multi-floor facility layout improvement using systematic layout planning

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Multi-floor Facility Layout Improvement Using Systematic Layout Planning S.S. Hosseini 1,a , K.Y. Wong 1, b, S.A. Mirzapour 1,c and R. Ahmadi 2,d 1 Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, Skudai, Malaysia 2 Department of Industrial Engineering, Islamic Azad University of QAZVIN, Iran a [email protected], b [email protected], c [email protected], d [email protected] Keywords: Multi-floor facility layout problem, Systematic Layout Planning, Production and Operation management, Flow analysis Abstract. This study aims at improving the multi-floor layout of a card and packet production company based on the Systematic Layout Planning (SLP) method. A detailed study of the facility layout such as its operational processes, flow of materials and activity relationships has been done. Long distance, cross-traffic, and cost have been identified as the major problems of the current multi-floor layout. Three alternative layouts were suggested by SLP and the best alternative was selected and compared with the current layout. The results revealed that the new alternative layout could considerably improve the company’s layout problems. Introduction Multi-floor facilities are constructed in countries or areas with high land cost because usable land is either very limited and/or very expensive, especially as one gets closer to industrialized zones. Multi-floor layout differs from single-floor layout in terms of travelling time, distance and vertical transporting of materials. Another distinction between them is the determination of area feasibility. The limitations of available horizontal space create a need to explore vertical expansion of facilities [1]. Lee et al. [2] proposed an improved genetic algorithm to derive solutions for multi-floor facility layouts having inner structure walls and passages. Another study that considered two-floor facility layout problems with unequal departmental areas in multi-bay environments was conducted by Krishnan and Jaafari [3] . They proposed a mimetic algorithm to minimize material handling cost and to maximize closeness rating. Khaksar Haghani et al. [4] presented an integer linear programming model for designing multi-floor layouts of cellular manufacturing systems. Their objective was to minimize the total costs of intra-cell, inter-cell, and inter-floor material handling. Rapid increase of demand in production leads factories to enhance their potentials in production and effectiveness to compete against their market rivals. However, production processes must be equipped with the ability to decrease cost and increase effectiveness. In facility layout problems, minimization of total cost or total time of material handling is generally used as the objective function, which depends on distance between facilities [5]. Systematic layout planning (SLP) can be used as the facility layout improvement technique to find a sensible layout by using material flow analysis and closeness rating [6] . It has been proposed by the American plant design expert, Richard Muther in 1961 [7, 8, 9]. Wiyaratn et al. [7] applied SLP procedures to improve the plant layout of iron manufacturing and decreased the distance of material flow. Zhu and Wang [9] improved the overall layout of long yards using SLP,in which the best layout demonstrated a good process flow and practical significance.In this study, SLP procedures are applied as an improvement method in a two-floor company to suggest better alternative layouts . The new improved layout will provide a reduction of distance, cost and cross- traffic to have an efficient production layout. Advanced Materials Research Vol. 845 (2014) pp 532-537 Online available since 2013/Dec/04 at www.scientific.net © (2014) Trans Tech Publications, Switzerland doi:10.4028/www.scientific.net/AMR.845.532 All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TTP, www.ttp.net. (ID: 128.193.164.203, Oregon State University, CORVALLIS, United States of America-29/06/14,13:22:04)

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Multi-floor Facility Layout Improvement Using Systematic Layout Planning

S.S. Hosseini1,a, K.Y. Wong1, b, S.A. Mirzapour1,c and R. Ahmadi2,d

1 Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, Skudai, Malaysia

2 Department of Industrial Engineering, Islamic Azad University of QAZVIN, Iran

[email protected], [email protected], [email protected], [email protected]

Keywords: Multi-floor facility layout problem, Systematic Layout Planning, Production and Operation management, Flow analysis

Abstract. This study aims at improving the multi-floor layout of a card and packet production company based on the Systematic Layout Planning (SLP) method. A detailed study of the facility layout such as its operational processes, flow of materials and activity relationships has been done. Long distance, cross-traffic, and cost have been identified as the major problems of the current multi-floor layout. Three alternative layouts were suggested by SLP and the best alternative was selected and compared with the current layout. The results revealed that the new alternative layout could considerably improve the company’s layout problems.

