Saturday, February 14, 2015
Waste of Over-Processing , 7 Wastes in Lean Manufacturing (SIX Sigma)
The waste of Over-processing is where we use inappropriate techniques, oversize equipment, working to tolerances that are too tight, perform processes that are not required by the customer and so forth. All of these things cost us time and money.
One of the biggest examples of over-processing in most companies is that of the “mega machine” that can do an operation faster than any other, but every process flow has to be routed through it causing scheduling complications, delays and so forth. In lean; small is beautiful, use small appropriate machines where they are needed in the flow, not break the flow to route through a highly expensive monstrosity that the accountants insist is kept busy!
Waste of inappropriate processing is a consequence of a poorly planned production process of the product.
The product does not satisfy requirements and has to be reworked; sometimes it is even useless.
The reasons for waste of inappropriate processing can be found by using the fishbone diagram.
Waste of inappropriate processing can be eliminated by a thorough analysis and continuous improvement of
manufacturing process.
Waste of Transportation, 7 Wastes in Lean Manufacturing (SIX Sigma)
Transport is the movement of materials from one location to another, this is a waste as it adds zero value to the product. Why would your customer (or you for that matter) want to pay for an operation that adds no value?
Transport adds no value to the product, you as a business are paying people to move material from one location to another, a process that only costs you money and makes nothing for you. The waste of Transport can be a very high cost to your business, you need people to operate it and equipment such as trucks or fork trucks to undertake this expensive movement of materials.
Waste of transport is a consequence of excessively long, intersecting transport paths, temporary storage, load
and unload, transport of pallets hither and thither.
Waste of transport is also caused by too detailed process breakdown and exaggerated division of work, due to
imprecisely defined intermediate warehouses and due to production in large series.
Waste of transport can be eliminated by optimizing transport paths, by defining exact locations and numbers
of intermediate warehouses and by a transition from large-series to small-series or even individual
production.
Waste of Inventory, 7 Wastes in Lean Manufacturing (SIX Sigma)
Inventory has to be stored, it needs space, it needs packaging and it has to be transported around. It has the chance of being damaged during transport and becoming obsolete. The waste of Inventory hides many of the other wastes in your systems.
Waste of unnecessary inventory is similar to the waste of overproduction. Just like overproduction, supply of too large quantities leads to the waste of unnecessary inventory. Costs upon exit from the warehouse consist of costs for purchasing material and products, order-launch costs and inventory costs. High costs are therefore related to storage and they can amount up to 20% of the product sales value. Waste of unnecessary inventory can be minimized by defining optimal, maximum and minimum inventory, as well as exact time when the ordered quantity should arrive at the warehouse.
Waste of Motion, 7 Wastes in Lean Manufacturing (SIX Sigma)
Unnecessary motions are those movements of man or machine which are not as small or as easy to achieve as possible, by this I mean bending down to retrieve heavy objects at floor level when they could be fed at waist level to reduce stress and time to retrieve. Excessive travel between work stations, excessive machine movements from start point to work start point are all examples of the waste of Motion.
All of these wasteful motions cost you time (money) and cause stress on your employees and machines, after all even robots wear out.
Waste of unnecessary motion is clearly visible when holding and depositing products. Workers sit by the conveyor belts and put together parts in order to make the final product. The main element of the assembly line is a conveyor belt, so the waste consists of reaching and depositing. The main reason for waste of unnecessary motion is the sitting work of workers, which reduces workers' moving area and eliminates mutual help of workers. Waste also occurs because of one-hand work: a worker holds the part with his left hand and he uses just one hand for manufacturing activities.Waste of motion can be considerably reduced by a transition from a conveyor belt to the U-shaped production lines.
Before:
After:
Waste of Defects, 7 Wastes in Lean Manufacturing (SIX Sigma)
Waste of manufacturing defects appears on locations where semi-manufactured products accumulate and
therefore intermediate storage is required.
It is possible to eliminate waste of manufacturing defects by training workers to control the workplace,
product and circumstances:
The worker who manufactures a particular part should have the possibility of supervision how this particular
part was manufactured at his predecessor.
The worker who has just finished a particular part should check it immediately.
The worker who has finished a particular part should also build it in in his workplace.
Waste of Overproduction, 7 Wastes in Lean Manufacturing (SIX Sigma)
Overproduction can be eliminated by informing and convincing the workers that they have to stop working the moment when the daily production plan has been achieved. It is better that workers do not work than that they do something that they do not need.
How to Remember the 7 Wastes (Six Sigma)
There are a couple of Simple Mnemonics that you can use to help you remember the 7 Wastes. The first is to ask your self “Who is TIM WOOD?”
TIMWOOD
- Transport
- Inventory
- Motion
- Waiting
- Over Processing
- Over Production
- Defects
An alternative is
WORMPIT;
- Waiting
- Over Production
- Rejects
- Motion
- Processing
- Inventory
- Transport
Using either TIMWOOD or WORMPIT will help you to remember your seven wastes, very useful if you are training others and have to list them out on a board.
History of Lean (Six Sigma)
After World War II, Japanese manufacturers were faced
with the dilemma of vast shortages of material, financial,
and human resources. These conditions resulted in the birth
of lean manufacturing concept. Toyota motor company, led
by its president (Toyota), recognized that American automakers
of the era were out-producing their Japanese counterparts;
in the mid 1940’s American companies were outperforming
their Japanese counterparts by a factor of ten. In
order to make a move toward improvement early, Japanese
leaders, such as, Shigeo Shingo and Taiichi Ohno, devised a
new, disciplined, process-oriented system, which is known
today as “Toyota Production System” or “Lean Manufacturing”
(Abdullah, 2003).
Taiichi Ohno, who was given the task of developing a system that would enhance productivity at Toyota, is generally considered to be the primary force behind its system.
After some experimentation, the Toyota production system was developed and refined between 1945 and 1970, and is still growing today all over the world.(Liker, 2004). In 1980s, products were being brought to the market with higher quality and lower price. Consumers came to expect higher quality and lower prices as a requisite for purchase. Some manufacturers faded away while others began to look diligently for better ways to compete (Hobbs, 2004). In order to compete in today’s fiercely competitive market,
US manufacturers have come to realize that the traditional mass production concept has to be adapted to the new ideas of lean manufacturing because the Japanese companies developed, produced and distributed products with half or less human effort, capital investment, floor space, tools, materials, time, and overall expense (Khatri, et.al, 2011).
Taiichi Ohno, who was given the task of developing a system that would enhance productivity at Toyota, is generally considered to be the primary force behind its system.
After some experimentation, the Toyota production system was developed and refined between 1945 and 1970, and is still growing today all over the world.(Liker, 2004). In 1980s, products were being brought to the market with higher quality and lower price. Consumers came to expect higher quality and lower prices as a requisite for purchase. Some manufacturers faded away while others began to look diligently for better ways to compete (Hobbs, 2004). In order to compete in today’s fiercely competitive market,
US manufacturers have come to realize that the traditional mass production concept has to be adapted to the new ideas of lean manufacturing because the Japanese companies developed, produced and distributed products with half or less human effort, capital investment, floor space, tools, materials, time, and overall expense (Khatri, et.al, 2011).
Wednesday, February 11, 2015
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