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

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


SMT COMPONENTS

Ken Bliss

#20677

SMT COMPONENTS | 13 July, 2002

Can I get some feedback from everyone, I have a few customers telling me they are having a very big problem with components coming into their factory in the wrong type package, wrong tape, Jedec tray instead of tape etc etc. They then resend them out for repackaging but this obviously holds up production. My thought was that the BOM was misspecifying the package needed for the particular board and machine, they say no. Is the component side of the industry having a big problem or is this isolated to bad communicatioins at a few factories with their vendors and purchasing.

Thanks for any input

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#20687

SMT COMPONENTS | 15 July, 2002

I see this all the time and we are an OEM that can specify how parts are to be packaged. That being said, purchasing is always having problems finding the part in the specified packaging and end up buying it however they can get it. It's not like we are specifing odd packaging, I want everything possible on tape and reel or tray, no tube or bulk. I blame a lot of this on purchasing not allowing enough lead time to order the part in the proper packaging and then when they go to buy it because we are low or have run out they say they can only find the part in the undesireable package or the vendor has not stocked enough in the correct packaging.

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Ken Bliss

#20688

SMT COMPONENTS | 15 July, 2002

Hi James

If I understood you correctly, you have this problem also but you acknowledge its not the component vendor making the mistake it is purchasing not ordering soon enough in the right package or accepting whatever they can get. I would think that would be a problem you could control by getting purchasing more involved with manufacturing so they communicate better internaly that parts coming in need to go righ back out for repackaging. One of my customers is saying that the outside vendor is supplying parts in the wrong package in violatiion of the order and when they arrive they start production and then realize they have the wrong package and that is creating downtime.

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#20694

SMT COMPONENTS | 15 July, 2002

I have found that it all depends on your leadtime. I've found that tube and tray are easier to get then taper nad reel. I figure it has to do more with the vender. It's much easier to sell small quantites (ie tubes) then to try and sell a huge reel of something. Seems like companies are looking at the amount of inventory in their stockroom again.

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#20697

SMT COMPONENTS | 15 July, 2002

�Very BIG problem� => For us, no. Pain in the butt, yes. Volume build shops do not have the inherent flexibility that quick turn shops have built into their systems to deal with these problems. I�d speculate that this issue will help LARGE contract shops to rethink the profitability of products. Those jobs will flow down hill to the smaller shops.

We think the REAL pain is when packaging �changes� within a purchase lot or package unit. Examples of �packaging �changes� within a purchase lot� are: * Parts orientation different within a tube. [Finally found a use for that GD xray machine.] * Rotation of parts within a tray. [Finally found a use for that GD xray machine.] * Rotation of parts in trays different from different suppliers.

� forcing a CAR and another �why isn�t First Piece working� witch hunt.

Regardless, we firmly believe these problems are far preferable to having NO parts.

�BOM was mis-specifying the package� => Could be, but we define packaging requirements on our purchase order, as an element of the part description.

�Is the component side of the industry having a big problem?� => * Dunno, the component side of the industry would like more business. [�A rising tide floating all boats� theory.] * Dunno, we purchase 99&44/100% of our electronic components through distribution. So, it could be the parts fabricator, distributors, or us.

�Is this isolated to bad communications at a few factories with their vendors and purchasing?� => We don�t think so. We believe is an artifact of: * Suppliers keeping low inventories. * Buyers keeping low inventories.

So, buyers save two microcents by accepting whatever stock the suppliers has on-hand for delivery. [�Give it to Mikie!!! He�ll eat it.� Erzit �I shot it, you skin it�? <= Can�t remember which metaphor to use. So darn confusing.]

Finally, this issue is NOT limited to SMT parts.

