Cellular Manufacturing vs. "standard line concept"

[tomikcz1]

Hi All,
I read a lot about cellular manufacturing, definitions, limitations, advantages etc. I am junior IE in the consumer repair centre. We have 4 separate lines, on each slightly different product – 1500 units per day/line. Our lines are 200’ long and our process has 14 process steps (operations). I was asked by my boss look into the advantages of changing our layout (process) into cells. But I somehow cannot see the advantage. Does someone has experience with changing non-manufacturing but repair/service production to cellular, when 80% of operations are testing, where machine (PC) time is equal to manual time?


Sorry for the long sentences, hopefully you’ll understand.


Tom

 

[DanteCaspian]

Tom,

Cell= The layout of machines (or processes of people), often of different types, performing different operations in a tight sequence, typically in a U-shape or L Shape, to permit single piece flow and flexible deployment of human effort. Most desirable is a cell that is catering to a product family.
The purpose is to have an arrangement of people, machines, materials, and methods in such a way that one piece flow (or in some cases controlled small batch) is maintained through he sequence of process, in your case 14, in well timed continuous flow.
If that is what you have now, don't change; or perhaps look only at changing the shape, for now, but you have to ask, what value are you adding. If there is something wrong, what specifically are you wanting to improve? Is the goal of investigating this change in effort to increase machine utilization, less operators, more automation, less materials present, less waste?
There is another side of cell production that addresses the team elements and the autonomous elements of a "factory with in a factory", i.e. building quality management in by equipping and enabling the willing workers, if you are looking at that side.
The premises here apply to all areas of work. I have done this in offices, factories, and service centers... your just looking a flow with layout in mind, often a good place to start.

 

[Mikael]

What would be the cost (worst scenario) if you do a test for just 1 line, or part of it - if possible? And even if it turns out to be a bad idea, could the process of thinking about and do the set up, reveal something valuable?

Doing business is also includes to take the correct risks!!!

 

[bobdoering]

If that is what you have now, don't change; or perhaps look only at changing the shape, for now, but you have to ask, what value are you adding.

Good point. Often a "U" is used if it helps to have operators in close proximity to either communicate issues or watch a process if someone has to leave. That may not readily apply to your process, you will have to determine that. But, having parts enter and leave near the same spot can allow mixing, whereas single line input/output has input and finished goods nicely separated. Have inputs and outputs in the same area also helps material handling to some degree (one stop shopping), but, again, it depends on the resources.

If there is something wrong, what specifically are you wanting to improve? Is the goal of investigating this change in effort to increase machine utilization, less operators, more automation, less materials present, less waste?

Good question, ponder what is broken before you fix it. Where is the benefits? What is the material flow to each station (supplies, parts, etc.)?

 

[BradM]

Generally, cellular manufacturing is more applicable to customization work. Say you are making custom components with five different work stations. If you can set up cells, each cell can specialize a bit and work on the project/customization a little more efficiently. Thus, you are able to work a product from start to finish. It will tend to accumulate less Work In Progress (WIP), if you have adequate people in the cell, or people cross-trained.

That is not to knock the straight line. Having your process arranged by work stations can also be pretty efficient. You can kick out a whole lot more product through the straight line method. Too, having no-shows for particular positions will show less with straight line. It will create bottlenecks and WIP buildup, but will still get stuff through. If work station 3 is not covered in the cell, everything will stop at workstation 3.

Also, the supervision changes. With straight line, you can have a welding supervisor, inspection supervisor, etc. With cellular, supervisors will need to be cross-trained, so as to better supervise all stations.

Finally, the flow of materials, WIP, and finished product will change. If these are forklift items, consider the different paths forklifts will take, and the # of trips will probably change.

Just saying, cellular design is great, if it is a good fit for your application. Be sure to add up all the costs, take all the different factors into account, watch your queue to assure production doesn't suffer, and/or different stations are starved for materials/WIP.

 

[Mikael]

Generally, cellular manufacturing is more applicable to customization work.

What about the concepts ofmass customization then???

 

[BradM]

What about the concepts of mass customization then???

Well... it seems like a bit of a dichotomy. I mean, every customization shop is compelled to work very fast and produce a lot, but I would not label that mass production.

What were you thinking of here? It may be possible to mix the two also.

 

[Mikael]

Well the concepts of Mass Customization is not new:

http://en.wikipedia.org/wiki/Mass_customization
(look for the headline "Variants", where different types is suggested).

It can be kind of complex, and often it goes togehter with modularization!

 

[DanteCaspian]

Tom, just wondering what you concluded on this.