An A380 wing panel is being assembled on this automated line using Electroimpact E4380 automatic drilling and insertion systems for permanent fastener installation. The machines clamp the skin and stringer together, drill holes, insert and form aluminum rivets. They also drill and coldwork holes and then insert titanium pins or lockbolts.
The lightning strike issue isn't about frequency so much as it is about catastrophic results. If you've only got a (for example) 1% chance of something happening, but that something has catastrophic results--people dying, lawsuits--then that's something you've got to protect against, or at least not encourage, in your materials and assembly process selection.
I never thought that lightening strikes on aircraft was so common. I read that it happens 2 times per year on average, per airplane. I have seen electrical discharge responsible for fastener loosening and in some cases, ejecting.
There is a downside to composite pieces, price. Bolting parts together will always be around. I designed a mechanical system that ended up having over 60 bolts.. it was cheaper than with none, that was for sure.
Glad you liked the article. The whole issue of the grounding of composites used in aircraft has been widely misunderstood, so I thought it was a good idea to include some clear discussion on that issue. Could you clarify your question about comparisons between fasteners for composites and fasteners for metal? What sort of comparisons do you have in mind?
Excellent post Ann. I know the longevity of any fastener is dependent upon the application and use. Relative to composite fasteners, do we know how they "stack up" relative to metal fasteners? I have seen no data that tries to correlate life cycles of either type. Great point also about the grounding of composites. I know this must be a huge issue but not talked about too much in the literature.
That's true of course. The question is, given an increase in composite use, whether fasteners will be used in high enough quantities in repair to make up for the lower overall quantities in manufacturing.
BMW has already incorporated more than 10,000 3D-printed parts in the Rolls-Royce Phantom and intends to expand the use of 3D printing in its cars even more in the future. Meanwhile, Daimler has started using additive manufacturing for producing spare parts in Mercedes-Benz Trucks.
SABIC's lightweighting polycarbonate glazing materials have appeared for the first time in a production car: the rear quarter window of Toyota's special edition 86 GRMN sports car, where they're saving 50% of its weight compared to conventional glass.
Design engineers play a big role in selecting both suppliers and materials for their designs. Our most recent Design News Materials Survey says they continue to be highly involved, in some ways even more than the last time we asked to peek inside their cubicles.
Daihatsu is one of the first carmakers to customize car exteriors using 3D printing's mass customization capabilities. Effect Skins -- small exterior bumper and fender panels in different colors and textures -- can be ordered for its Copen convertible.
Several new products in this group of new adhesives, coatings, and sealants are formulated to protect sensitive electronic components, or to seal components of commercial and military aircraft. Others are designed to operate in tough, messy, dirty oil & gas operations, or for rotary applications and motors.
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