ORIGINAL ARTICLE Implementing lean manufacturing with cellular layout: a case study L. N. Pattanaik & B. P. Sharma Received: 29 March 2007 / Accepted: 19 June 2008 / Published online: 19 August 2008 # Springer-Verlag London Limited 2008 Abstract Lean manufacturing is an applied methodology of scientific, objective techniques that cause work tasks in a process to be performed with a minimum of non-value adding activities resulting in greatly reduced wait time, queue time, move time, administrative time, and other delays. In a cellular manufacturing system (CMS), machines are grouped into several cells, where each cell is dedicated to a particular part family and the objective is to maximize cell independence. CMS helps in reducing the material handling, work-in-process, setup time, and manufacturing lead time and improve productivity, operation control, etc. The facility layout used during lean implementation can be either be a line layout or in the form of cells. After grouping parts in to various part families, machine cells can be formed to produce those parts well inside the cells. As some of the lean manufacturing concepts are different from that of cellular manufacturing, e.g., establishment of Takt time, Takt-based resource balancing, etc., some new cell design methodology is required to be explored that is compatible with lean manufacturing. The rate at which work progresses through the factory is called flow rate or Takt. In the present work, a design methodology for cellular layout is proposed for implementing lean concepts and is exemplified in a manufac- turing industry dealing with ammunition components for defense applications. Based on Takt time for various parts, the production flow among cells was optimized thus minimizing several non-value added activities/times such as bottlenecking time, waiting time, material handling time, etc. This case study can be useful in developing a more generic approach to design cellular layouts in lean environment. Keywords Lean manufacturing . Cell formation . Takt time . Value adding and non-value adding activities . Value stream mapping 1 Introduction Lean manufacturing (LM) has increasingly been applied by leading manufacturing companies throughout the world, led by the major automobile manufactures and their equipment suppliers. A core concept of LM is pull production in which the flow on the factory floor is driven by demand from downstream pulling production upstream as opposed to traditional batch-based produc- tion in which production is pushed from upstream to downstream based on a production schedule. In a recent survey, approximately 36% of US-based manufacturing companies have implemented lean or are in the process of implementing lean. Some of the changes required by LM can be disruptive if not implemented correctly and some aspects of it are not appropriate for all companies [2]. An LM facility is capable of producing product in only the sum of its value added work content time. Features of a typical LM model include: one unit at a time production; non-value added time eliminated; production in the work content time only; relocation of required resources to the point of usage; and all processes balanced to produce at same Takt rate. The rate at which work progresses through the shop floor is called Takt. It is a time–volume relationship calculated as the rhythm, beat, or cadence for each process of a flow line and used to establish resource definition and line balance. The flow of the product is achieved by causing all of its work tasks to be grouped and balanced to a calculated Takt time. Cellular manufacturing (CM) is an application of group technology, a manufacturing philosophy in which parts are Int J Adv Manuf Technol (2009) 42:772–779 DOI 10.1007/s00170-008-1629-8 L. N. Pattanaik (*) : B. P. Sharma Department of Production Engineering, Birla Institute of Technology, Mesra, Ranchi, Jharkhand 835 215, India e-mail: lnpattanaik@yahoo.com