Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Production Line Setup

nuezmaster

#20284

Production Line Setup | 7 June, 2002

I am having some diffuculty convincing our exec. staff that by increasing our personel on the floor, we will actually improve our machine efficiency. We currently have seven lines, four of them have two P&P machines in line. At this point there is only one technician per line controling, operating, and inspecting the whole process. I am looking for some publications or studies that will help me out.

Thanks

reply »

#20285

Production Line Setup | 8 June, 2002

It should be easy enough for you to do your own study to determine if you need more people or not. The first thing that I would do is optimize or balance your line to the optimum efficiency. That is not a difficult task. Once that is done, analyze your down time reaction or response times with the current labor in place. Determine if the equipment is idle an excessive amount of time waiting for operators while the machine is either out of paste (in the case of a screen printer) or awaiting parts replenishment (in the case of placement equipment). If you determine that the machine sits for 10 or 15 minutes waiting for a human to perform a 2 minute task, then you have an issue. Also, a study in machine failures and the reaction times from your technicians will yield a few good points such as what equipment is giving you the most trouble and why and the time it takes to repair these faults. This lets you know who your best people are and who needs further training. It's not always better to have more people in the process. Sometimes a combination of process fine tuning and operator/technician ability enhancements will get you where you want to go.

reply »

#20288

Production Line Setup | 8 June, 2002

At each of the machines we have a log book.One of the sections that the operators fill out in the log is called machine downtime, and next to it is a comment section.Any time the machine is not placing parts they make a quick note of why they are down. This is kinda a quick way to get an idea of what is going on. Also I don't know what kind of lines you are running, but it is almost impossible for one person to tend a pick and place line by themselves.We try to keep at least two people per line.

reply »

Ken Bliss

#20292

Production Line Setup | 10 June, 2002

By centralizing to your stockroom all your feeder setups so that one team is assigned to just that, to keep all your 7 lines up and running will reduce the amount of personnel you need and increase throughput. Keep in mind a key factor. The bottleneck of an SMT line is (and should always be) the pick-and-place machine(s). Keeping this bottleneck running as many hours during a staffed shift as possible is mandatory for maximum plant efficiency and throughput. Making every effort to minimize downtime during product changeovers, feeder exhausts, maintenance and programming is the foremost critical steps to ensuring your bottleneck is kept running. Considering all mandatory downtime on an SMT line, the percentage of uptime should be closer to 75% - 80% of a staffed day. For more information on how to increase your SMT line efficiencies, download the following white paper on Profit-Driven Manufacturing. http://www.blissindustries.com/profit-drivenmanufacturing and be sure to calculate the economic returns of recapturing this capacity at http://www.blissindustries.com/calculator.

This should give you the answers to your questions or give you ammuition to present to management and the white paper will definitely help focus your efforts on the areas of the line that count the most.

If you�d like to speak with me directly, you can at 510-490-8401.

reply »

#20294

Production Line Setup | 10 June, 2002

Gotta hand it to you Ken. Quite a piece of marketing to sell feeder carts.

reply »

Stephen

#20296

Production Line Setup | 10 June, 2002

My take on it, is that you can't exactly match labour to machine requirements. So the question is, which are you going to focus on? Keeping the machine busy or keeping the people busy. One or the other will have "waiting" periods. To me because the machine can produce so much more than a person, keep it busy, and don't worry if operators occasionally have 2 minutes here and there where they are not running full out. The main thing is to keep the machines going full out and not waiting for people.

Stephen

reply »

Mark J

#20365

Production Line Setup | 14 June, 2002

Never try to convince an exec. staff to change manning policies using efficiency, it's a losing cause. Look at your audience, they probably all have MBA's which means they only look at the dollars and cents. To them those aren't production machines on the floor, they are money pumps. Not their fault, thats the way they're trained. To them the technician/operator is, in theory the best possible solution to their manning problem. More bang for the buck so to speak. The problem is that this theory is as good as the one that states that bumblebee's and hummingbirds can't fly. You might try arguing that fewer high priced tech's and more low priced machine operators would reduce downtime,meaning more product out the door, which equals more money in the pocket. This also has the added benefit of allowing the tech's to do what they're trained for, to keep the equipment in top shape and be more pro-active on preventative maintenance. This would mean fewer breakdowns, reducing operating costs (spare parts are expensive). You'll have to do some studies, but they'll prove out the point. I've yet to see this concept of owner/operators work. although someone out ther may have made it work after a fashion.

reply »

nuezmaster

#20373

Production Line Setup | 14 June, 2002

Thanks for all the advise. I was able to recruit one person for a week to inspect boards after pick and place and was able to show a 65% efficiency increase for that line. Now I have a req. for 5 more people.

Thanks,

Nuez

reply »

ianchan

#20416

Production Line Setup | 19 June, 2002

Nuez :

u mean u put an operator to check the placement mounting of components, juz before the PCBA enters the reflow oven? how does that release the bottlenecks for efficiency rates? pls explain, coz we want to learn from your experiences. Thanks.

reply »

nuezmaster

#20421

Production Line Setup | 19 June, 2002

The problem that my exec. had was that he did not want to add too many people to the department because there is no telling how long the demand will stay high. Therefore, I decided just to add a PCB inspector between the Pick and Place machines and the reflow oven. It would be easier to find a spot on the stuffing line for an inspector than it would for an operator/technician. By adding a PCB inspector the operator/technician pays full attention to the machine and no longer has to spend time inspecting the boards as they come out of the machine. In turn, the PCB inspector focuses only on quality and reports any defects to the operator/tech. so they can be fixed. After a week, we collected the daily run rates and it showed that we had increased our efficiency by 65%. It will take some time before we can gather information on how much the quality has increased. By allowing the Operator to focus on the machine, we have been able to reduce downtime by making sure parts are pre-fetched and loaded on spare feeders before they run out.

Nuez

reply »

Ken Bliss

#20422

Production Line Setup | 19 June, 2002

It sounds like your inspector improved quality and pre-staging your feeders dramaticaly increased uptime on your machine, thats great to hear. One cautiionary note, be careful not to flood your production area with parts off of your SMT line. With a 65% increase in throughput on the line you most likely do not have enough people in place to handle all those boards and you will increase work in process significantly, and thats not a good thing. You will want to look at your next bottleneck down the line probably in manual assembly area or test to releive it so the bottleneck goes back to the pick and place machine. If you are changing over the SMT line 1-3 times a day, consider doing more changes and running smaller batches that will reduce finished goods inventory, you can utilize the improved uptime also to run rush jobs for customers as the previous down time you recaptured is now a profit center.

reply »

nuezmaster

#20427

Production Line Setup | 19 June, 2002

Our plan right now is only to increase production on the products that we are behind on. Since we are currently running three shifts with seven assembly lines and only adding six people (3-Days, 3-Nights), it averages out to about a 20% increase overall. We believe this will be sufficient for now.

reply »

IPC Training & Certification - Blackfox

SMT spare parts - Qinyi Electronics