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#20698

SMT COMPONENTS | 15 July, 2002

Ken: Responding to your comments: * If buyers were to communicate better and be more involved with manufacturing, they would make less money. [1] There�d be fewer cases of �Jack� on the home doorstep at Christmas-time. [2] The buyer�s budget would be charged for the cost of repackaging the parts. [3] The time to repackage parts is not built into the production schedule. So, the in-bound material delivery schedule [and by extension the customer delivery schedule] will slip two weeks, if buyer �admits� to approving receipt of mis-packaged parts. [4] There�d be fewer �cost reductions to budget� to talk about at �bonus time�. [Bonus points for doing an admirable job of restraining all hints of cynicism. YES!!!!] * If these packaging faults are such grievous violation of your customer�s procurement specification, why is Receiving Inspection / MRB permitting this defective material get to the production floor and creating downtime? Why don�t they realize that they have a problem until the troops are lined-up, fixed bayonets, and at the ready? Something sounds, if you�ll excuse the expression, fishy.

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Ken Bliss

#20712

SMT COMPONENTS | 16 July, 2002

Hi Dave

I wasn't intending to solve here why all the work is going to China but maybe you have solved part of the puzzle. This problem that I was hoping is isolated it sounds like it is much much bigger, it sounds like the buyers are causing alot of it and the companies they work for are paying the price. The fishy part is what I am trying to figure out, it would seen to me if you have these kind of problems you would be inspecting at the door and not starting production until the issue is resolved. Buying parts in the wrong package makes sense if that is all you can find, but have them repackaged before releasing to production.

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#20715

SMT COMPONENTS | 16 July, 2002

Hey Ken, you open a can of worms, you can�t all of a sudden decide �they�re too slimey�. You gotta fix this one!!! If that means a Chinese visa, we�re behind you this one. {Everyone together now, "Go Ken, go Ken. He's or guy!!!]

The fishy part: Yes, in order to come any level of resolution with this the parts must be MRB�d. * Receiving Inspection must be able to do their job [assuming they know the proper requirements of their job]. [This is tougher to do, if Receiving Inspection reports to Purchasing.] * MRB meets and wants to reject the shipment. * Buyer has to talk the MRB into accepting the parts to maintian the schedule. * MRB reports the action to the BIG boss. * BIG boss sees a pattern and pimp slaps the buyer. [That's the part we like the best.]

Yes, there is nothing wrong with buying the correct part in incorrect packaging. The problem is having production troop standing around looking like lummoxes because they're not geared-up to respond.

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#20716

SMT COMPONENTS | 16 July, 2002

Communication is the issue. What we have here is a failure to communicate....how does that song go? I implemented a system whereby incoming inspection would check component packaging to the spec. If it did not match they were to contact the process engineer to determine if the different packaging could be processed on the SMT line or THT lines. If it could not it was rejected or assembled in a different manner- depending on the customer's delivery needs. If the error was the supplier's fault then they were charged the extra cost "different manner" on assembly. If we could feed the different component package, the P.E. would change the programs and advise the SMT line or THT line supers so by the time the job hit the floor there were no problems and no delay in setup. If the buyer communicated the alternate packaing ahead of time, as they were suppose to, the P.E. took action before the components were delivered to incoming. Communication and having a system that people act on is the key to this "problem". From my years in manufacturing, goin back to 1982, the same "problems" existed. To me its not a "problem". It is a fact of life in manufacturing and you must plan for it.

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Stephen

#20722

SMT COMPONENTS | 16 July, 2002

I worked for a CM in the GTA here in the GWN. Our buyers would give a techie a pile of "part substitutions" for him to sign off on. He would check out the requests and sign only a very small percentage. Some were radically different parts. I asked the buyers about this. I was told the suppliers told them the parts were "drop in" replacements, i.e. same, fit, form and function. An example of the worst would be a DIP16 instead of an SOIC16. An acceptable one would be 4K99 1% for a 5K 5% same size and wattage. Even with so few of the forms getting signed off, "Mama" stopped a lot of things at receiving. So between the two of them and the buyers who were actually good), we didn't see too much wrong stuff reach the floor. Almost all of the wrong package problems we had on the floor were the customers doing things like using SOI16 pads instead of sol16 pads. As for tubes when we wanted tape and reel, we bought a machine to put the parts into tape and reel. And if you search the fine archives you will find a fellow worker of mine posted on that subject. GTA (greater Toronot area) GWN (great white north)

