8] and [9]. These tools are also known as Total Quality Management (TQM) tools [10]. Many researches have been done using seven quality control tools. Pierchala and Jyoti Surti [11] and Winco [6] used Statistical Process Control to solve problems their case study. Jafri and Chan [4] presents a case study in plastic injection molding company deployed check sheets, pareto chart, cause and effect diagram and control chart to improve the monthly defect quality from 13.49% to 7.4%. Naser [12] used histogram, scatter plot and pie chart to investigate their case study.

2. Methodology This study starts with identifying suitable company to do this project. The main criteria used to select a company are small medium enterprise (SME). This is because SME companies did not have enough capital to hire expertise to help them to improve their production line productivity, quality of the product produced and at the same time reduce the number of defect products. The company that has been chooses is a paper box producer company located in Kuantan, Pahang. Next, a few visits were organized to the company to study their production line layout, product process flows and the number of defects produced in each production line. Based on observation and discussions with the company representative, the selected line is the one which produce 1040 mm box. This is because it has the highest demand from customer, daily produced and at the same time it produces many defects. During the visits, observations at the production line were done to see how the operators perform their job at the production line. Besides that, interview with operators were organized to get the feedback and also defect product data were collected and analyzed using Pareto Chart. Next, cause and effect diagram were used to identify the root cause of the defect problems and proposed four solutions to overcome the problem. Manufacturing cost calculation analysis was done before select the best solution to be implemented at the company.

3. Results and discussions Based on the observation in the production line, interview with operators and supervisor and also data collection results, it was found that the production line produce 1040 mm paper box record the highest number of defects at glue workstation. It recorded 23 defects follows by slitter and partition workstations with 7 and 6 defects respectively as shown in Table 1. When Pareto Chart was plotted in Figure 1, it shows that the glue workstation has the highest frequency of defect with 23 defects or 46% of the defects that occurs on the whole process. Results from both Table 1 and Figure 1 shows that there is a problem occurs at the glue workstation.

2

1st International Conference on Mechanical Engineering Research 2011 (ICMER2011) IOP Publishing IOP Conf. Series: Materials Science and Engineering 36 (2012) 012006 doi:10.1088/1757-899X/36/1/012006

Table 1. Number of defect occurs at each Workstation. Defect Glue Partition Stitching Slitter Print Slotter Die Cut Tie Pallet 3rd //// / / // / / / / // / 5th //// / // //// / Frequency 23 6 3 7 2 2 4 3

1st //// //

2nd /// // //

4th //// / /

/

Figure 1. Pareto chart for defect occurs at each workstation. From the Figure 1; we can see that glue workstation has the highest number of defects which can cause the company unable to meet the customer demand. At the same time, company daily output drop due to the error occurs in glue workstation. Hence improvement should be done at glue workstation to minimize the error. Next, root cause analysis is done by using cause and effect analysis (fish bone) diagram. It is divided into 4 main categories; Man, Machine, Method and Material. Since the workstation is manually operated, there is no analysis for machine. Feedback from operator during the interview shows that the box paper usually sticks one to another due to stacking the box paper immediately before the glue dried. Besides that, lack of rolling and pouring glue skills on the board is one of the root causes of this problem. Another problem is that, some of the operators were tired due to long working hour since they need to do overtime to fulfill the customer demand. When looking at the method used in this workstation, the current stacking method that they used is not sufficient enough. After finish rolling the glue at the paper board, they stack it immediately before it dried. Besides that, the way they used to roll the roller in the glue tray is not sufficient because the operator arm wrist can injured easily caused by wrong position of body posture and at the same time doing repetitive work again and again. Some of the operator did not roll the roller first in the tray to minimize the glue quantity that will be rolled at the paper box. This leads to using an excessive of glue and it will take a longer time to dry. When looking at the material side, the design of the box paper and material used to make the box can be improved to minimize the assembly time and manufacturing costs. Besides that, the type of
3

1st International Conference on Mechanical Engineering Research 2011 (ICMER2011) IOP Publishing IOP Conf. Series: Materials Science and Engineering 36 (2012) 012006 doi:10.1088/1757-899X/36/1/012006

glue used can be change to more environmental friendly and odourless glue which do not harm the operator. The summary of the root cause problem for glue workstation are shown in Figure 2.

Figure 2. Summary of root cause analysis of glue workstation. To solve this problem, there are three solutions have been proposed in this project. They are divided into three solutions. The first solution is divided the paper box into three groups before stacking up, followed by the usage of electric fan or airy place for glue workstation, and the third solution is to use table lamp or hair dryer to dried out the glue. The existing method shows that the defects occurs on glue workstation is due to the glue not dry in time and at the same time the operator straight away stacked the paper box on top of it and it caused the new paper box to stick together. Hence the alternative way to solve this problem is to propose not to stack the glued paper box together but divide it into three groups such in Figure 3. For an example, when the paper box is glued, the 1st paper box is place at the slot A while the 2nd paper box is place at slot B and the 3rd paper box placed at the C slot. Hence, the paper box got more time to expose to the air and the possibility to dry is much higher than just place the paper box at a place in a time.

