A client approached us with a problem they were facing when shipping backplane connectors to their overseas assembly operation. These connectors were a straddle-mount plug variety with 240 extremely delicate legs or pins that were bending in transit even while packaged in a protective tube. Leads were bending sideways, forwards/backwards, and being crushed down. A backplane is known as the motherboard on a PC and simply the backplane rack (the spine) of large rack-mounted systems. The end-customer for this application is a maker of in-circuit test equipment. The piece itself is a very mature product in its end-of-life. Production has been phased out. Our client purchased about 5,000 pieces to hold them over for five years while a replacement is designed into their product. The connectors come 6 to a tube with 12 tubes to a master carton. Their stockroom is in MA with their EMS provider located in Nantong, China, (50 miles NW of Shanghai). The main problem is that in shipping, the parts are subject to "shock and vibe" which dislodges the small black high durometer rubber spacer that subsequently damages the pins of each connector. Each connector is attached to the printed circuit board by two "outrigger arms" using screw mount assembly. After careful review, the client ascertained that these connectors were shifting during shipment allowing one unit's outrigger arm to slide into the next unit's legs/pins causing damage. Upon further review, the spacers used for containment were found to be too small enabling them to shift and float away from their fixed position in the tubes.
OX3 was brought in to evaluate the situation and devise a series of steps to mitigate the damage. Our team came up with a series of steps, as follows:
- Receive the known-bad units.
- Open the box and remove the bags.
- Remove the tubes from each bag.
- Keep a copy of the old bag label with each tube to ensure lot/date code integrity.
- Place each tube on the work table with leads orientated in the up position.
- Remove the paper seal sticker on End (A) of the tube and discard.
- Take out the sponge on Tube End (A).
- Carefully, slide all units and all spacers out from Tube End (A) of the tube without damaging the leads.
- Inspect units for damaged leads.
- Set aside all damaged units.
- Take off the seal sticker on Tube End (B) of the tube and discard.
- Replace a new Black End Plug Tube End (B).
- Reseal Tube End (B) with a new paper seal sticker.
- Load known-good units back into tubes separated by Spacers.
- For short tubes, (not all 6 units were known-good), hold until more units are supplied by customer.
- Hold the final short tube aside in the Holding Pen.
- Do not fill in with units from different boxes until approved by customer.
- Finish with a Black End Plug, and Paper Seal Sticker at Tube End (A).
- The end result will have six connectors, five spacers and two end plugs.
- Insert 5 completed tubes into a new bag with desiccant pack and humidity indicator card.
- Vacuum seal each new bag.
- Apply new label while also taping old bag label onto each new bag.
- Hand record the number of Known-Good units onto the old bag label.
- The tubes themselves are not lot-traceable. The box however is lot controlled.
- Individual Straddle Mount Plugs are date-coded.
- Place all units into their original (old) shipping box
- Known-good units will be in their tubes.
- Damaged units will be segregated but still enclosed in a dry-pack bag and boxed.
- Final count must always total 150 units, (6 units per tube, 5 tubes per box, 5 boxes per carton) plus any damaged units.
- Mark the outgoing carton with quantities of units, (known-good + damaged = 150).
In time, OX3’s client’s complete stock of straddle-mount backplane connectors were culled of bad units and repackaged for secure shipment overseas.
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