Validation of Soldering Process - Clause 7.5.2 - my conundrum!

[sbickley]

Hello everyone,

Whew, we just concluded our annual surveillance audit with zero nonconformities - which is a first in my career - very pleased! My question to the forum is about how to apply Clause 7.5.2 to a process such as soldering for PCB repair. Does anyone have suggestions as to how the solder process can be validated? I have worked for board manufacturers in the past, and visual inspection was by and far the most widely used approach, however, it seems that in Cianfrani's book ISO 9001:2000 Explained he refers to soldering process as requiring validation. Help please.

On the other hand, I can see where something like the cross-hatch test that we use in our silkscreen processes would require validation. I am available to add input and answer any questions to help clarify the situation.

Thanks,

 

[BadgerMan]

Here's a good thread:

http://elsmar.com/Forums/showthread.php?t=7965&highlight=solder+special+process

Congrats on your audit results

 

[SRT-4]

This is an interesting question. I have seen Xray testing when some flat pack grid array chips were being replaced on circuit boards because you can't see under it. I think in your case the process gets validated by visual inspection and test combined with operators that have been trained to do the job.

If you want to further validate the process you could cycle/test your board in temperature (-40C to +55C) or carry out vibration. It does get the bugs out if you have a cold solder joint or a part about to give up.

It also depends what your customer is willing to pay. I have seen repair and overhaul contracts on which materiel was critical and burn-in / vibration was requested by the customer after repairs but that was reflected in the contract $$$$$.

 

[Jim Howe]

solder validation

This is an interesting question. I have seen Xray testing when some flat pack grid array chips were being replaced on circuit boards because you can't see under it. I think in your case the process gets validated by visual inspection and test combined with operators that have been trained to do the job.

If you want to further validate the process you could cycle/test your board in temperature (-40C to +55C) or carry out vibration. It does get the bugs out if you have a cold solder joint or a part about to give up.

It also depends what your customer is willing to pay. I have seen repair and overhaul contracts on which materiel was critical and burn-in / vibration was requested by the customer after repairs but that was reflected in the contract $$$$$.

I can recall the x-rays and the visuals and even the certified solder operators with annual eye exams. I also recall the testing. When the first production runs of PCB's for the M1A1 and A2 Abrahms tanks was made the contract always included an FAI/FAT line item. These test were so severe that upon completion the boards were stamped in red "FAT-NOT FOR PRODUCTION" and delivered to training facilities only. Some were even cut up so that a microsection of the pth could be examined.
I am not sure that there is more to the validation process then what has been discussed but if there is I would welcome the info!

 

[qualitygoddess - 2010]

Interestingly, I recently heard of a company that does simple soldering and repair and they did not have to do any significant work for process validation, and it passed their registrar. They calibrate the soldering irons, I think before use. They keep a log that checks the tip temp 3x per day. They have temp ranges on the job travelers, so the operator knows the min and max. This company does certify solder operators.

That's it.

 

[sbickley]

Solder Validation

Thanks to everyone for their responses. We are typically performing very small volume board re-work/repair (maybe 50 boards/month). Therefore, I wanted to keep the validation activities reasonable when compared to the actual work/risk being performed. We have added our solder irons to the calibration program (still need daily checks though), started documenting the functional test and added a simple continuity test and documentation all on the job log. Due to our low volume, we are not going to shell out for the expense of x-ray or AOI technology. Significant re-work jobs go to a local CM that has AOI, visual and Functional Test capabilities. In light of your feedback and our countermeasures I feel comforatble that we can now pass the validation test! Thanks Everyone - that's what this forum is about!

Scott

 

[Raptorwild]

Thanks to everyone for their responses. We are typically performing very small volume board re-work/repair (maybe 50 boards/month). Therefore, I wanted to keep the validation activities reasonable when compared to the actual work/risk being performed. We have added our solder irons to the calibration program (still need daily checks though), started documenting the functional test and added a simple continuity test and documentation all on the job log. Due to our low volume, we are not going to shell out for the expense of x-ray or AOI technology. Significant re-work jobs go to a local CM that has AOI, visual and Functional Test capabilities. In light of your feedback and our countermeasures I feel comforatble that we can now pass the validation test! Thanks Everyone - that's what this forum is about!

Scott

Scott, congrats on your audit! We are also a small OEM, down to 3 people now. We have a log sheet for each work station, which includes testing the ESD safe mat, wrist strap, the ground wire, and the soldering iron (Metcal) for ground. Along with that the soldering iron is tested for temperature, and there is also a place to sign off on treating the mat with anti-static cleaner. The work stations are numbered and the log remains at the work station with the applicable number. We have eye examinations added to our calibration recall system and we give written internal solder, ESD Safe, and Calibration exams anually. We perform functional tests on everything and complete data sheets of the results for all of our products, so part of the validation is: It works!

We have been in business for more than 35 years, and not once have had a reject based on solder defects. We are an AS9100B Registered Company. Keep it simple. Paula

 

[David Hartman]

Data Tracking PCB Assembly/Solder Defects

But, at least loosely related.

For those either with past experience, or currently involved, in electronics manufacturing: What methods/tools are being used to track PCB assembly and/or solder defects (e.g. talley sheets, PC-based data entry, PBA/handheld entry devices, etc.)?

One of the tasks that I have before me is developing the data to determine the nature and severity of our quality problems. I want to implement the least obtrusive methods, but yet ensure that accurate and consice data is returned.

 

[Raptorwild]

But, at least loosely related.

For those either with past experience, or currently involved, in electronics manufacturing: What methods/tools are being used to track PCB assembly and/or solder defects (e.g. talley sheets, PC-based data entry, PBA/handheld entry devices, etc.)?

One of the tasks that I have before me is developing the data to determine the nature and severity of our quality problems. I want to implement the least obtrusive methods, but yet ensure that accurate and consice data is returned.

Hello ddhartma,

I created an excell spread sheet to collect information from our inprocess, receiving and final inspection results. The data is reviewed monthly and during our Management Review meetings which are held twice a year. I developed a set of defect codes for the different kind of discrepantcies, everything from paperwork errors to bad solder joints. The data is entered in one place and automatically updates the annual report and chart. I use this to help calculate our internal PPM. Hope this helps, I will get back to the thread later and maybe post a chart, got to get back to work!

Paula