The lean to green evolution
Picture source: http://www.enterprisetech.com/
INDUSTRIAL ENGINEER – VOLUME 42, NUMBER 6
BY J. T. BLACK AND DON T. PHILLIPS
The lean green industrial engineer is a traditional industrial engineer armed with lean analysis tools to design and redesign systems, eliminate waste, vigorously attack and reduce variance and adopt a lean thinking mentality. The modern industrial engineer now faces an entirely new perspective on how to create socially acceptable and environmentally renewable product. Toyota Production System (TPS)-which was invented by Taiichi Ohno, Toyota’s vice president for manufacturing-now called the lean production system because of its success in America has been implemented in various forms by many companies. Companies who are using this system have been increased from 56% in 2008 to 61% in 2009.
Toyota knew it had to train a new breed of workers and educate potential suppliers about how its system differed from the American mass production system. The manufacturing and assembly cells are designed for flexibility which can handle changes in product design and customer demand. Capacity in the linked-cell-manufacturing system is determined primarily by adjusting cell labor, adding machine capacity only when necessary. The machine tools in the manufacturing cells to function on a make-one, check-one, move-one-on basis (MO-CO-MOO).
Job and flow shops
From 1700 to 1850, most manufacturing was performed by skilled craftsmen in home-based workshops, which is called cottage industry. But in the late 1800s, the first manufacturing system design was evolved. They replaced crafts manufacturing and used powered machines. In the early 1900s, the first vestiges of the traditional flow shop began to emerge. Flow line manufacturing began for small, high-volume items and culminated with the dedicated, moving assembly line at Ford Motor Co. in 1912. Henry Ford was the first to optimize his supply chain and synchronize its role with mass manufacturing. This mixture of job shop and flow shop permitted companies to make large volumes of identical products with low costs.
Industrial engineers emerge
Factory owners concerned themselves with individual technologies such as a developed system of engineering drawings, new cutting tool materials, and developed machine tools. Products were moved in batches from one discrete process to the next through the job shop, and a few people concerned themselves with how the factory operated. In the early factories (1850-1900), the workers figured out how to make the goods and schedule their work, without industrial engineers, production planning, and control departments, inventory control, quality control, or machine tool maintenance. But in 1890s, pioneers of industrial engineer profession changed this by developing methods to time study jobs and concept of scientific management, charts for scheduling, and slide rules to calculate speed and feed for machine tools from overhead drive shafts.
Flow shop and mass production
Henry Ford defined the second factory revolution which was the development of mass production and the economic scale. He called this concept Ford production system. His primary tools were the extreme division of labor, the moving assembly line, the shortage chaser to control minimum and maximum stock level, and else. What IEs now call flow shop manufacturing began in the 1900s for small items and culminated with the moving assembly line at the Ford Motor Co. Today’s moving assembly line for automobile production has hundreds of stations where the car is assembled station by station which require each task has the same amount of time. In the other hand, General Motors’ Alfred P. Sloan took a more pragmatic approach and developed business strategies for managing large enterprise. The different models evolved into a hybrid manufacturing system, which included a mixture of job shop and flow shop. Components made in the job shop fed subassembly lines, which also needed line balancing, which in turn supplied the assembly line. This mass production design let companies produce large volumes of identical products at low unit cost.
The profession grows up
Departments evolved to control the movement of materials, for planning and organizing work, for scheduling, planning, product designing, marketing, sales and so on. This organization called production system or the enterprise which grew in size and complexity and became the home of the industrial engineer. After World War II, the mass production machine thrived, enabling automobile producers to make cars in large volumes using economies of scale.
Toyota Production System (TPS) enhanced the idea that new manufacturing system designs spawn industrial revolutions and bring one or more companies to the forefront of the industrial world. TPS began with a new U-shaped manufacturing cells design of Taiichi Ohno’s machine. This new lean design differed from the mass design because many critical control systems were integrated into the design. Relentlessly reducing waste is viewed as a system level goal and the way to reduce cost, so basically Toyota recognized that it had to minimize and fully use the direct labor and the direct material. The lean system is designed, operated and managed so every employee understands how the system works. They are involved heavily in quality control, machine tool maintenance, and setup reduction. In 1990, Toyota’s system was given a name that would become universal, “lean production,” and the third factory revolution became widely recognized.
Lean manufacturing cells
The redesign of the mass factory features manufacturing cells linked to subassembly cells, which are linked to the mixed-model final assembly line. The lean system is operated by a unique production control system. Cell design is work for the lean engineers. The processes are redesigned so that the machining times are less than the cell cycle time. The number of the units in the cell is controlled so the throughput time remains constant. However, this system has not been published widely by Toyota as the manufacturing cells hold many proprietary processes.
Green manufacturing has the goal of zero waste to the landfill. Eliminating waste at the source using lean techniques accelerates the process of achieving zero waste. This principle are being developed and published worldwide. Green engineering, like lean engineering is a pervasive conviction that people are responsible for the current and future impact of wasting natural resources and squandering energy. The lean engineer merges lean, Six Sigma and green engineering into a unified, coherent, and modern approach to manufacturing system design, operational improvement, and process control. Changing the manufacturing system design to lean also will require a change in the enterprise design to sustain lean and the economy of scope. Thus we may say that engineers make things; industrial engineers make things better; lean engineers make things better, faster, cheaper in flexible way.