Continuing with our discussion on the Original Equipment Manufacturer-Contract Manufacturer (OEM-CM) relationship, it is important to note that, while many contractor operations are similar, they may have very different procedures and methods for mapping workflow.
The OEM can help by anticipating potential problems and segmenting the workflow to ensure a minimum number of line-down incidents. (See: Talking Points in OEM-Contractor Negotiation.)
Most top-level electronic products share some commonality when it comes to the structuring of bills of materials (BOM). This structure is referred to as a "BOM tree," and, depending on the selected manufacturing resource planning (MRP) output format, the entire BOM can be represented as "nested" or "indented."
The lowest level of the assembly is the component level and the unpopulated printed circuit board (PCB). The next level has the stuffed or populated boards, with or without programmed parts. Next level up is the electromechanical assemblies that include mounting hardware, fan brackets, programmed parts, shields, heat sinks, air dams, on-board wire harnesses, and the assembled PCBs.
The top or final assembly usually includes some kind of mechanical housing or enclosure, complete with power supply, wire harnesses, interconnects for points of connections to the outside world, and miscellaneous hardware.
For the purpose of this article, let's assume your model of working with the CM is the consignment version and you are building up to the top level of your product. To facilitate kit and build management, identify and assign a group numbering scheme to the unique assembly structures mentioned above. These groupings are subject to the CM's review -- it may already have an established workflow that involves dedicated work centers with bench inventory determined by each work station's function.
The goal is to segregate major stand-alone assemblies to help identify potential build authorizations and to accommodate time-phased inventory awareness. Instead of identifying particular shortages at the piece-part level, potentially stopping the entire product from moving forward in the linear assembly process, it may be sufficient for the CM to say, "Kit group level 1.3 is not complete." It will then be your call to begin the build knowing that groups 1.1 and 1.2 can proceed as "material complete" while anticipating the timing to fill the shortages for group 1.3.
This will allow time-critical phone conversations without delaying the gathering of detailed knowledge about particular part shortages. The particulars may be determined at a later time and acted upon without incurring unnecessary line-down situations. Below is a suggested breakdown for easy identification of both materials-based issues and also functions or services-based concerns.
Group level 1.1: PCB sub-assembly.
Each board has its own group identifier, 1.1, 1.2, 1.3, etc., including:
Each electromechanical sub-assembly has its own group identifier, 2.1, 2.2, 2.3, etc., including:
All sheet metal and machined parts
Power supply
Fans and blowers
All wire harnesses
All fastener hardware
All cable tie-downs
Loctite adhesive other assembly substances
Group level 3.1: Packaging materials and components.
These include:
Installation Kit (assembled and part number label attached)
Outer shipping carton
Set of end-caps (Left, Right)
Box labels without serial number label attached
Group level 4.1: In-circuit test (ICT), functional test, and burn-in issues.
This call-out is further identified with the assembly to which it applies, including the following:
Parts won't program
Ovens non-operational
Test equipment malfunctions
Software problems
Failed ICT
Examples of service- or function-related call-outs might be:
4.1a/1.1 = Part-programing problem on the motherboard
4.1e/1.3 = Power supply controller failed ICT
By using this method, the entire top-level product is moving via a parallel assembly operation as opposed to a linear, step-by-step arrangement. If there are any shortages detected at the kit audit stage or during assembly due to a high scrap fallout rate, then the unaffected assemblies keep moving forward.
Now your company has a much better system for meeting your delivery schedules as forecasted. There will always be fire drills, but this process of grouping the assembly operations and materials makes the management of those emergencies less harrowing and on-time deliveries more likely.
Douglas, thanks for this post. I did not have an overview of the production assembly but now i have some idea. Your suggestion of grouping the task so that it is easier to identify the shortage and communicate that shortage properly can really work like charm.
This article clearly summarizes how to run a production without getting into to many fire drills. But I didn't clearly understood why the ICT and burnin tests are included in the final package after the complete assembly.
