minime

iTrader: (11)

Did anyone state they tried using Stage8 bolts?

I use their nuts and they work. The issue is the STUDS.

hustler

iTrader: (6)

Holy ****, you fixed it!!! You're going to make millions!!! Its a shame that we never realized that metal won't stretch when its in bolt-form.

JasonC SBB

Which Resbond are we talking about here?:

And who's tried loosening them afterwards?

http://www.cotronics.com/vo/cotr/pdf/907ts.pdf

neogenesis2004

iTrader: (12)

The stuff from bryan is the RED

TravisR

iTrader: (9)

Talk to this guy, thats the best price I HAVE EVER seen on that material and especially that size with a stud.

I must of not seen it gospeed. I usually check every tip for price.

A286 1800/1325 is perfect. coefficient of thermal expansion is twice what inconel is, its stronger at temperature, lower creep, the whole bit.

neogenesis2004

iTrader: (12)

get me some in m10x15 gospeed. plz?

Savington

iTrader: (31)

Stop saying this, Travis. It's wrong. There are 47 different Inconel/Incoloy alloys, a 5 minute search showed one alloy that has a CTE 50% higher than another Inconel alloy.

Reverend Greg

iTrader: (3)

church!
-g-

TravisR

iTrader: (9)

690 and 706 seem to have the highest CTE as per Online Materials Information Resource - MatWeb with more common alloys right at about normal steel.

A286 starts out at low temperatures with 9.39 and goes to 10.8uin/inF* at high temperature (1500+)
Inconel 690 starts out at low temperature with 7.81 and goes to 9.672 at high temperature (1500+)

690 is also about half the yield strength of A286.

706 is even weaker then 690.

What alloy are you using because I'm not seeing it. Thats the best case scenario for your material selection from that database atleast.

I guess I should clarify here. Given A286's superior physical, and CTE properties, it will tolerate twice to three times the total stretch of 690 or 706 in high temperature given an equal preload.

A286 is actually a stainless steel. Grade 660. SO it expands like a stainless steel. It also has the freak property of a very strong stainless steel at high temperature.

JasonC SBB

gospeed, got 'em in M8 ?

neogenesis2004

iTrader: (12)

Gospeed GO!

minime

iTrader: (11)

LOL, yes Timmeh, we all realize the issue is that metal expands with heat

Sav, what grade of inconel are you going to be testing? What are the specs?

A few I specs I found:

Super Alloy A-286
Mean Coeff Thermal Expansion 9.17
Modulus of Elasticity Tension 29.1

4130 alloy (Stage-8 bolts)
Mean Coeff Thermal Expansion 7
Modulus of Elasticity Tension 29

Super Alloy Inconel 690
Mean Coeff Thermal Expansion 7.8
Modulus of Elasticity Tension 30.6

Reverend Greg

iTrader: (3)

Inconel 690 is the money.Have any of you used any of these materials?Are any of you material engineers?Have any of you spoken to an airframe mechanic?All of the bolts in a jet engine are Inconel(of various alloys)Have you every machined Monel?Then,you are only quessing.
-G-

neogenesis2004

iTrader: (12)

Have you ever dismounted you ***** laden saddle on your high horse?

Savington

iTrader: (31)

I'm not going to say which specific alloy since I don't want to spend $500+ testing this stuff only to have someone find a supplier and go around me.

At 1000F:
Young's modulus ***
CTE ***
Yield strength (.2% offset): ~****

gospeed81

iTrader: (51)

Anything we have is bar stock, and would have to be made.

It would also have to go through heat treat to be worthwhile.

But it can be ordered.

Someone has to pick up the phone and order though...I'd *kinda get in trouble.

gospeed81

iTrader: (51)

Yes, yes, no, sure are, and yes.

Not guessing. My money is on Sav (well, if you insist on holding up a turbo AND sealing the flange with only 4 bolts then my money is on Sav).

But since Travis came out with his top secret material selection I decided to check (as it sounded familiar) and sure enough, we've sent out a few orders of it.

When I'm at work Friday I'll look into it a little more. Regardless, we likely don't just have the size and material we need sitting on a shelf...and even if it was I don't do the five-finger discount thing.

They would have to be made...but I'd tell sales they were full of **** if they wanted $25 a piece for 'em.

TravisR

iTrader: (9)

Want me to go get a scantron and we can go ahead an go at this like real men. 2 men, 2 pencils, 1 test, who will walk away!!!

I think anyone with simple math can look at the numbers and tell which material is superior. Simple simple math, but your still voting on 690 just because?

I have already showed via a time transient computational fluid dynamics model simulated differentials in temperature by which should be consistant with what such a translation in throttle would provoke which would invoke plastic deformation of standard materials.
(The temperature difference causes crappy bolts to break)


I have carefully and dynamically matched this material not to any paticular static condition but over a wide range of transients mathematically such that the worse case scenarios present situations which are not possible and such that its coefficient of thermal expansion matches the joints non-uniform temperature distribution against its non-homogenious bi-material make up to deliver the most consistant preload.
(I found a super expandy metal)

After doing so I computed the stress on the material using its thermal strain and have found A286 to successfully take the load under a determined (by me) preload and referenced these stresses to S/N curves and have determined failure in cycles at max S is nearly off the chart at my properietary preload numbers, and that under this preload the joint will hold any turbo you can fit under the hood.
(I made sure it could hold up to track abuse without your turbo hitting the fender well)

I think I done ok on the engineering side of it. How did you determine which material was the best. Pick a tiger by the toe?

Reverend Greg

iTrader: (3)

I dont understand what Ive just read,Use a comma every now and then.Ive done 75 destructive tests on 5 differnt Inco materials,I put my hands on them.Have you?Ive researched this for 6months(in 2003),have you?I graduated with a degree in Materials Technology from New mexico state.I have REAL world experiece,You used Cosmos.Half of what you said was double Talk,I dont have to give condecending remarks in (),Everyone understands what Im saying ,because I understand what Im saying.CTE is not going to give you a real world indication as to what is going to happen when your stud is cycled(75* to 1200*).it will get big then get small,who cares.Tensile strength will,what part of the bolt is PERMANENTLY deformed causing it to be longer?It didnt get small again,it elongated in TENSION.Take a bolt heat it to 1200*,pull it till it breaks,Tensile strength.Do a real test,CFD does not take in to account for alloy NC or convection.I did tests on materials of all alloy(not just Nickel).I think that 690 would be the best choice because a 1" welded rod "coupon" withstood 110,000 psi. in two tests.It sounded like a bomb going off,when it broke, 1/2 above the weld.Thats how I made my decision.-G-

Reverend Greg

iTrader: (3)

hey I will pm my address why dont you come and help me get down big boy.
-G-