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Cost Per Placement

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SMTA-Shafiq

#81127

Cost Per Placement | 1 October, 2018

Hello All,

I'm looking at performing a cost analysis to calculate cost per placement at SMT. I've read articles and many suggest simplifying it to labour cost (hourly rate x # of operators) / # of placements per hour.

Other angle to this is evaluating BOM reduction. I'm looking at reducing the number of unique part numbers if there are duplicates (ex: Three different 0402 packages with the same resistance and power rating). I want to evaluate the cost save of reducing 3 different part numbers down to 1 part number. The savings would be in reduced cycle time, feeder, part purchase and inventory.

Any advise on how on formulations that you might have used will be helpful.

Thanks.

This message was posted via the Electronics Forum @ SMTASMTA

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#81132

Cost Per Placement | 2 October, 2018

Now you are going too deep. Purchasing should have nothing to do with your placement cost. Reducing part numbers too. These are separate processes and should be evaluated separately. You have:

1. Machine time and cost -utilities -maintenance -consumables 2. Labor time and cost -Salaries from purchasing to the cleaning person 3. Building costs -rent -utilities -maintenance

Add all these and divide on your number of placements. That will be you total cost/placement.

For SMT - subtract the factors that don't apply. You will end up with: -operators salary(setup and machine) -machine maintenance and utilities costs -number of components per hour

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SMTA-Shafiq

#81218

Cost Per Placement | 12 October, 2018

Thanks Evtimov.

I was actually looking for both.

1. Cost per placement For SMT: Your proposal is the following?

(Hourly labour rate of operator + hourly machine & maintenance cost + hourly utilities cost) / # of components placed per hour

2. This is a separate project but also related to the first one. Idea here is that if I reduce the number of unique part numbers on an assembly, the cost of assembly should reduce. For example: reducing 100 unique part numbers to 95 unique part numbers. The number of placement will not reduce as the replaced part number will be substituted by another part number but the overall cost should reduce of the assembly because I'm setting up 5 less parts on the line.

Thanks for your feedback.

This message was posted via the Electronics Forum @ SMTASMTA

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#81219

Cost Per Placement | 12 October, 2018

SMTA-Shafiq

On your cost per placement: Will the through-put of this new placement machine be greater than the current lowest through-put machine on your line? The lowest through-put machine should be your focus.

On your reducing the BOM: Reducing setup time is a worthwhile activity

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#81238

Cost Per Placement | 15 October, 2018

You see, if you can optimize your product setup that will be the best. Back in the days, engineers used only standard values. For resistors for example I used to build boards having 100, 330, 470, 1k, 3.3k.....Sometimes that means you might end up with more part placements, but that's the way it was - simple setups. Now you have to pick from resistors with 0.0001 ohm accuracy, so people end up having 300part number setups....In manufacturing is so much easier to use simple, smaller setup(less time, less space, less errors)

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#81277

Cost Per Placement | 22 October, 2018

Can you describe the scenario that gives you multiple p/n's with the same specifications in the same BOM?

I can understand having multiples in your inventory (primarily if you're a CMS and have multiple listings for different customers) but not per BOM.

I must be missing something....

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SMTA-Shafiq

#81337

Cost Per Placement | 30 October, 2018

Steve,

Part numbers with the same specification are not part of the same BOM.

Scenario is, SMT Line #1 builds Products X, Y and Z

Product X has a part number #1 that is a resistor with 50 ohm value and a power rating

Product Y has a part number #2 that is also a resistor with 50 ohm value and a power rating

Product Z has a part number #3 that is also a resistor with 50 ohm value and a power rating

Problem is that we have 3 unique part numbers for a component with the same specification. The BOM Reduction project would pick only one part number (ex: part #1) and replace part #2 and part #3 with it hence reducing the total number of parts on the SMT line.

The cost savings would be from reducing part setup time by eliminating two extra part numbers.

This message was posted via the Electronics Forum @ SMTASMTA

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