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Rob Fischer

#20732

SMT COMPONENTS | 17 July, 2002

Sounds to me like two different mind sets. Engineers analyze the issue, see a solution and implement it. Buyers get what they can, when they can, and "know" that it isn't an issue, sort of a "they can deal with it" thing. They are also answering to the same, but at the same time, a different master. They hear "we don't want excess inventory and we want things yesterday, oh, and we don't want to pay a lot for it". If they satisfy all three of those requirements they get a pat on the back. Engineers are told "here's the deck, deal with it". I think the solution is to have a common theme throughout the company of feeling the others' pain. Sounds like a fairy tale to me. In my experience the best buyers are the ones who worked on the floor first, kind of like the best sales people. The bottom line is that if the customer doesn't get what he wants, when he wants it, they'll find somebody else to do it. And since the snowball gets bigger as the process nears the end, the one who juggles these anxieties best becomes the one who is most valuable. Having Chinese as a second language doesn't hurt much either...

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Pc

#20803

SMT COMPONENTS | 22 July, 2002

Rob is right on it. The best is when Manufacturing has developed a solid process for a particular build using set component packaging; then, when that build hits the floor later that year for a second run etc.. all odd-forms are in different package types (IC's, D-paks, inductors etc...). Do you think purchasing even takes the time to cross-ref the original parts P.O.? The only time they take is for their fingers to call Digi-key or whoever and order five cents cheaper. You might as well chalk up another NRE cause, at times, this can mean a day of re-programming.

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#20822

SMT COMPONENTS | 23 July, 2002

Ken,

Excellent discussion!!!

I've also seen this problem. Spent and am still spending significant time policing. I don't think it is just a buyer issue though. There are many dimensions to the problem. Suppliers, Engineering, Manufacturing, and Purchasing all play a role. Yes, communication will help, but utimatly management chooses the path of direction. Especially when a schedule is involved. The processes you put in place must be followed. Otherwise, results can be less favorable. Let me share some brief history with my exoerience with this problem and what we've done to resolve:

We traced some excessive attrition rates to specific smt components. The probelm was verified by observing a build in action. After the build we measured the embossed tape cavities and component dimensions for the problem parts and determined the way they were packaged was not conducive for ideal placement. Comparision was made to EIA-481 standard. Talked with the buyer(s) and insisted conformance to EIA-481. (Note: EIA-481 does give suppliers some flexibility) Buyer(s) aggreed to list EIA-481 in PO flow down note codes. Later the vendor responded and claimed they already conformed to EIA-481. For info on EIA-481 see the following URL... http://global.ihs.com/search_res.cfm?customer_id=%21%25K%5D%5C%0A&shopping_cart_id=%27%25X%5B%28J0LLZ%20%20%28%0A&country_code=US&lang_code=ENGL&input_doc_number=EIA%2D481&org_code=EIA

Then asked QA to inspect to EIA-481. Was told by QA Director to pound sand. Too much time and labor would be required to inspect conformance to EIA-481. After escalation to management, the issue abruptly became dead on arrival. Not accepting defeat I started pushing from another angle. Asked for common inventory. The idea was to force Engineering to use common parts (where feasible) across all new products. This in turn would make the buyer's job easier managing component procurement. The result after implmentation was larger part buys thereby eliminating the 'middle man' or distributor, lower part cost, and increased machine capacity. Now we deal directly with component manufacturers. As a result we are now less likely to require a repackage and schedules are not impacted.

We also were seeing an excessive rate of components being place with incorect position or polarity. After an exhasuting investigation I identified several areas of weakness in the process. Here they are:

1. Package media was not specified by Manufacturing. Shame on us. It gave Purchasing an open door to buy anything under the sun.

