Are Conveyors really Non Value adding ?

Taken form the archives /pw

Conveyors are “non value adding”!?

This is a position taken by the Japanese that has been accepted as truth in the western industry.  Very few have regarded the fact that Japanese factories very often do not have much space - the total available space for Japan society is smaller thant the sate of Michigan USA. Very few realise that most of the Japanese thinking is forced by necessity to minimise floor space. This floor space is a fraction of what western industries have available.
The very unique need in Japan have brought many good principles. Very few are new, they are to a large extent inherited from western industry but made more understood by the Japanese.

How is Non Value Adding defined?

  • Value Adding    
    • Things that I as a customer would be willing to pay for. (accept as a part of the price) Ex; defined as anything that change the shape or finction of their product
  • Non Value Adding    
    • Things that I as a customer not necessarily want to pay for but is a part of the business and can therefor not be eliminated. Ex defined as anything that supports Value Adding
  • Waste    
    • Everything else

What about “non value adding conveyors”?

Depending how value adding is defined, conveyors can be Vale Adding or Non value Adding

Non Value Adding conveyors are a conveyor that does nothing else than move a part from point A to point B which adds little value. Why? It will evidently have parts in queues and will eventually create waiting times rather than reducing waiting times. However it can improve qiaulity and reduce operating expense.

Value Adding conveyors are conveyors configured to increase utilization and thereby reduce the need for machines, reduce inventory, reduce scrap, support production in small batches. reducing the number of machines required is obviosuly soemthing machine suppliers don't like so they tend to argue against conveyors.

Waste conveyors are when the the focus is on sub-optimizing technology rather than focusing on total investment and pay-back.

What’s a conveyor?

“To convey “ means “to transport”. And transporting something from one point to another beeing just transport is by some argued to not add value. So, in some respects the pre-assumption that a conveyor is “non value adding” have it's merrits!
If, so this is valid for all types of  “transport devices” including conveyors, gantries, robots on rails, shuttles, AGV’s, etc. but how to produce anything without moving the material from operation to operation?

The sequential transfer line approach was popular for many years, but is today limited to very specific processes. Transfer lines is what often comes to mind when conveyors are discussed. The variety with parallel operations is the one being used most, while only providing limited re-routing functionality

Another trend was the cell approach. This principle is easy to understand and to implement, but does not provide either the pull or re-routing capabilities that Continuos Flow requires. Companies turned away from the cell approach to look for something else, but as it seams to be the “least bad” solution the concept is partly coming back.
Many consultants are also promoting the cell approach, as this solution is something a consultant can propose and yet not have to be responsible for.

To be continued....

EWAB and Massproduction vs Lean Manufacturing

Taken from the archives...

The effect of WW2

In the late 40's as a consequence of the war the consumer need in Europe was bigger than the capacity. Everything that was produced was sold which led to massproduction systems in both Europe and North America. The automobile industry in particular built factories for production of long series to last for many years.
Due to the events of history there was however one exception, Sweden was at the time only farming and process/smoke stack industry. The coalition governement that had been inplace during the war, realised that for Sweden to have any place in the future industrial world it had to quickly change over to a flexible industry that could cope with quick changes and short series. Sweden simply didn't have a market for massproduces products.
So , in fact Swedish indiustry went lean 50 years ago.

What does the packaging industry have to do with Lean Manufacturing

When Juran formed his Just In Time principles it was by studying the supermarkets and how they handled the problem to always keep the shelfes full. He then transformed these ideas into the automotive industry.

Another issue in packaging is the production speed. In packaging we don't talk about cycletimes in seconds or minutes, we talk about packages per minute from 60 up to 300!
At thoose speeds, there is no room for buffers and no room for anything less than 100% up-time. Any type of changed routing must be made on the fly and it can only be done if crossing paths are done at different levels.

How the packaging industry effected EWAB's development

During the 70's EWAB made applications within
Bottleproduction where speeds was extremely high (200-300 per minute) requiring extreme reliability while routing the flow to different packaging machines.
Vaccum packed coffe production where cause and effect of bottlenecks where devastating. Correct implementation of constraint theories led to 25 % productivity improvements and reducing the need for filling machines with the same amount while reducing the amount of scrap to a fraction of what is was caused by continuous stoppage in the filling machines.
Paint can filling where batching and routing was a big challange, often built in old buildings and on several floors.  
Many other areas with different combinations of high speed, routing and batching.

How the Swedish lean industry effected EWAB's development

For 20 years during the 70's and 80's the majority fo what EWAB delivered was for an industry that had been devoted to what today is called lean manufacturing for more than 30 years.  Therefor it have been with great intrest that we have studied how lean manufactruing appears as something new in the massproducing world.