Introduction

Multi-floor facilities are constructed in countries or areas with high land cost because usable land is either very limited and/or very expensive, especially as one gets closer to industrialized zones. Multi-floor layout differs from single-floor layout in terms of travelling time, distance and vertical transporting of materials. Another distinction between them is the determination of area feasibility. The limitations of available horizontal space create a need to explore vertical expansion of facilities [1]. Lee et al. [2] proposed an improved genetic algorithm to derive solutions for multi-floor facility layouts having inner structure walls and passages.

Another study that considered two-floor facility layout problems with unequal departmental areas in multi-bay environments was conducted by Krishnan and Jaafari [3] . They proposed a mimetic algorithm to minimize material handling cost and to maximize closeness rating. Khaksar Haghani et al. [4] presented an integer linear programming model for designing multi-floor layouts of cellular manufacturing systems. Their objective was to minimize the total costs of intra-cell, inter-cell, and inter-floor material handling. Rapid increase of demand in production leads factories to enhance their potentials in production and effectiveness to compete against their market rivals. However, production processes must be equipped with the ability to decrease cost and increase effectiveness. In facility layout problems, minimization of total cost or total time of material handling is generally used as the objective function, which depends on distance between facilities [5]. Systematic layout planning (SLP) can be used as the facility layout improvement technique to find a sensible layout by using material flow analysis and closeness rating [6] . It has been proposed by the American plant design expert, Richard Muther in 1961 [7, 8, 9]. Wiyaratn et al. [7] applied SLP procedures to improve the plant layout of iron manufacturing and decreased the distance of material flow. Zhu and Wang [9] improved the overall layout of long yards using SLP,in which the best layout demonstrated a good process flow and practical significance.In this study, SLP procedures are applied as an improvement method in a two-floor company to suggest better alternative layouts . The new improved layout will provide a reduction of distance, cost and cross-traffic to have an efficient production layout.

Advanced Materials Research Vol. 845 (2014) pp 532-537Online available since 2013/Dec/04 at www.scientific.net© (2014) Trans Tech Publications, Switzerlanddoi:10.4028/www.scientific.net/AMR.845.532

All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TTP,www.ttp.net. (ID: 128.193.164.203, Oregon State University, CORVALLIS, United States of America-29/06/14,13:22:04)

Systematic Layout Planning

SLP is a proven tool in providing layout design guidelines which are applied to create layout alternatives. There are 11 steps which are needed for SLP: It begins with PQRST analysis (step 1) for the overall production activities. The data collection fields including P (Product), Q (Quality), R (Routing), S (Supporting), and T (Time) should be considered to ensure the validity of input data. In steps 2 and 3, all material flows in the whole production area are collected into a from-to-chart and relationships between departments are depicted in an activity relationship chart. The step of “relationship diagram” (step 4) positions each department spatially. The steps of “space requirements” and “space available” (steps 5 and 6) determine the amount of floor space to be allocated to each department. In the “space relationship diagram” step (step 7), all the information about the size of departments from step 5 will be added into the relationship diagram. Additional design constraints and limitations are considered in steps 8 and 9. Developing layout alternatives as design candidates will be carried out in step 10. In the final step, the best design will be selected from these design candidates.

Fig1. SLP procedure [10]

Analysis of the Original Facility Layout

A card and packet production company located in Iran was selected as a case study. The production in this company operates on two floors, ground floor and first floor which produce three different types of cards and packets. The scope of this study is focused on the production operation of the company in which its total production is according to customers’order. This company has designed its plant layout based on process layout. The input of each product is equal to 800 papers and the size of each paper which is sent to the company as a raw material is 1 m2 in which each paper can produce 4 cards. This company has 20 departments and each has a different task. All these departments are labeled in Table 1. Figure 2 demonstrates the operation process chart showing the chronological sequence of production. From-to-chart analysis for distance and material flow is done to show the relationships between departments in each process. Table 2 presents the total travelling distance and closeness rating between departments where distance is calculated using the rectilinear method.

