The case of the high-speed slows

By KC Boxbottom in Sealers on August 30, 2012

Suppositories packagingAlex was on the blower sounding confused.

“KC, it seems like the faster we go, the behinder we get. I’m not meeting my production numbers and don’t know what to do. Can you help?”

The answer to that is always “Yes!”. After all, I am the Packaging Detective.

Soon after we hung up I was with Alex in his plant and he was showing me the problem. The product was 3/8 in. diameter suppositories and they were sealed between two strips of poly coated foil. The real problem was that the product was too thick for this kind of package but there was nothing that could be done about that.

The issue Alex was having was that the process generated about 30 percent rejects because the film didn’t seal correctly.

“Fiddlesticks on sealing rejects!” I expostulated. “Proper sealing must balance time, pressure and temperature. What’s needed here is lower temperature and pressure plus a longer dwell time. The only way to get that is to slow down the machine.”

“But our production targets are based on 60 ppm (packages per minute). If we slow the machine we won’t meet them.” Alex said.

“You’re are not meeting them now.” I told him. “Running 60 ppm with 30 percent rejects gives you an effective speed of 42 ppm. Slow it to 50 ppm, get rejects under 5 percent and your effective speed is 47 ppm. The 12 percent speed bump plus reduced rework and scrap will let you hit your numbers.”

Faster isn’t always better.

 

KC Boxbottom, packaging detective, is on the case to solve tough packaging puzzles. He is the alter-ego of John Henry, CPP. Known as the Changeover Wizard, Henry is the owner of Changeover.com, a consulting firm that helps companies find and fix the causes of inefficiencies in their packaging operations. He produces a free monthly newsletter called Lean Changeover, which contains articles and tips on changeover and related issues. Reach him at [email protected].

3 Comments

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Once agin, KC Boxbottom strums a major chord. Over my 30+ years I’ve always found people willing to increase the speed. Afterwards they trumpet their move as some kind of grand accomplishment. This NON-accomplishment was easy - all you have to do is turn a knob or dial in a higher number. It’s misguided and short-lived at best. Moreover, I’ve found others who retort “it won’t run that fast”. Weekly, or sometimes daily, they slow down the machine or line stating, “Well, you want it to run steady, don’t you?” A few weeks like that and you’re soon to be running at half your budgeted rate or worse. May as well lock the doors and send everyone home. But most people don’t look beyond the obvious. Once you move the running rate up, you need to follow up by addressing all the spots where a problem exists. While doing this, you run at the “old” rate. Then you move up the rate again. Again, you note the problem areas. A couple cycles of this familiar sounding Test-Identify-Fix cycle and you’ll soon find you CAN run at the higher rate. Otherwise, just keep fixing your issues. In the end, the higher efficiencies will produce higher throughput. That’s a better measure of successful production anyway. There are no shortcuts to world class performance. This process can be fun, exciting and very rewarding, paying back your small, targeted investments in a month or even less. In fact, it’s literally self-funding. And it earns credibility out on the floor. Everyone wins, and there’s nothing wrong with that.
You are right about your processes used to fix the issues. There is really no such thing as won’t work. There is can’t be adjust it properly or easily enough. Any problem can be overcome with proper maintenance, adjustment or modification if need be. The biggest issue I have learned is ability those adjusting and consistency of repair. What do I mean by consistency? This is, once adjusted properly will it have to be adjusted again for another variable. Knowing how to get a machine to run faster consistently is the true measure. If it has to be tweaked a couple times a shift or every few days you need to look at why and fix that variable. Many times the issue is the inability of the people making the adjustment to identify the correct adjustment to make. They make the wrong adjustment or to many adjustment plummeting themselves and the machine into chaos. Then they don’t know how to get it back to where they were, when it was running better. The biggest mistake is allowing a machine to work at a high speeds because the most experienced mechanic/operator can run it that fast thru constant attention and tweaking. This is wrong. You must look at what is being adjusted and decide what part of the process can be changed to make the necessity to tweak a machine once adjusted properly and working well at any given speed it should continue to run at that speed without issue. If it doesn’t and the machine is in good working order then other areas need to be looked at. If you can’t make an issue go away completely (%99.9+), you haven’t fixed the issue and the problem will return. Working on the idea that 85% of the time a machine is running will get you recurring issues that never get fixed. Even though some say this is world glass. I don’t count breaks or lunch as part of the missing 15 percent. If you tell me a machine works flawlessly 85 % of the time and needs preventive maintenance 15 percent of a day for known wear issues. I might agree. If a machine has cartons glued together and that causes jams that might be a reason. But, this should be addressed. It comes down to this simple fact. If you can’t or aren’t trying make a machine work %100 of the time without stopping or rejecting too much. 0.01% is acceptable, you will never get consistent production out. If you run at 100 ppm to put out 4000 and hour when you should be putting out 6000. You may meet your quota but you were down 20 minutes. If that was time for jams or machinery issues you will never get any consistent production from that process and it is out of control.
Jimmy c is on track and has hit on the tried and true method of SLOW THE CYCLE DOWN TO WHERE THE PROBLEMS ARE NON OR FEW, then after correcting ALL problems,- increase the speed incrementally - say + 5cpm, run at this speed for one hour,- check for any problems, fix same,- and repeat untill you can no longer solve your your jams or rejects. you have then reached a point where you must slow down to the last trouble free speed. If this speed is not going to meet your goals, then call in an expert on that particular machine.