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Maximum production per SMT Line

ricardof

#28957

Maximum production per SMT Line | 4 June, 2004

Hi to all, I have one question that I hope to receive comments - Does anyone know or have any experience for the maximum boards you can run on a SMT line, this is quite general, but let's consider a board 8" x 8", about 400 components. Regardless of the brand of the equipment. I understand we can run thouusands of boards with small products (i.e. panelized boards 1" x 1' or less), but in this case we're talking about normal boards (8" x 8" up to 14" x 14") a)What is the maximum you can really maintain with the Printing Process issues? b) What is the maximum you can get on the oven without any issue? c) Most important, what's the maximum that operating people can support if you run 24/7, for several weeks?

d) What would be required to accomplish this? (i.e. 150 boards/hour: Training people? Maintaining equipment?

e) is that something achievable?

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gabriele

#28958

Maximum production per SMT Line | 4 June, 2004

Hi Ricardo,

You should complete the question with more details like : - kind of components pkgs (Chips, SO,TSOP,QFP,BGA,CSP,etc) and % of them versus the total (400) - tech complexity of components (0402 ? Finest Lead and ball Pitch ? SMT connectors, etc Screen print performance is strongly depended from tech complexity of the components. Same the PnP and why not the reflow step.

Regards Gabriele

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ricardof

#28991

Maximum production per SMT Line | 7 June, 2004

Gabriele, yes you're right, but my question is more focused to restrictions as for the Operators, and then the performance in Screen Printer and Oven. The board has 400 high speed parts and 20 parts for Odd Shape machine (QFPs and 2 BGAs), Board is not complex, but since the board is not panelized, we need to have a cycle time of 24 sec. And the main question is, does anyone have the experience to run a cycle time like this, without having issues to keep the rate for long periods? (That means unexpected failures on equipment, wiping on Screen printer, feeding machines with material, etc)

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Evtimov

#29009

Maximum production per SMT Line | 8 June, 2004

Hello! About the cicle time.....24sec is impossible for 400 cmps. About the max speed: -you will need very good operators -reliable machines -big series of the products

The printing process is not the critical I think. Niether the reflow, when we talk about 400+20 components. Of course it depends of the equipment you have. But my opinion is you train very well your operators and you will need 1 technician to fix fast the problems with your machines. We all know the operators can not fix even easy things. You will have time for reload components etc.

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#29044

Maximum production per SMT Line | 10 June, 2004

If you have unlimited budget, to achieve your cycle time of 24 sec for 400 chips + 20 QFPs & BGAs you would need 2 chip shooters with placement speed of 10 placement/sec and one or two pick&place at 1 placement/sec for the vision assisted placement of QFPs... Any printer can your size of PCB under 20 sec. Oven, if you run at >20in/min you have plenty of capacity.

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ricardof

#29049

Maximum production per SMT Line | 10 June, 2004

well, my concern is not the equipment, I know we could have the lines to do that, at this time not the required space, but what about the people? I mean, the machines are not 100% human beings independent, will the people support feeding, wiping, inspecting, 8 hours per shift, 3 shifts per day? I would like to know if someone else is running at this speed? (Note: not mobile phones)

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#29059

Maximum production per SMT Line | 11 June, 2004

hum, I see no problem for your people supporting any line that can run this speed. If your chip shooters are the dual feeder carriage kind, you must run them in replace mode, when one feeder runs out in one carriage, it parks it and continues running with the other carriage, production doesn't stop during feeder replenishing. Then there is setup time, if you have lots of feeders, you can prepare a complete setup off-line, keeps change-over time to a minimum. There is still the preventive maintenance time which you must allow if you mant to minimise down-time.

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Rodion Pronin

#29109

Maximum production per SMT Line | 14 June, 2004

Hello Ricardof

I believe speaking of your example, huge boards with many components on them, a very important aspect would be the sequence in which you place your components on the board... It happends that I have a software that optimizes assembly process, that is considering the distances the placement head have to travel and number of heads, I can come up with a sequence that can increase productivity up to 2 - 3 times, especially on such big boards. If you are interested, feel free to contact me at pronin@rogers.com I will explain in details.

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#29151

Maximum production per SMT Line | 16 June, 2004

ricardof

Unfortunately I cannot comment on many of your questions however I can lead you to one important article as to basic assembly optimization techniques to maximise throughput (or minimize assembly time, which is pretty much the same thing...)

http://www.reed-electronics.com/semiconductor/index.asp?layout=article&articleid=CA71291&industryid=3026

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RicardoF

#29157

Maximum production per SMT Line | 17 June, 2004

Believe me, I don't see any problem about optimization on Placement equipment nor printing or even the oven, my concerns are with the people: - Am I on the limit to assemble about 1100 to 1200 boards per shift (8 hours)? I have seen some of our lines running 1000 boards per shift, but that was something crazy, can we do that a bit higher?

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#29159

Maximum production per SMT Line | 17 June, 2004

What do your people working on the lines have to say about it?

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