HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
Blogs
Engineering Materials
Aerospace Fasteners Mix It Up
11/8/2012

< Previous   Image 2 of 2   

Alcoa's Keensert inserts and studs, shown here, along with Inconel 718 bolts and standard hexagon nuts, went to Mars on the Curiosity Rover. In spacecraft and aircraft, Keenserts provide high resistance to torque-out and pullout loads.
Alcoa's Keensert inserts and studs, shown here, along with Inconel 718 bolts and standard hexagon nuts, went to Mars on the Curiosity Rover. In spacecraft and aircraft, Keenserts provide high resistance to torque-out and pullout loads.

< Previous   Image 2 of 2   

Return to Article

View Comments: Newest First|Oldest First|Threaded View
Ann R. Thryft
User Rank
Blogger
Re: Aerospace Fasteners
Ann R. Thryft   11/26/2012 12:03:55 PM
NO RATINGS
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.

Cabe Atwell
User Rank
Blogger
Re: Aerospace Fasteners
Cabe Atwell   11/21/2012 4:13:58 PM
NO RATINGS
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.

C

http://usatoday30.usatoday.com/travel/columnist/getline/2005-08-29-ask-the-captain_x.htm

Ann R. Thryft
User Rank
Blogger
Re: Aerospace Fasteners
Ann R. Thryft   11/12/2012 11:56:51 AM
NO RATINGS
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?

bobjengr
User Rank
Platinum
Aerospace Fasteners
bobjengr   11/11/2012 2:38:46 PM
NO RATINGS
 

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. 

Ann R. Thryft
User Rank
Blogger
Re: Where is the picture?
Ann R. Thryft   11/9/2012 12:16:51 PM
NO RATINGS
ttemple, my sources did not divulge the locations of the aircraft assembly photos, probably due to customer NDA requirements. But feel free to guess!

ttemple
User Rank
Platinum
Where is the picture?
ttemple   11/8/2012 3:58:21 PM
NO RATINGS
Ann,

Is that picture from Textron in Nashville?

 

Ann R. Thryft
User Rank
Blogger
Re: Repairs of composites
Ann R. Thryft   11/8/2012 12:31:07 PM
NO RATINGS
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.

TJ McDermott
User Rank
Blogger
Repairs of composites
TJ McDermott   11/8/2012 10:30:47 AM
NO RATINGS
Ann, while composites may cause fewer fasteners to be used in original manufacture, I would expect their use to be undiminished for composite repairs.

Partner Zone
More Blogs from Engineering Materials
A new 3D printer that prints fully functional electronics -- like quadcopters -- will be available later this year from Voxel8, brainchild of Harvard prof Jennifer A. Lewis.
Many of the new adhesives we're featuring in this slideshow are for use in automotive and other transportation applications. The rest of these new products are for a wide variety of applications including aviation, aerospace, electrical motors, electronics, industrial, and semiconductors.
A Columbia University team working on molecular-scale nano-robots with moving parts has run into wear-and-tear issues. They've become the first team to observe in detail and quantify this process, and are devising coping strategies by observing how living cells prevent aging.
Many of the new materials on display at MD&M West were developed to be strong, tough replacements for metal parts in different kinds of medical equipment: IV poles, connectors for medical devices, medical device trays, and torque-applying instruments for orthopedic surgery. Others are made for close contact with patients.
New sensor technology integrates sensors, traces, and electronics into a smart fabric for wearables that measures more dimensions -- force, location, size, twist, bend, stretch, and motion -- and displays data in 3D maps.
Design News Webinar Series
2/25/2015 11:00 a.m. California / 2:00 p.m. New York
12/11/2014 8:00 a.m. California / 11:00 a.m. New York
12/10/2014 8:00 a.m. California / 11:00 a.m. New York
11/19/2014 11:00 a.m. California / 2:00 p.m. New York
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Mar 9 - 13, Implementing Motor Control Designs with MCUs and FPGAs: An Introduction and Update
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  67


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2015 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service