Volume 5 , Number 1, February.2011 ISSN 1995-6665 JJMIE Pages 9 - 16 Jordan Journal of Mechanical and Industrial Engineering Jig Design, Assembly Line Design and Work Station Design and their Effect to Productivity Adi Saptari, Wong Soon Lai, Mohd. Rizal Salleh Faculty of Manufacturing Engineering Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, Ayer Keroh, 76100 Melaka, Malaysia ___________________________________________________________________________ Abstract This report discussed the effect of workstation design, assembly design, jig design and working posture on the assembly of plugs. Two different designs of jig (vertical and rectangular) and two sets of assembly line design (one and two operators) and two set of workstations design (sitting and standing) were studied to observe their effects to productivity. Design of Experiments 2 3 with two levels of each factor is used to conduct an experiment for obtaining the most productive jig and assembly line design. Two groups of workers were employed to assemble the plug in 8 different ways. Number of replication is 32 for each setting and total of electric plugs produced by each group is 256 units. The results shows that jig design have the most significant effect to the assembly time. Furthermore, the other factors: assembly design and workstation design are also show significant factors to assembly time. However, interaction combinations of two or three factors were not significant to assembly time. The most productive assembly line design which achieved the lowest assembly time is the combination of one operator, with rectangular jig and work station design sitting. Meanwhile the working posture of workstation design that provides the lowest RULA score was sitting position, it provided score 2 which is safe. © 2011 Jordan Journal of Mechanical and Industrial Engineering. All rights reserved Keywords: Jig design, design of assembly, workstation design, productivity, working posture. ___________________________________________________________________________ 1. Introduction An assembly line is designed by determining the sequences of operations to manufacture of components as well as the final product. Each movement of material is made as simple and short as possible, with no cross flow or backtracking. All operations performed along the line are balanced. Design of assembly line plays the important role in manufacturing which will directly influence its productivity. Previous researchers [13], [19-20] explained assembly line is a widely used in production systems. The main objective of assembly lines designers is to increase the efficiency of the line by maximizing the ratio between throughput and costs. Chow [5] stated that “A simple process design criterion is to balance the assembly line so that each operation takes approximately the same amount of time. A balanced line often means better resource utilization and consequently lower production cost.” Jig is a special tool used for locating and firmly holding work piece in the proper position during the manufacturing or assembly operation. It also guides the tool or work piece during the operation. Jig is designed to increase the productivity of operation assisting worker to do job easier, faster and more comfortable. Meanwhile, applying principles of ergonomics in the job environments such as improving working posture and workstation design as part of ergonomics efforts on enhance productivity and safe working condition have been extensively discussed by many authors [7] [8] [2] [22]. The studies discussed ergonomics intervention may improve productivity, quality, operators’ working condition, occupational health and safety (OHS), and even cost effectiveness. The areas of working environment studied include workplace layouts, working tables and chairs of appropriate height, fixing hand-tools, better lighting and job rotation and also working postures. This research studied several parameters afore mentioned: i.e. design of workstation, design of assembly process, design of jig, their effects to productivity in the assembly line of plugs. Other variables such as equipment and skill of worker which may contribute to productivity are assumed kept constant. The hypothesis to be tested that either one or more of the parameters or combinations of parameters contribute to better production performance in this case assembly time or cycle time. Two designs of jig were introduced, one has rectangular shape and the other has line or vertical shape or vertical orientation. Two design of assembly were tested one with single operator and the other with two operators. Design of workstation was created by applying common industrial practices in assembly line i.e. standing or sitting position. For working poster assessment, RULA (Rapid Upper Limb Assessment) analysis was conducted to examine different workstation designs effect to safe working postures. 2. Methods 2.1 Product Design For the purpose of this experiment an electric product was chosen as a case. This product was selected since it