A non-aerospace customer's board was repaired without authorization. Does an IPC document state that customer approval is required for class 3 repairs? The Assembly Brothers, Phil Zarrow and Jim Hall, answer this question. Board Talk
Board Talk is presented by Phil Zarrow and Jim Hall of ITM Consulting.
With over 35 years experience in PCB assembly, Phil is one of the leading experts in SMT process failure analysis.
He has vast experience in SMT equipment, materials and processes.
A Lean Six-Sigma Master Blackbelt, Jim has a wealth of knowledge in soldering, thermal technology, equipment and process basics.
He is a pioneer in the science of reflow.
And welcome to Board Talk with Phil Zarrow and Jim Hall of ITM Consulting, the Assembly Brothers.
We're here to talk about electronic assembly, materials, equipment, components, practices and procedures, among many other things. Jim, what is today's question?
Well, it comes from S.L. We have a case where a non-aerospace customer's board was repaired without prior authorization. It was for a class 3 assembly.
The question is does it specify in an IPC document that customer approval is required for class 3 repairs?
Let's go look to the holy scriptures of IPC for all of the answers to life and the meaning thereof. Most likely not.
Because this would be the type of thing that would be somewhat contractual, and I would also say application specific in terms of how much repair should be allowed.
But the whole idea of whether it is allowed or not that is basically between the customer and whoever is building the board and what is agreed upon.
Don't keep going to the IPC or the SMTA or the IEEE or who knows what, the AFLCIO to look for regulations for everything.
This is something that would be agreed upon, based on the type of components you are dealing with, how much repair rework should be allowed for those.
There may be some indication in that, some of the specifications or recommendations.
But in general it is basically agreed and it is driven by the application and the service and reliability expectations of that particular application.
I'm not the world's greatest expert on IPC specs, but I agree that I don't believe they get into defining change of authorization and things like that.
They define what you need to do, how you communicate it, how you may document it, and so forth. And I agree with you I don't think that they should.
It should be decided by the parties involved.
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As a supplier quality engineer, I've learned that repair permissions have to be defined up front in the Statement of Work or other quality agreements or contracts. IPC 7711/12 has a lot of rework procedures and some of them can be pretty sketchy for high reliability and aerospace applications. These include wire adds and pad repair. Both of which I highly recommend against for class 3 applications for many reasons. Wire adds can create parasitic antenna's for example. Pad repairs can fail under temperature fluctuation. If the customer doesn't ask, the supplier should always be very careful to ask what type of rework is allowed. In the event of an aircraft failure in flight, it could ground the aircraft or worse! Lots of FAA officials can ask a lot of questions that better have solid answers or the liability of doing rework will have consequences. Another thing to think about is how many rework cycles or operations are allowed. I had a supplier once rework boards so many time
As the via's started to fail, resin voids and other issues can crop up after repeated rework cycles. The type of laminate and the design play into how reliable the board remains after repeated temperature excursions. A good rule of thumb is to allow touch up of joints for insufficient solder. I allow them to fix tombstones and such and any other rework such as BGA removal is required to get authorization. Also, the equipment and process should be reviewed to ensure consistent results without damage to the PCB. I use microsections to ensure no damage occurs to validate the process.
Bradley J Fern, Entrust Datacard
I have yet to work on a Class 3 project where there was not a formal master contractual agreement that governed all other specifications. If such an agreement does not exist I would recommend developing one with your customer.
Dave Schaefer, DJS Design
Under IPC or J STD. The assemblies can be reworked/repaired. This question should all ways be clear in the contract and quote. If the RFQ doesn't call it out I would add a note stating rework/repairs will be conducted under the workmanship standard.
Totally agree. Repair method is agreed between customer and contractor. By the way, anyone know where I can get a job like Stadem's where I can exercise my ego by reciting IPC specs all day?
M Mota, MET
Yes indeed the IPC/J-STD-001 states that for class 3 products the customer has to approve of repairs. But like the commenters said before there is a difference between repair and rework, so make sure you do understand the difference. The criteria on rework are quite different.
Furthermore if J-STD-001 is not specified in the contract then it is not applicable, so then it depends on how the contract is made. F.i. it could be that repairs are excluded by the customer anyway (and even rework for that matter). So you can not answer this with yes or no. It depends on how the contract is laid out and what IPC documents apply for this product.
