A aviation & planes forum. AviationBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AviationBanter forum » rec.aviation newsgroups » Home Built
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

steel 4130



 
 
Thread Tools Display Modes
  #1  
Old October 17th 03, 09:01 AM
Philippe Vessaire
external usenet poster
 
Posts: n/a
Default steel 4130

Hello,

when I read 90,000 lb/sqi for strength,
is it just before the part is broken or is it the elastic limit?

Thanks
--
Philippe Vessaire Ò¿Ó¬

  #2  
Old October 17th 03, 03:46 PM
Cam
external usenet poster
 
Posts: n/a
Default

That would be UTS , ultimate tensile strenght. I think yeild
strength is at what point the material starts stretching.

Personally, I've had a problem with numbers, so i tend to
do destructive testing with a pull ram and a pressure gauge. As far as
chromolly steel goes, it seems to "snap"
right at the point of stretching. So I'd imagine its Yeild Strength is very
close to its UTS .

If you see two numbers for strength, pick the lesser one and halve it , and
design from that .

Cheers (no qualifications) Cam...


when I read 90,000 lb/sqi for strength,
is it just before the part is broken or is it the elastic limit?

Thanks
--
Philippe Vessaire Ò¿Ó¬



  #3  
Old October 17th 03, 06:00 PM
Paul Lee
external usenet poster
 
Posts: n/a
Default

Wicks aircraft catalog gives two values for 4130:
min tensile (breaking) 95,000 and min yield (where it starts
distorting) 75,000. Usually the initial yielding will have quite
a bit of strength giving you a chance to get back down. But
repeated cycles will weaken it and rupture. Check the structure
for any cracks and fix it.

----------------------------------------------------
Paul Lee, SQ2000 canard project: www.abri.com/sq2000

Philippe Vessaire wrote in message -moi...
Hello,

when I read 90,000 lb/sqi for strength,
is it just before the part is broken or is it the elastic limit?

Thanks

  #4  
Old October 17th 03, 08:28 PM
O-ring Seals
external usenet poster
 
Posts: n/a
Default

On Sat, 18 Oct 2003 03:46:35 +1300, "Cam" wrote:

That would be UTS , ultimate tensile strenght. I think yeild
strength is at what point the material starts stretching.

Personally, I've had a problem with numbers, so i tend to
do destructive testing with a pull ram and a pressure gauge. As far as
chromolly steel goes, it seems to "snap"
right at the point of stretching. So I'd imagine its Yeild Strength is very
close to its UTS .

If you see two numbers for strength, pick the lesser one and halve it , and
design from that .

Cheers (no qualifications) Cam...


Cam,

While that might sound like a good (and conservative) approach to the
design, he probably wants to build something that will be able to get
off the ground. If your suggested technique were to be used
throughout the aircraft, it would probably be too heavy to fly.

O-(some qualifications)Ring
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Welding techniques for 4130? Building The Perfect Beast Home Built 29 September 4th 03 08:52 PM
4130 frame? Steve Thomas Home Built 23 August 27th 03 05:50 PM


All times are GMT +1. The time now is 05:58 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AviationBanter.
The comments are property of their posters.