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Table1. Label of departments

Label Department Label Department Label Department Label Department

A Raw paper storage 1

G Product 2 Boxing M Packaging S Raw paper storage 2

C Press room H Product 3 Imprinting

N Trash storage T Product storage (packets)

D Cutting 1 I Gold embossing process

O Cutting 2 U Maintenance room

E Product 1 imprinting

J Product 3 boxing Q Final Product storage (card and packet)

V Packet assembly

F Product 2 imprinting

L Card and Packet inspecting

R Product 1 boxing X Entrance

Fig2. Flow Process Chart

Table 2.Total travelling distance and closeness rating

Departments Distance

(m) Closeness

Rating Departments

Distance (m)

Closeness Rating

Departments Distance

(m) Closeness

Rating

A - C 272 I F - G 474.5 E J - N 152 I

A - X 618 E G - U 265 I J - L 2835 A

C - D 344 I G - T 860.75 A L - R 1650 A

C - U 297 I G - N 188 I L - N 117 I

C - X 85.75 I G - L 3430 A L - M 665 E

D - E 514.5 E G - I 864 A M - U 499 E

D - F 745.5 E H - U 436 E M - Q 8417.5 A

D - H 1008 A N - R 122 I O - V 464 I

D - N 552.5 E H - N 93.75 I O - U 88 E

D - U 340 I H - J 445.25 E O - S 147.2 I

E - U 375 E H- I 455 E R - U 329 I

E - R 162.5 I I - U 383 E R - T 1036.8 A

E - N 129 I I - R 434 E S - X 112.2 I

E - I 812 E I - N 96 I T - V 688 E

F - U 411 E I - J 621 E U - V 138 I

F - N 114 I J - U 299 I Total 35184.95

F - I 644 E J - T 954.25 A

534 Materials, Industrial, and Manufacturing Engineering Research Advances 1.1

Based on these data, the relationship of each activity is depicted in Figure 3. The closeness values are defined as A =absolutely important, E = especially important, I = important, O= ordinary closeness, and U= unimportant. As mentioned before, in addition to the high total travelling distance problem, material flows of this company present some cross-traffics in the major material pathway especially between the departments that are located on the first floor. As can be observed in Figure 4, there are 38 cross-traffics on this floor, and this has resulted in a poorer movement of materials.

Fig3. Relationship diagram Fig4. The cross-traffic of existing facility layout

A majority of departments that exist in the company are made from partitions, so the rearrangement cost is not very expensive. Except two or three, all the machines that are located in each department are portable. The location of elevator between these two floors is fixed and this is the only way for products to be transported between the floors. Moreover, departments P and W are fixed departments which are not involved in the production process but their areas or sizes will be considered. The space required for each department is shown in Table3.

Table3. Space requirement information

Department Area

(m2)

Department Area

(m2)

Department Area

(m2)

A 80 I 36 Q 128 C 48 J 56 R 56 D 78 L 120 S 83 E 80 M 60 T 90 F 30 N 35 U 70 G 72.25 O 25 V 80 H 45.5 P 450 W 42

Developing Layout Alternatives

Regarding the analysis of the production operation, it is found that the long distance and number of cross-traffics could be reduced. The closeness values between activities are rearranged from the most important one to the least important one, following the activity relationship chart. According to the SLP method, the alternative facility layouts are developed. The current and three alternative layouts are displayed in Fig. 5, 6, 7 and 8 respectively.

Fig5. Current Layout Fig 6.Layout Design I

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Fig 7.Layout Design II Fig 8.Layout Design III

Evaluation

As can be demonstrated in Table 4, layout design 1 gives the highest improvement compared to other alternatives. The total travelling distance has been decreased from 35184.95m to 26244.2m or about 25.41% improvement. The number of cross-traffics in layout design 1 is reduced to 24 which represent 36.84% improvement in comparison to the current layout. The estimation of cost reduction begins with the calculation of the travelling cost per one meter unit. The average of payment per one worker is equal to 11 dollars per shift and the total working time per shift is 480 minutes (8 hours × 60 min per hour) so the cost of one worker per minute is 0.023 dollars per minute.

