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

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Wrong Part

#19328

Wrong Part | 29 March, 2002

What are the control process that can be introduce to avoid placing wrong part. We are using machine like Siemens 80S & 80F, Sanyo TCM 3000 and GSM. I am from the Quality System dept.

reply »


CAL

#19329

Wrong Part | 29 March, 2002

Barcode!! The Siemens machines can have bar code Options added.On the Siemens Machines the bar code S/W is a little archaic. In theory You would have a bar code on a reel of part and a barcode on the feeder location (They are the black codes on the side doors).When your feeder runs out you will scan the part then the feeder location for fill (or Vise-versa I cant remember-old age). In theory this sounds great....There are some flaws. Make sure the machine can handle barcodes other than the partnumber (i.e. Lot code, MFG number) because if you have a smart operator they will load the reel of components on the machine and forget to scan the reel so they will scan the empty reel and acknowledge the feeder needing filled.

Essentiality what you are doing is creating a safe guard for operator accountability.Good attentive operators tend not to load the wrong parts(Yes, there are extenuating circumstances). If Incoming inspection accepts the parts (Correct QA info per acceptance sheet) when the operator needs to fill the feeder....the part needing filled is displayed on the screen the operator compares the number on the screen to the number on the reel and if all is correct away you go. If an operator just grabs reels and throws them on the machine.....It is the operators responsibility and should be accountable (Correctly reworking a board full of 0201s with no Mag and with a soldering iron from Radio Shack usually works as a great punishment).

Hope this is a good thought provoking idea.

Steffan Should be able to fill you in more of the Siemens BArcoding.

(There are plenty of ex-Siemens Engineers available- esp after yesterday, to help with the upgrade)

Regards, Cal Manncorp Applications/ product Manager

reply »

#19334

Wrong Part | 30 March, 2002

We are using barcodes but we still end up with wrong parts. Apparently some operators fail to scan the reel. We are pretty strict on this, we even issue 'warning letter' to operator for failing to scan. We see some reduction in wrong parts but not totally eliminated as this control depend on human intervention. Any smart idea?; smarter then the operator or some poka yoke control.

reply »

#19335

Wrong Part | 30 March, 2002

Some earlier machines with mechanical component alignment could be bought with electrical test options ( Mydata, Siemens o.a.). This is, to my knowledge, the only method to identify chip components prior placement. The downside was a high reject rate if the tolerance was set too tight. Quite frequently the option was turned off and not effective. The barcode appears to be the most feasible method. However, it should be more automated. I propose a light barrier switch across the reel container. Whenever a reel has been removed, the machine can only be re-started if the correct barcode is read.

reply »

#19338

Wrong Part | 30 March, 2002

There is three ways to make sure that the component you are about to place is on the correct feeder: 1 Check for the proper component and for the proper feeder location. 2 Check for the proper component and for the proper feeder location. 3 Check for the proper component and for the proper feeder location.

If this doesn't work, the operator making these errors should find his / her life's work in someone else's plant.

reply »

#19346

Wrong Part | 1 April, 2002

Improving the control process may be not top priority of the machine vendors. In the mean time, investigate how the operators make these errors: Are the same part numbers on the reel, or do you have to use the BOM to translate the part number on the reel with the one the machine displays on the monitor? Are the part numbers 110-1156 and 110-1165 right next to each other? Are you re-using the reels and part numbers corrected on the label? Did you get only strips of tape without reels? Use your own imagination, how incorrect part numbers are loaded to the machine.

reply »

Stephen

#19352

Wrong Part | 1 April, 2002

Do you have double "sign-offs"? I.E. two operators look at each reel that gets changed? That helps a lot. One place I worked had labels made up that had the operator put down what the part was and the time and two sets of initials. What I have never figured out is why we would go for months and months without a single mistake then all of a sudden, there would be lots of them in a week. I've seen this at more than one place. When I worked midnight shift, about half the time that we heard that day or afternoon shift put a wrong part on, I would catch one of the midnight operators about to make a mistake. Where I am now, we use lots of dedicated feeders, which reduces the number of reel changes. Therefore the number of chances for a wrong part are reduced. We do 3-8 setups a day.

reply »

Bob

#19354

Wrong Part | 1 April, 2002

One thing to bear in mind when bar coding, make sure that the reel taken off and the new reel being put on is bar coded.

What I have seen previously is that operators bar code the same reel twice, for them it is easier, but does will not always catch mistakes. This sounds obvious, but it is all about education and training and using conscientious operators.

If someone could come up with a 100% way of ensuring the correct reel is always fitted they would become very rich very quick. Please let me know if anyone out there knows of a way

Best of luck.

reply »

#19355

Wrong Part | 1 April, 2002

the good and bad days are normal results of statistics. You enter some variables like number of feeders, length of part numbers, day of the week, sexual satisfaction of the operator a.s.f. , you get some statistical distribution. It tells us that on certain days, we should not refill any components on the machine ( April 1. ).

Fact is, that a machine supplier had a good idea to implement a barcode reading system, but did not complete the functionality. Barcode is a good tool to avoid human errors, as Cal mentioned, but to execute it in a way that you easily forget how it works, makes it a bad tool. And then, where did Siemens find that ancient barcode reader gun. It shoots like a cut off shot gun. Every cashier has a better barcode reader. It is attached to the key board with a spiral cable, but should be working remotely like the ones from SAM�s club. When you read a barcode, you have to tell the machine in which feeder you are about to fill this component. Therefor you read a barcode attached to the machine door, which contains the information of the feeder table location. Because you can not aim, you get a B��p instead of a Beep. You do this a few times and then you find out other tricks to make it Beep. Why is the machine not showing this particular feeder location with a blinking light, laser pointer or at least a picture of the feeder table on the monitor?? This entire barcode thing looks only good in the sales brochure. You are the customer. You bought it. If it does not work you complain. If nobody listens, you have to yell. I think, wrong components are a serious problem and require more attention.

reply »

#19395

Wrong Part | 4 April, 2002

Never can tell which jems you'll find in a search the fine SMTnet Archives, like http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=9426

reply »

Equipment Auction - Eagle Comtronics: Low-Use Electronic Assembly & Machining Facility 2019 Europlacer iineo + Placement Machine  Test & Inspection: Agilent | Tektronix | Mantis Machine Shop: Haas VF3 | Haas SL-20 | Mult. Lathes

Fluid Dispensing Aerospace