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

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Cycle Times

Views: 1380

#44151

Cycle Times | 25 September, 2006

Hi Guys looking for some help from you clever dudes,Firstly I am having dificulty convinicing operations that they cant produce more boards than the line is already producing, what I am basing my cycle time on is the following, the longest cycle time

of 48sec so my calulation is 60x60 = 3600 / 48 x .7

I am using a 70% efficiency which equals 52 pcb/hr

how do you guys calculate

When not so many reel changes the line can hit 58 pcb/hr

reply »

#44153

Cycle Times | 25 September, 2006

John,

Your calculation looks fine. If that's all you were looking for your done. If you really want to produce more boards per day we would need more info. Size of board, can it be panelized or larger panel. Your line configuration and what machine has the longest cycle time. Could some components be shifted from the longest time machine to the shortest time machine. Jerry

reply »

#44158

Cycle Times | 25 September, 2006

Your capacity can be no greater than the slowest machine on the line.

reply »

OZGURV

#44230

Cycle Times | 29 September, 2006

> Hi Guys looking for some help from you clever > dudes,Firstly I am having dificulty convinicing > operations that they cant produce more boards > than the line is already producing, what I am > basing my cycle time on is the following, the > longest cycle time > > of 48sec so my calulation > is 60x60 = 3600 / 48 x .7 > > I am using a 70% > efficiency which equals 52 pcb/hr > > how do you > guys calculate > > When not so many reel changes > the line can hit 58 pcb/hr

Why are you using 70% efficiency ? Why do you choose 90%?

reply »

#44234

Cycle Times | 29 September, 2006

Does that 48 seconds include board handling?

Make sure you pick the slowest spot on the line, and time from a board untill the next board reaches that same spot. For example if machine 2 is your slowest you can pick any part of the cycle. Maybe first placement but make sure you time from first placement of the first board untill first placement of the next board. Or you can time from start of loading of the first board untill the start of loading of the next board. And it would be much better if you can time multiple consecutive boards this way. Unfortuneatly parts always seem to run out when doing this which messes up your cycle time measurements.

If I can sneak a rant in here. You will have either people or the line at times doing nothing. Either the machines will be waiting sometimes for busy operators or operators will be waiting sometimes for the machine to go empty.

reply »

Fluid Dispense Pump Integration

SMT Services - STI Electronics