The travelling time per distance of a worker is obtained by estimation. It is estimated that a worker will move at about 20 m/minute from one point to another. As a result, the travelling cost per meter unit is obtained by multiplying the cost of one worker per minute with the inverse of the worker’s moving speed.

Travellingcostpermeter = $0.023 min × 1min 20m = $0.00115 m⁄

The estimated cost for each layout alternative is obtained by multiplying the distance travelled for each layout with the cost coefficient gained from the previous calculation. As can be seen in Table 4, layout design 1 saves more money than other layouts; it has been declined from $40.46 to $30.18. The improvement in total travelling cost is about 25.41 % that indicates the company can save up to $10.28 per day.

Table 4. Comparison between alternatives and current layout

Total travelling

Distance (m)

Cross-

traffic

Total travelling

cost ($)

Current

Layout 35184.95 38 40.46

Layout

Design 1 26244.20 24 30.18

Layout

Design 2 29084.15 30 33.45

Layout

Design 3 29978.15 27 34.47

Conclusion

In this paper, SLP procedures are applied to analyze and rearrange the production layout of a card and packet production company. High total travelling distance, cross-traffic and cost are identified as the major layout problems of this company. SLP is used as an analysis and synthesis tool to generate three different layout alternatives. Based on the results generated, the alternative which has

536 Materials, Industrial, and Manufacturing Engineering Research Advances 1.1

the most significant improvement in performance measures is selected. Layout design 1 is suggested to the company because besides saving greater traveling cost, it has the lowest total travelling distance and number of cross-traffics.

References

[1] Bozer, Y. A., Meller, R. D., and Erlebacher, S. J., “An improvement-type layout algorithm or single and multi-floor facilities”. Management Science, 40(7): 918- 932, 1994 [2] Lee, K., Roh, M., and Jeong, H. “An improved genetic algorithm for multi-floor facility layout problems having inner structure walls and passages”. Computers & Operations Research, 32:879–899, 2005. [3] Krishnan, K. K., and Jaafari, A. A., “A mixed integer programming formulation for multi floor layout”, African Journal of Business Management, 3: 616-620, 2009. [4] Khaksar-Haghani, F., Kia, R., Mahdavi, I., Javadian, N., and Kazemi, M., "Multi-floor layout design of cellular manufacturing systems." International Journal of Management Science and Engineering Management 6, no. 5: 356-365, 2011. [5] Kohara, D., and Yamamoto, H., “Efficient Algorithms Based on Branch and Bound Methods for

Multi Floor Facility Layout Problems”, Proceedings of The 9th Asia Pasific Industrial Engineering

& Management Systems Conference, Bali-Indonesia: 387-395, 2008.

[6] MA, C. P., and YAN, Z. G. "Analysis and Optimization of Assembly Workshop System Based on SLP, J." Logistics Engineering and Management, pp.31, 46-49, 2009. [7] Wiyaratn, W., and Watanapa, A., "Improvement Plant Layout Using Systematic Layout Planning (SLP) for Increased Productivity." World Academy of Science, Engineering and Technology 72, vol.36, pp. 269-273, 2010. [8] W Wiyaratn, W., Watanapa, A., and Kajondecha, P., “Improvement Plant Layout Based on

Systematic Layout Planning” IACSIT International Journal of Engineering and Technology, Vol. 5,

No.1: 76-79, 2013.

[9] Yujie, Z., and Fang, W., "Study on the General Plane of Log Yards Based on Systematic Layout Planning." In Information Management, Innovation Management and Industrial Engineering, 2009 International Conference on, vol. 3, pp. 92-95. IEEE, 2009. [10] Tompkins, J. A., White, J. A., Bozer, Y. A., and Tanchoco, J. M. A., “Facilities planning”, 4th edition, Hoboken: John Wiley, 2010

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Materials, Industrial, and Manufacturing Engineering Research Advances 1.1 10.4028/www.scientific.net/AMR.845 Multi-Floor Facility Layout Improvement Using Systematic Layout Planning 10.4028/www.scientific.net/AMR.845.532