OT Production, speeds opinions wanted

allscott

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Jul 2004
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In the manufacturing environments I have worked in machines were always run at their maximum speed. The max speed was based on whatever the limiting factor of the machine and particular product being run was, ie: bad parts, not enough cooling, motors maxed out, machine is going to jump out of the floor etc...... If we ran out of raw materials or orders, the machine stopped.

The place I am working at now has another idea. The production supervisors like to figure out either how much raw material they have or how much they have for orders and base there linespeed on that so the machines run constantly. I am strongly opposed to this line of thinking.

What do you guys do / think?
 
I, for one, am opposed to the 'full throttle' theory...just bad practice. You don't floor your vehicle every time you drive, do you? I would hate to do maintenance anywhere this style is in effect.

The second method is better for numbers, and supervisors/management love playing the numbers.
 
They should be ran dependent on orders not raw materials.

You should be able to have the proper production planning in place to schedule the machine to the pace of the orders not the other way, you will get more production if you 'pull' the product not 'push' it through the plant.

We run slow here 50ft/min max, but that is machine driven not raw material.

Faster is not always the fastest, when I was in the printing industry, we had large printing presses, the slow ones... night after night would out run the fast 'new' ones, we would run 8k impressions a hr on the slow ones and up to 12-15k/hr on the faster ones, but at that speed you always had issues with everything, it had a lot to do with the paper, a lot can happen to a sheet fed press at that speed, a ton of mechanical cams passing the paper from one cylinder to another, on jam can set you back a hr...that’s 8k more on the other press, now you playing catch-up.
 
Let me clarify a bit. We have some machines that are designed to run say 100m/min. We quite often run them at 40. However to try and shut one of these machines down to do maintenance is a problem because they are always running. They run just fine at 100, no breakdowns becasue of the speed and the product is just as good.

How do you figure out what the capacity of the plant is when the machines are not running at optimal speed? How do you justify capital investment for new equipment when you don't really know what you are capable of with your existing equipment?

Don't get me wrong I am a maintenance guy first. I understand that running a machine close to the breaking point is going to cause more maintenance issues. On the flip side it is easy to run a machine slower because something isn't working right. If you don't have the goal to run to the optimum speed there is no incentive to fix whatever is slowing the machine down in the first place.

This is where I am right now, I have a bunch of machines that have been poorly maintained for years and now they can't run as fast as they should, and there isn't enough time to fix them because they are always running at "production speed". The problem comes in when there is a spike in production requirements in which case we are hooped because the machine can't run as fast as it should and the accountants/salesmen can't figure out why "It used to run that fast".
 
I thought this is what holidays are for...

Everyone else gets time for with their family and we fix every issue in the building, they come back and run like a champ :D

Don't you guys get holidays? :) we have one next week, yaha wipeee ;) can't wait
 
The place I am working at now has another idea. The production supervisors like to figure out either how much raw material they have or how much they have for orders and base there linespeed on that so the machines run constantly. I am strongly opposed to this line of thinking.

This is a horrible way to think. Unless it costs lots of time and/or money to shut down and restart the line.

One of the most costly things in production is paying the operators. More hours = Higher cost. You'd want to produce your parts as fast as possible to make good parts efficiently. Just because you have 2 weeks to make 5000 parts, doesn't mean you should slow down and take the whole 2 weeks if it only takes 1 week. You would just double your operator costs, increasing the cost of your product, and lose money.
 
I am often in sawmills. The new ones have sorters that can sort 120 board per minute. Too often I see 50% empty lugs. What is the sense in that?
Just because you can doesn't mean you should. There must be some production or plant managers that can optimize the speed vs wear formula. This formula will change from plant to plant and even under different conditions. If they can't do that then there is a need for a new production or plant manager.
 
If they can do the numbers to get production at 40 and the machiens will run at 100 you need to buddy up with them. They should be able to work some maintenance time in for you if your nice to them.

What I have seen is production wont give the machines to maintenance. So when maintenance gets them they hold them down and do everything they can for as long as they can. Production don't want to give the machine to maintenace because maintenace keeps them down longer than they said they would. Round and round it goes and nobody wins.

Make friends with them and maybe they will work with you.
 