2. Expected BOM component became obsolete. Those darn Enginese failed to close the loop with Manufacturing on obsolescence. As a result alternate received in different media. Problem not forseen and downtime results.

3. 1st, 2nd, 3rd, and so on suppliers all package differently. Hence when alternates are used package media changes. I found this mostly applies to diodes and transistor suppliers.

4. Matrix trays are not consitently loaded by supplier or distributor. I found that many times we are having to change the orientation of the parts in the tray so our placement machine places the part in the correct postion.

5. Purchasing could order the wrong package media by mistake due to poor communication, or could not get the specfied media order to fit in the lead time.

6. Small incremental buys put us in a bad negotiating position. The result was poor responsiveness and inability to hold vendors to requirements.

7. Distributor/Supplier not aware of EIA-481 standard. The result was incorrect media or loading of the media.

8. Engineering is not consistent with component orientation when creating CAD symbol libraries. The Gerber position files which are extracted from the CAD layout files are used as placment data. If the orienation is not consitent with what's coming in the receiving door the placement program will have to be changed at the time of the first build. Recommend pushing them towards EIA-481 to reduce or alleviate this problem.

I'm sure there are many more possibilities but the point is that unluss you have a process which can either accomodate all the possibilities (unlikely) or you agree to adhear to it you'll never guaranteed success.

If your organization is not buying common inventory try suggesting it. If so try weighing the cost of the attrition, machine downtime, and production delays with the cost of imposing a minimum buy on the parts procured. This may be enough get you out of the hands of the distributors or repackageing houses.

Good Luck, Gregster

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Ken Bliss

#20837

SMT COMPONENTS | 23 July, 2002

Quite an assortment of opinions and problems, I appreciate everyones input. Based on all that I created a process below that seems to me should work well to reduce these problems. There seems to be plenty of blame to go around for everyone in the factory including the suppliers.

With a couple of assumptions in place, i.e. Each employee is willing and knowledgeable to do their jobs at each step.

1. The customer places the order 2. Programming engineering reviews the order BOM for consistency of parts, packaging, orientation for what is standard in the plant. Then identifies what is not per the plant standards. 3. A meeting with the customer, sales, production and program engineering and purchasing occurs to review the non standards and decisions are made of what to change and what to live with. 4. Programming proceeds with programming the job based on those decisions. 5. Purchasing orders all needed parts and gets a schedule when the last part should arrive. If it is a long leadtime purchasing of course should probably pushout the short lead time items to minimize inventory so all the parts arrive within a certain period of time. 6. Purchasing notifies production so they can schedule the start date 7. Engineering gives receiving / inspection the adjusted BOM. 8. Receiving gets the parts in and carefully checks all the incoming parts to be to standards and to ordered spec. ie. right package, right part, right orientation, right ohm. 9. The parts are put into the stockroom. 10. Receiving notifies production that all parts are in and checked. 11. production releases order to start. 12. The necessary empty feeders are pulled and reels are put on them and the setup feeders are staged to go on the machine. 13. The line is changed over to the new job and production begins. 14. The stockroom determines from the BOM what feeders are likely to exhaust during the run and stages those feeders and put them by the pick and place machine for quick changeover. 15. If a problem occurs on the line due to a part problem a work around will have to be determined on the fly. But a process like this should dramatically reduce the problems everyone is describing. Admittedly there will always be unforeseen problems.

It seems to me from all the comments if a process like this were being used consistently that there would be a lot less problems on the line and a lot more uptime. it also seems that if all that happened a typical plant would produce more product in a shift and therefore be more profitable, which would allow the plant to be more competitive with the guys overseas. Somehow everyone in every department needs to learn to work together for the same cause as a team, either company profits are at least to save jobs in the U.S. Both are critical.

Please offer steps that I missed or that should be modified to make more sense. I am very pleased to see the direction this discussion has gone I hope alot of companies are able to use this information from everyone to improve their processes. I plan to show the entire thread to several customers.

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