Figure 3. Grouping paper box into three groups. Standing fan can be used by placing it in front of the paper box after it is glued. By switching on the fan, the wind that blows to the paper box can let the glue dry. Besides using the fan to dry out the

4

1st International Conference on Mechanical Engineering Research 2011 (ICMER2011) IOP Publishing IOP Conf. Series: Materials Science and Engineering 36 (2012) 012006 doi:10.1088/1757-899X/36/1/012006

glue at the paper box, the glue workstation can be relocate to an open area which has a good air circulation to make sure the paper box is dry. However, there is a concern where the wind that blows might be too strong and blow away the entire paper box. Hence, a weight need to place on top of the paper box to make sure it will not fly away. Besides that, a small table lamp or hair dryer can be use to dry the glue. The heat transfer concept is applied where the heat of the lamp or hair dryer will dried out the paper box. Paper box can be place under the lamp or hair dryer and the air is blowing for a few seconds before stacked the paper box at semi-finish place. However, the table lamp that can be used is limited to the table lamp with long bulb. This is because the round bulb can only heat a small portion of the paper box while long bulb can heat longer portion of the paper box and reduce the production time. A few trials were conducted to see the performance of the proposed solutions. After perform a trial for a few days, number of defect products was collected and the defect cost was calculated. The summary of the results are shown in Table 2. Here, we can see that the current glue workstation produce average of 123 defects, followed by table fan 100 defects and standing fan 91.2 defects, 3 table lamps 86 defects and lastly, by using three hair dryer 6.4 defects. By looking at the results, it shows a tremendous decreasing which is good for the company. This is due to the new arrangement of standard operation procedures to reduce the amount of glue used and give extra time to let the glue dry before stacking it. Next, when we looked at the cost of defect per hour, the highest defects cost is the existing glue workstation which record RM 0.403932. Table fan is in the second place with RM 0.33283 and Standing fan in the third place with RM 0.3045533. Fourth place is 3 Table lamps with RM 0.2833786 and the last place which records the lowest defect costs is 3 hair dryers with RM 0.0224365. Based on the results, it is shown that by using 3 hair dryers, the number of defects can be reduce dramatically due to the usage of hair dryer to dry the glue. Besides that, the arrangement of the ready paper box with glue give an interval time to allow the glue to dry. Table 2. Summary of experiment results between the existing workstation and proposed solutions. Method Existing Glue Workstation 3 Table Lamp Table Fan Standing Fan 3 Hair Dryer 1 120 99 120 105 10 2 145 90 101 99 8 Trial 3 140 85 105 93 4 4 100 80 94 87 5 5 110 76 80 72 5 Average 123 86 100 91.2 6.4 Total Defect Costs (RM) / hour 0.403932 0.2833786 0.33283 0.3045533 0.0224365

4. Conclusions
This paper describes about the using of industrial engineering tools to reduce number of defects and at the same time increase production line productivity. Form the experiment that have been done, the main objective to reduce number of defects product has been achieved. From all four options that have been proposed, it is found that the best solution is using three hair dryer which record 6.4 defects in one hour or total defects costs of RM 0.0224.

5

1st International Conference on Mechanical Engineering Research 2011 (ICMER2011) IOP Publishing IOP Conf. Series: Materials Science and Engineering 36 (2012) 012006 doi:10.1088/1757-899X/36/1/012006

References [1] Kapyla J, Jaaskelainen A and Lonnqvist A 2009 Identifying future challenges for productivity research: evidence from Finland International Journal of Productivity and Performance Management. . 59(7): 607-623 [2] Heap J, 2007 Stormy productivity ahead? International Journal of Productivity and Performance Management. 56(2): 170-177 [3] Lo V H Y and Sculli D 1995 Industrial Engineering and TQM Training for Quality. 3(3): 4-7 [4] Jafri M R and Chan K T 2001 Improving Quality with Basic Statistical Process Control (SPC) Tools: A Case Study Jurnal Teknologi. 35(A): 21-34 [5] Reed, D. 1992 TQC Tools in Review, New Jersey: Printed Circuit Fabrication [6] Winco K C Y 1996 An Integrated Model for Manufacturing Process Improvement. Journal of Materials Processing Technology 61: 39-43 [7] Paliska G, Pavletic D, Sokovic M 2007 Quality tools – Systematic use in Process Industry. Journal of Achievements in Materials and Manufacturing Engineering. 25(1): 79-82 [8] Ishikawa K 1985 What is Total Quality Control. Prentice Hall. Eaglewood Cliff, N.J [9] Pimblott J G 1990 Managing Improvement – Where to start, Quality Forum. The TQM Magazine. 16: 165-173 [10] Jay H and Barry R 2008 Principles of Operations Management. 7th ed. New Jersey: Pearson Prentice Hall, Inc [11] Pierchala C E, and Jyoti S B S 1999 Control Charts as a Tool in Data Quality Improvement. Technical Report Washington: NHTSA/ DOT HS 809 005 [12] Naser A A 2007 Application of quality tools by the Saudi food industry The TQM Magazine. 19(2): 150-161

6