CHarlesM, some one must be in charge. It can't be a US vs THEN environment. If so then you are right, no body will win. Someone must be in charge and weigh all the facts. If one can speed up the line by 12.5% and get the same job done in 7 hours that would have normally taken 8 hours then there is time for 1 hour of maintenance. This assumes one can speed up the line or that there isn't a big order back log. The manager must optimize the use of time, machinery and people. There are a lot of variables to optimize. The managers can justify their pay by just being 97.5 percent of optimal versus 97%. No one has perfect information or will make perfect decisions but I bet there are some that consistently optimize better than others.
 
allscott said:
What do you guys do / think?

Its called lean manufacturing. Lines are balanced (that means some machines have idle time) and it has been proven to generally produce less scrap and more profit. Your company is in business to make money, not widgets.

Lean manufacturing lets actual orders drive production, not raw materials, and production should be pull, not push.

We switched to a lean manufacturing model and found we were actually able to meet more orders on time, scrap went down, overall factory through put went up (even though sometimes we had idle machines and idle operators) and the amount of time product took to flow through the plant went down. Google lean manufacturing and learn why it works - undo some paradigmns that make it seem counter intuitive, because its actually not.
 
Should you drive 75mph between stoplights so you can check your tires???

I have worked with processes that greatly benefitted from a slow and steady pace in the rubber industry. I have mostly worked with processes that are run beyond their ideal engineered capability. Both cases, they were doing what is best for business.

Do the math and solve for dollars. Without production at the lowest cost there are no machines to maintain. No reason for safety, etc, and so forth. Maintenace is a service to production, we must bend to their wills at times, but always argue your side and solve for dollars.

They, who lack your technical comprehension, can understand cash. And, you will learn about the true costs of maintenance versus the short term savings of eliminating it!

The forces of business do often put engineering and production on opposite sides of the table at times. We are a necessary evil to the bean counters, our talents underutilized,...somebody jerk the soapbox out from uder me, please...

If you are throwing away maintenance opportuniies and suffering run-time failures that can be calculated to the dollar, then you should be able to justify some minimum operator set up paramters and hard wire them into your plant policy and control systems to whatever degree necessary to ensure they're followed.

Good Luck!
 
I have read all the foregoing. To me this term lean manufacturing is just another management slogan catch term of the week, quarter, year era whatever. At Boeing they call it flavor of the week.

What it boils down to me is get maximum production at NOT least BUT best cost. So this means you gotta have all them overhead guys Safety, Maintenance, Engineering, etc etc to make sure we are not throwing money out the window.

I think we in America waste too much time with this slogan stuff. An example is 5S (sort sweep etc etc). Mom taught me all that stuff clean your toys when done, put them away, oil them to avoid squeeking, fix them when broke. The part that gets me with 5S is management just seems to love to jump on the most useless part of the whole program paint lines on the floors. Once that is done the whole program goes away and it is back to business as usual. Instead they should be looking at the management of the company and concentrating on cleaning up their act.

Next year you wont hear lean BUT you will hear something else. Won't matter it is the same male bovine excrement and things will generally stay the same.

Dan Bentler
 
The Train Line Theory

Speed like most production parameters can be approached whereby you identify the low and high limits (the train lines) and then attempt to run somewhere in between. For most parameters you usually pick the middle. For speed, if you have a large difference between the low and high limits then you can choose to operate above or below the middle taking into account other factors.
The significant advantage of the train line theory is that it avoids the situation where the operator adjust a particular parameter until it just works. Then something changes slightly and it then fails to work resulting in bad product or downtime.
 
leitmotif said:
I think we in America waste too much time with this slogan stuff. An example is 5S (sort sweep etc etc).
Dan Bentler

5s? Pffffft, we had 6s's awhile ago. Someone pulled an extra "S" out of there "hat" somewhere, and probably got a big promotion because of it too.

Off the top of my head, heres some acronyms and other slogans that were supposed to magically improve production: 6s, Lean, Kaizon, SMED, TIM, SBU, and probably a few more that dont come to mind.


leitmotif said:
Once that is done the whole program goes away and it is back to business as usual. Instead they should be looking at the management of the company and concentrating on cleaning up their act.

Exactly! I swear that in large companies, top management has absolutely nothing to do except for try to find ways to justify there jobs.

All of us people that are actually on the plant floor and working with the product and machinery, laugh at such nonsense. Maybe if management got out of the office or one of there many meetings, they might get a clue to how things really are.
 

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