In Circuit Testing, ICT happens post PCB assembly. The functional testing can be at the PCB, Subassembly, or final assembly level. The examples at the end of the article, were for reference only as to how by combining the group ID info, an assembly level and associated problem can be quickly identified and subsequently responded to from a rapid response approach. You can mix and match problem codes, (not all shown) with the various levels of assembly as best makes sense for your product structure and process failure modes. I was able to use this method to keep the line going while part shortages were identified on the non impacted assembly operations underway. CMs have to be meticulous about part audits and process controls and consequently sometime, they will stop an entire operation if anything, anywhere is unexpected. As you may have experienced in a CM line down situation, other customers may slip ahead of you in the queue and that will change the delivery date as originally scheduled. That is what this Grouping ID process is designed to avoid. I apologize for any confusion.
This solution was born out of necessity. When a CM is building a top level product including the shipping materials and packaging, each individual operation requires process-focused attention as there are unique aspects to each operation. By grouping ID names and problems, it avoids miscommunication as to where attention is needed and if there are assigned work centers per operation, a Process or Test Engineer can go to the CM and quickly identify where on the shop floor his/her attention is needed. Thank you for the kind words. It should work like a charm, but it is the adherence to the procedures and good people that make it all work in the end.
I agree with you Barbra. This is very good and inforamtive article. However, even after following all these procedures, we do undergo fire drills on occasions. This is due to extreme speed of project and pressure of time to market. Also managing new concept, design, performance achievement and providing all these required documents to CM on-time is very challenging.
Barb, You always had something to add, even if it was only "well said." Aside from this, though, from your experience, (and theoretically speaking, of course) can a production fire drill really be avoided? By the way, I'll also be asking Douglas the same question.
Douglas, Is it always possible even after following your detailed prescription for a company to completely avoid a fire drill during or after production? And, if it cannot be avoided, what are the essential steps to taking care of a fire emergency?
Radio frequency identification device technology is rapidly gaining interest by assuring the integrity of supply chains through rules-based management.
Machine-to-machine technology is growing so rapidly that one report says there could be 10 billion connected devices by 2016. That's a big market opportunity.
EBN Dialogue enables and encourages you to participate in live chats with notable leaders and luminaries. Not only editors and journalists, but the entire EBN community is able to comment and ask questions. Listed below are upcoming and archived chats.
Archived Dialogues
Thailand Stages a Comeback Join EBN contributor Jennifer Baljko on Thursday August 23, 2012, at 11:00 a.m. EST for a live chat on how electronic manufacturers in Thailand have shored up their supply chain to reduce the impact of future natural disasters.
Euro-Crisis: What It Means for High-Tech Firms Join EBN Editor in Chief Bolaji Ojo and Contributing Editor Jennifer Baljko on Thursday, July 12, at 10:00 a.m. EDT for a Live Chat on high-tech and Europe's economic difficulties.
Microsoft Surface: Potential Winners & Losers What are the implications for the electronics industry supply chain of Microsoft Corp.'s decision to launch its own tablet PC? Join industry veteran and EE Times' systems and OEM expert Rick Merritt on Tuesday, July 3, at 12:00 pm EDT for a Live Chat on this subject.
Join EBN contributor Jennifer Baljko on Thursday August 23, 2012, at 11:00 a.m. EST for a live chat on how electronic manufacturers in Thailand have shored up their supply chain to reduce the impact of future natural disasters.
Peter Drucker famously said "Trying to predict the future is like trying to drive down a country road at night with no lights while looking out the back window." Yet in the razor's-edge world of electronics—with a lean supply chain and just-in-time demands—the need to know the future is vital.
You've heard the saying "the No. 1 supply chain risk is your people." That hasn't always been the case. But today's complex global supply chain requires a new type of multitalented employee. It's one who understands, finance, marketing, economics, is savvy with technology, graceful with relationships and can think analytically.
Where are these people? Are universities properly preparing the next generation supply chain professionals? How do train your existing workforce for these new, demanding positions?
Brian Fuller, editor-in-chief of EBN, will lead a 60-minute Avnet Velocity panel discussion that will ask and answer these and other questions swirling around today's supply-chain talent challenges.
To save this item to your list of favorite EBN content so you can find it later in your Profile page, click the "Save It" button next to the item.
If you found this interesting or useful, please use the links to the services below to share it with other readers. You will need a free account with each service to share an item via that service.
Tweet This