Getting to the Meat of Lean

The term lean production was first applied to the manufacturing sector by MIT researcher John Krafcik in 1988. In his article titled “Triumph of the Lean Production System,” Krafcik laid out the lessons he had learned at a Toyota/GM automotive manufacturing joint venture.

Lean manufacturing essentially is a set of tools designed to eliminate waste in all its forms, in all areas of a business. The theory behind the practice of lean is that as waste is eliminated, quality will improve automatically. Andon visual feedback systems, 5S, kanban pull systems, kaizen continuous improvement strategies, and bottleneck analysis are all tools in the lean toolbox.

While not all shops will easily Jack Sprat their way into a leaner operation, the lessons and strategies of lean can be applied to any shop, of any size, in any location.

Because the origins of lean manufacturing began with—and are hard to separate from—the Toyota Production System (TPS), many shops believe that it is a process that makes sense only in large shops with high production numbers. This is not the case, however. This is, in fact, one of the classic myths surrounding the implementation of lean, according to lean guru and Spacefile International Corp. Vice President of Operations Bruce McDonald.

Some other lean myths are that lean is expensive to implement, that it works only in high-volume, low-mix production environments, and—the granddaddy of all lean myths—that it doesn’t work at all.

“The reality for most production shops is the sooner and smaller you can begin the implementation of lean, the easier it is to implement primarily because you have less complexity in the work,” said McDonald.

Lean at All Shops

Not only are smaller shops typically less complex in terms of the work needed to implement lean practices, but the focus on improvements becomes clearer because smaller shops do not typically have multiple layers of staff between the manager, who is quite often the owner, and the shop floor employees. In fact, there typically is a clear line of sight from ownership to the manufacturing processes.

“All of the tools of lean are applicable to any size business too,” said McDonald. “The order that you roll them out and apply them is different for each situation, however, and they are only as effective as the leadership is committed to adopting them.”

Typically, 5S is applied early on as a launch point for the transition to lean. Part of this is due to the ease of doing 5S, and it also helps to begin the developing of the discipline necessary to carry on the transition.

5S Methodology

• Sort
• Set in order
• Shine
• Standardize
• Sustain

According to McDonald, a business of any size can benefit from lean tools because the tools themselves are scalable.

Typically, a company looks at its customer’s requirements and tries to fill them using lean manufacturing techniques. A value stream from order to delivery of product should then be mapped to analyze where improvements can be made. This is done through repeated cycles of improvement activities, known as kaizen.

Kaizen and 5S are just two of the many lean practices that can be implemented. It’s possible that they already are being practiced on the shop floor as part of its day-to-day operation, without being called lean.

“Many shops practice various aspects of lean manufacturing without knowing that they are. When a shop makes a change to an existing process to reduce scrap, or to make it faster, or to reduce raw material consumption, or to improve quality, they have just done a kaizen event,” said McDonald.

A common practice in shops is to find ways to reduce the setup time on equipment. By doing so these shops are practicing SMED (single-minute exchange of dies). If a shop adds sensors to the equipment to prevent defects or tool damage, or if it adds ejectors to stations so that manual load/unload is reduced, it is practicing jidoka (automation with a human touch).

“Almost every shop practices aspects of lean manufacturing whether they realize it or not,” said McDonald. “The difference is that they can be haphazard and have very limited impact on the operation because the effects of the change are localized and do not flow through the entire value stream.”

An example is a shop that increases productivity in one operation, but creates work-in-process (WIP) that just waits longer downstream for processing in other operations. While there has been continuous improvement (kaizen) with Operation 1, there is no improvement because of the waste (muda) elsewhere in the value stream.

“Lean is a way for businesses to organize the value stream. It is a different way of looking at how to conduct business and attacks problems in a relentless and organized methodology,” said McDonald.

Implementing Lean

McDonald’s advice for taking the first steps to implement lean practices is to find a sensei. This doesn’t necessarily mean hiring a lean consultant, either, but rather talking to people who know about lean manufacturing and doing some research. Many knowledgeable individuals are willing to give freely of their time to discuss the fundamentals of adopting lean and the benefits that can accrue. In addition, many books and courses on the subject of lean manufacturing can help explain its benefits.

Being successful in the implementation of lean manufacturing ideals first and foremost requires commitment; commitment to the ultimate goal, the staff, and to the process.

“The tools of lean are not as important as the reason why the tools are used,” said McDonald. “All of the tools and principles have a specific reason why they are employed, and they all focus on creating the perfect process.”

For example, according to Mc- Donald, many manufacturers think the purpose of the lean practice of kanban is to regulate and control inventory. The true purpose of kanban, however, is to get rid of the necessity to carry inventory.

“Kanban is a form of waste, pure muda. In the current state of the specific process, it may be necessary to carry some inventory, but to think you have done something by introducing kanban is wrong. It is only when you can get a process to operate in a continuous 1-by-1 flow without accumulating inventory, and do so at a pace that will equal customer demand, will you be moving toward achieving lean,” said McDonald.

When you achieve this 1-by-1 flow without the need for kanban, the work of continuous improvement persists through the philosophy of kaizen, the incremental daily improvement activities that underlie and sustain continuous improvement.

Visual Indicators

So how do all of these lean concepts translate to the shop floor?

Visual indicators, such as dashboards, are an important tool in the lean toolbox. They provide an opportunity to see at a glance the status of important information such as the production plan, downtime, cycle time, reject rates, and changeover time.

When managers can simply walk out to the production floor and see instantly if orders are late or on time, if the quality of the parts produced is still good, and if the delivery of the order is still on track, they spend more time on planning than chasing information. Waste is eliminated.

These visual indicators typically are among the key performance indicators (KPI) for the manufacturing facility, so they are important to track.

“I cannot imagine successfully running a business without tracking KPIs,” said McDonald.

While some of the main KPIs most small to medium-sized businesses track are sales, profitability, and some measure of quality (returns, warranties, complaints), the area where the vast majority of businesses have difficulty tracking KPIs is on the shop floor.

This has a major impact on the performance of the organization in terms of business development, the ability to increase sales without increasing fixed costs, and its profitability created through continually driving down costs associated with muda, mura, and muri, the three Ms of waste.

Perhaps the most important of the KPIs related to the shop floor is overall equipment effectiveness (OEE).

OEE is a measure that breaks down the manufacturing unit (plant, department, or even machine) into three main measurable areas: availability, performance, and quality.

“It is clear to me that OEE as a key metric is as important a metric to any organization as sales and profitability,” said McDonald. “It is arguably the most important of the production metrics because you are measuring the state of your organization through the lens of organizational efficiency, including total quality management (TQM) and total productive maintenance (TPM). When tracked it forces an organization to look deeply into cause and effect to improve performance in such areas as production planning, setup time, quality, cycle time, and process efficiency.”

Implementing a lean manufacturing strategy is one way a business can organize itself and then operate for the rest of its existence.

“Lean is not a toolbox full of principles and techniques; rather, it is a philosophy that is easy to conceptualize but incredibly difficult to achieve,” said McDonald.