Lean or Anorexic

One piece flow

The principle of the one piece flow is useful in areas where a lot of varieties make up a very complex final product such as in the final assembly of cars. Another example is high volume manufacturing of components for engines, transmissions and other powertrain components where high precision and quality are critical elements.

Cell manufacturing has many draw backs.

When you manufacture high volume components with no derivatives or with just a few deviations, cell manufacturing sometimes make sense. The most common cell solution is to build small dedicated and non flexible sequential lines with very small machines and a minimum of automation in order to reduce space. This is quite common in Japan where the lack of space is the major restriction. When an increase in volume or a new variation is required, new cells are added. This principle depends heavily on a very stabile and predictable demand and on manufacturing in just a few locations to achieve volume. When demand drops, the equipment can seldom be used for anything else.
The main driver behind the cell manufacturing idea originates from the Japanese way of organising the work flow around the principle of Takt time and JIT. The ever-changing variation of the Takt time and the problem with non existing space in Japan means that only humans are flexible enough to be able to cope with these daily changes in volumes. Extremely flexible working patterns is also required to achieve the goal. The most common way is to organise the factory flow in a sequence of small U-shaped cells as this is the form that has the highest density of people and equipment per square meter. It is by no means the most cost efficient way when space is available.

In both these cases it is not possible to introduce continuous flexible flow methods or flexible processes based on automation because this requires more space than what is available. It also means that these methods are based on a very high labor content which will make it difficult to be a lean producer in the long term perspective unless you can maintain high volumes through a large market share.

Use space to create higher flexibility and speed

Where space is an available commodity and high operating costs are not desired, it makes more sense to develop and to introduce methods that may use a little bit more space but can be designed to be able to react quicker to the changes in the market demands. The system that has the lowest operating cost and/or gives the shortest time for Concept-to-Customer is a winner.

Around the world during 40 years

EWAB officials have over the last 40 years toured thousands of automotive and other industrial plants around the world and seen mass production vs lean production in many shapes and under many different names and conditions. We therefore have a unique knowledge and understanding of the industry, especially the automotive. We understand what works, what doesn't and why, and this understanding have formed EWAB Flow Technology

The lost competence

European industry did not have the US mass production heritage and could approach thing differently. Many plants was on the right track and had competent staff that also knew what worked, what didn't and why!
During several periods of outsourcing and downsizing a lot of this knowledge and competence has been lost. Companies have later tried to in source the lost competence by engaging consultants and/or students from universities, where very few have had any real life experience of manufacturing and mainly pre-assumptions of theoretical metaphors.

Misunderstandings and pre-assumptions may lead to anorexia

Many lean metaphors are believed to be real life examples and are used as the true way.
When industries outside Japan attempt to implement Lean Manufacturing, they do so without realising some key elements that have driven the Japanese industry to do what they do. In many ways these key elements are unique to Japan and does not apply anywhere else.

The seven types of waste

Most of Ohno´s ideas are based on minimising the use of space as space is the most precious commodity in Japan. Many of the tools will improve throughput and quality, also when and where space is not a problem. It is a common belief that the Japanese industry is highly automated but that is not always the case as safe automation takes a lot of space. The lack of space is the main reason why few robot applications has any guarding in Japanese factories.

The limitations in Japan are unique

Japan consists of 3,900 islands with a total land surface of 378,000 km². Of the total land surface, only 30% or around 110,000 km² can be inhabited. One third of this land is used for agriculture production which leaves only 70,000 km² for the 127 million Japanese to live on. This gives a density of more than 1,800 people per km². Japan has no significant natural resources and has to import almost everything in large quantities.
The State of Michigan with its 150,000 km² has more than twice the size of inhabited land available compared to the whole of Japan! If USA had the same population density as Japan, you could almost fit in the whole of the US population into Michigan!! In this perspective it becomes quite clear that the driving factor for all the productivity improvement tools used in Japan is based of the lack of space. If you have no space and there is no way of getting any more it becomes extremely precious.

The importance of space

In the rest of the world there is no shortage of land, space or natural resources. This means that the main driver for the Japanese methods does not apply anywhere outside Japan. Having too much space is also a problem which is what caused the Western industry to fall behind. The existing excess space was often used for the wrong things. Mostly to create off line buffers which in turn disrupted the process and then reduced quality. A lot of the Lean tools are very useful specifically in reducing space used in the wrong way. The understanding of the whole chain of events that makes up an organisation’s value adding process is the most important issue. It is not the amount of space utilised in the manufacturing process. As the need to improve throughput increases to meet new customer demands, the access to readily available free space will become an important success factor. Reducing space to a minimum and measuring productivity per total square meter can therefore be detrimental to the long term objectives.

Mass production

In the USA, mass production began with Henry Ford and this focus have actually remained until very recently. Many attempts have been made to turn these mega plants for mass production into lean manufacturing plants but few have succeeded mainly because they were difficult to manage.

Sweden after WWII

After WWII, Japan and central Europe was in ruins. Swedish industry was mainly smoke stack until WWII and after the war Europe had an enormous need while the Swedish infrastructure and industry was untouched. The Swedish industry needed to change quickly to meet the new market needs in Europe and became a small volume, high tech, flexible and competitive industry in a very short period of time. Swedish industry actually went lean long before Japan, but for a very different reason.

Historic review on the “quality” issue in manufacturing

The Quality aspect of Lean Manufacturing have its roots in the 1940´s and 50´s and were originally developed by E.Deming and J.Juran to increase the quality and productivity in the manufacturing of equipment for World War II. They were later instrumental in improving the Japanese industry during the MacArthur period.
In Japan their knowledge and work was blended with other ideas in order to suit the local necessities and it was further developed during the period 1960 -1980. Many new ideas proved very successful and have since been widely spread through the works of Ohno and Imai.
What is not so well understood are the reasons why they were developed and why some of the ingredients are not ideal outside Japan.