Lean manufacturing is a production system, which was first developed by Toyota Production Systems (TPSs) to reduce wastes while improving the operational and environmental performance of manufacturing and industrial businesses. While the global industrial market suffers from gnarled competition, lean manufacturing philosophy is providing an effective methodology to reduce cost and maximize profit. In addition, the market no longer accepts waste caused by out of control production or inefficient processes. A commitment to quality and lean operations will result in quality improvement, waste elimination and reduction in time and costs. Value stream mappings (VSMs), a lean manufacturing tool, which originated from the Toyota Production Systems (TPSs), is known as “material and information flow mapping.” This mapping tool uses the techniques of lean manufacturing to analyze and evaluate certain work processes in a manufacturing operation. This tool is used primarily to identify, demonstrate and decrease waste, as well as create flow in the manufacturing process. VSM can be created merely using paper and pencil; however, more advanced maps are created using Microsoft Visio as well as Microsoft Excel. This paper describes practical implementation strategies for using lean manufacturing and an industrial case study (Cement Sacks Factory) is included. After lean manufacturing methodology has been applied to the case, results are produced as Cement Sacks Factory process efficiency is raised by 4.31% and the TAKT time is reduced about 56%.

A production line is an important class of manufacturing system when large quantities of identical or similar products are to be produced. The performance of a production line is highly influenced by machine failures. When a machine fails, it is then be unavailable during a certain amount of time required to repair it. Analysis of production lines divides into three types: analytical, approximation and simulation models. The analytical and approximation models have assumptions which make these models unrealistic such as reliable workstations, certain processing distribution, the first workstation cannot be starved and the last workstation cannot be blocked. The main problems in production lines treatment are the calculation of throughput and average levels of buffers because of the great size of state space. An analytical model is reviewed to clarify the limitations to use such treatment in real production lines. Simulation modeling of production lines is considered very important for designers interested in: Workload Allocation Problem (WAP), Server Allocation Problem (SAP), and Buffer Allocation Problem (BAP). This paper studies and analyzes the performance keys, which effect on production lines. A simulation model is developed by using ARENA software and used to analyze and test several bottlenecks that are causing severe congestions in different areas on the production line and could resolve all of these bottlenecks. In this paper, an actual cement production line is studied. After a simulation time of 13 days, a simulation results show the line bottlenecks, workstations utilization, buffer capacities and the line production rate. The outputs clarify redesign of allocation of buffers, which verify an optimum size could be made; it might be taken into consideration when designers implement such lines. Finally modified better workstations utilization, buffer capacities and the line production rate with an increase about 15% of the production rate and economizing of 37 % from buffer capacities.