Frank Huijsmans, PIEK I.E.C
I think there needs to be some clarification. They said it was and end user board that was repaired. Was in WIP or was it a return? If it was WIP then it could be rework and not repair. If it was return then definitely repair and even if not required for a class 3 customer I would notify them.
Earl Plotner, Cinch
The simplest way to address such questions is to realise that IPC specifies mechanism, not policy. In other words, IPC standards do not dictate whether repairs or rework are allowed, but do dictate how they are to be done and documented.
Donald H Locker, Pi Innovo, LLC
Such requirements are Quality Management Requirements and you can have these in the AS9100 standard, if the product is for aerospace or mil end-use.
The organization shall not use dispositions of use-as-is or repair, unless specifically authorized by the customer, if the nonconformity results in a departure from the contract requirements.
You might also probably find similar rules in customer quality requirements or other QMS standards dedicated to high reliability products.
Christophe Auburtin, FEDD
From IPC 7711/7721. Highlights are mine. I hope this answers your questions.
1.2.2 Requirements Flowdown
The applicable requirements of this document must be imposed by each manufacturer or supplier on all applicable subcontracts and purchase orders. The manufacturer or supplier must not impose or allow any variation from these requirements on subcontracts or purchase orders other than those that have been approved by the user. Unless otherwise specified, the requirements of this document are not imposed on the procurement of off the shelf assemblies or subassemblies. However, the manufacturer of these items may comply as deemed appropriate.
The user of the product is responsible for identifying the Class of Product. The procedure selected for action to be taken (modification, rework, repair, overhaul etc.) must be consistent with the Class identified by the user. The three Classes of Product are:
1. Class 1 - General Electronic Products Includes products for applications where the major requirement is the function of the completed assembly.
2. Class 2 - Dedicated Service Electronic Products Includes products where continued performance and extended life is required, and for which uninterrupted service is desired but not critical. Typically, the end use environment would not cause failures.
3. Class 3 - High Performance Electronic Products Includes products where continued performance or performance-on-demand is critical. Equipment downtime cannot be tolerated, end-use environment may be uncommonly harsh, and the equipment must function where required, such as life support and other critical systems.
The act of restoring the functional capability of a defective article in a manner that precludes compliance of the article with applicable drawings or specifications. Repairs are generally changes to an unacceptable end product to make it acceptable in accordance with original functional requirements. The control of repaired products should be by means of Material Review Board (MRB), or its equivalent, which may consist of
Design Engineering, Quality Assurance, and User representatives.
The MRB, with technical support, should define the mutually acceptable repair method to be used and take the action necessary to ensure that all applicable procedures are adhered to. Repair of a failure in the field seldom includes an MRB, and typically is done in accordance with a contract, repair/service order or the user-activity maintenance program requirements. The maximum number of repairs per printed wiring board assembly should be
determined by the using activity or agency.
1.7 Basic Considerations
1. Appropriate Approvals Appropriate approvals should be obtained before proceeding with PC board modification, rework or repair. Such approvals should include agreements as to acceptance criteria and limitations.
Richard Stadem, General Dynamics Mission Systems, USA
I agree that this is dependent on contractual requirements, but IPC does address this issue. From J-STD-001F, Section 13.2 Repair, Repair is the act of restoring the functional capability of a defective article in a manner that does not assure compliance of the article with applicable drawings or specifications. A hardware defect shall not [N1D2D3] be repaired until the discrepancy has been documented. The repair method shall [N1D2D3] be determined by agreement between the Manufacturer and the User. Customer approval is required for repair if J-STD-001 is part of the contract.
Kenneth Robinson, Lockheed Martin, USA
J-STD-001F section 13 rework and repair; clause 13.2 states, "Repair is the act of restoring the functional capability of a defective article in a manner that does not assure compliance of the article with applicable drawings or specifications. A hardware defect shall not be repaired until the discrepancy has been documented. The repair method shall be determined by agreement between the Manufacturer and the User. This is required for Class 3.
Guy Ramsey, RDIS, USA
Yes IPC-J-STD-001E and F version specified that repair method shall [If not Defect for class 2 and 3] be determined by agreement between the Manufacturer and the User. See 13.2. Watch out different between Repair and Rework.