Jump to content
HybridZ

Titanium tubing?


Guest Anonymous

Recommended Posts

Guest Anonymous

Try Burns Stainless. Won't be cheap but they have it (pre-bent pieces even).

 

http://www.burnsstainless.com

 

Also try a local metal supply place if you have any convenient, sometimes they'll have surplus/leftovers they sell quite a bit cheaper. Most likely though, titanium tubing will be special order so don't hold your breath.

 

You could probably avoid welding it using the wide style stainless band clamps, otherwise you're going to have to use a TIG like yo2001 said. On the bright side, you can skip the argon chamber to weld it in since it's not a structural weld.

Link to comment
Share on other sites

Doesn't titanium have a very large growth factor when subjected to heat? I think this causes troubles with mounts in addition to the price. Even mild steel exhaust systems "grow" in length when hot. Make sure you have good mounts that will take into account this factor. The rod in the bushing of new cars works well and is there precisely for this reason.

Link to comment
Share on other sites

I went to the local speed shop the other day, and the guy took me behind the counter to view a 4-cylinder titanium exhaust header. Absolutely beautiful. I went to lift it up and thought I was going to throw it through the ceiling before I got a good grip on it (light!!!). While admiring the craftsmanship and the myriad of colors from the TIG welding heat, I was told the reason the header was there was because it was being sent off to Jet-Hot to be coated. It was too pretty to send off and get coated. Heck, it should have been hung on a wall in a museum. What a work of art.

Link to comment
Share on other sites

Guest Tht1KSguy

Be aware that titanium is some nasty stuff to work with. I remember we tried to recycle some on a project once and they gave us warnings not to cut it with a torch or chopsaw. I guess the fumes are poisonous. I'm also guessing that this would carry over into welding. Side note, we ended up never being able to recycle it b/c there are only 2 places in the country that recycle titanium and they wanted us to smooth cut it into 2ft sections. It was made of about 400 2in pipes 30ft long... do the math how many weeks do you think that would take to cut apart? So we left an unusable $500K chunk of metal lay on the ground.

Link to comment
Share on other sites

The issue with Ti tubing is price and getting it bent. Figure about $100 per pound for 6a4v. Ti also has memory, so you have to overbend it by about 25%. It takes a lot of trial and error with a mandrel bender to get it right. Ti elongation is similar to 304 stainless (about 25%). Ti fumes and dust, like any metal, can be toxic in large quantites, but with adequate ventillation you shouldn't have to worry.

 

Welding it requires purging of the tubes, a big gas lens, a trailing cup behind the TIG torch, and a lot of Argon gas. Any color in the base metal or the weld besides silver or a light straw and the weld is contaminated. Even in a low stress application like an exhaust you will get failure at the point of contamination from carbide precipitation at elevated exhaust temps (over 800 degrees F). Ti and C have an affinity for each other.

 

In use, Ti tubing turns a dark brown, just like stainless, Inconel, and Monel. So, it may look cool when its new, but after about a couple months it will look like most any other header. I suggest you try stabilized 321, 347, or 348 stainless or Inconel. Those are the tubings of choice for lots of high end race cars.

Link to comment
Share on other sites

Try pricing Inconel. A 4' x 8' sheet of .062 Inconel 625 was $1,300 last time I checked. I have no idea what the tubing costs.

 

The newer metals are pretty intersting, but as long as what you're using is stable at typical exhaust gas temps (1,200 to 1,700) then you probably don't need to spend a mint. Unfortunately, at those temps your best "cheap" choice is the 321 stainless James mentions or well coated steel.

Link to comment
Share on other sites

Personaly, if I was to use Ti to loose a little wieght on my car and spend that much dough doing it, then I would malebitchslap.gif and say "heck, I could loose more wieght than that by jogging a couple times a week for free". As for Ti, look at the SR-71 Blackbird. It used Ti panels to make up the plane. These panels were purposely made smaller due to the fact that Ti expands so much. At speed (I think it's top speed was 1,500mph), the panels would expand and seal up the plane from the air friction. While it was on the ground it leaked fuel from between these panels. If you guys want to see some cool metal, check out Zirconium (I think that was the metal shifty.gif ). From what I heard on Paul Harvey's News and Comment, this metal actually shrinks as it heats up! Think about the possibilities with a metal that does this. Now apply your thinking to an engine in a car. Now a F1 race car engine. Hmmm...

 

!M!

Link to comment
Share on other sites

Ti doesn't give off harful fumes when welding or cutting, not in any quantities to be concerned about anyway. Stainless is much worse, with nickel and chromium vapours. Take a torch to Ti though and you will quickly have a white hot fire out of control, (burns like magnesium) which is why it was probably suggested not to use the torch on it. smile.gif

Link to comment
Share on other sites

They also use Zirconium to make fuel rods in nuclear reactors. Hafnium is an excellent neutron absober and is used in Navy reactors as a control rod. Inconel is also the metal of choice for the reactor coolant piping.

 

I think the SR-71 is a full foot longer when at speed. They say the SR-71 airframe will never wear out because it re-temper's itself every time it flies.

Link to comment
Share on other sites

Originally posted by Mat73GNZ:

If you guys want to see some cool metal, check out Zirconium (I think that was the metal shifty.gif ). From what I heard on Paul Harvey's News and Comment, this metal actually shrinks as it heats up! Think about the possibilities with a metal that does this. Now apply your thinking to an engine in a car. Now a F1 race car engine. Hmmm...

 

!M!

Here is a description of Zirconium:

 

"Zirconium is a hard, lustrous, grayish-white metal. The mineral has been known since ancient times, but the existence of elemental zirconium was not known until the late 18th century, It is abundant in S-type stars and is a component of the sun and meteorites. It is very corrosion resistant and is utilized extensively by the chemical industry where corrosive agents are used. Zirconium is routinely found with some level of hafnium, since separation if the two elements is difficult. It is a highly flammable solid and a dust explosion hazard. "

 

;) Doesn't sound like an engine material candidate to me...

Link to comment
Share on other sites

Guest Anonymous

i just read recently in my friend's SCC mag that this guy had an all-titanium exhuast, and titanium tubing used wherever he could. it was for a time attack nissan silvia, and the mag said it took the guy a LONG time and ALOT of money to do it. but since the rest of the car is carbon fiber, i dont think money was a problem for him. i wonder how effective a titanium rollcage would be in stiffening up the chassis. anyone got knowledge on that?

Link to comment
Share on other sites

Guest Anonymous

Wow thanks guys I really did not expect this much response.Anyhow this was just a contemplation thing anyway since I'm thinking about building a new exaust to replace the 2 1/2 setup on the car now.To address the concern some of the other members had,yes i do know how to weld it(theory not practical experience yet)and cutting it with a torch or plasma cutter seems to be a bad idea since the molten TI reacts badly to O2.Acording to Burns Stainless TI tubing in 2in(they don't list 3in)is 33.00 a foot for 18g,304 is 9.50 a foot and 321 runs about 22.64 a foot,so around three times as much as a 304 system and about 30% more than a 321 system.As for bends I was going to pie cut and weld it anyway.Iconel? price not listed so I guess if you have to ask.

 

Thanks for the help

Jason

Link to comment
Share on other sites

Jason. I've doen a bit of Ti welding in the past. Make sure before you start TIGing it you practice. Ti doesn't transfer heat very well, and its quite tricky. Practice practice and you'll save yourself money and time in the long run.

 

I'm assuming you know how to TIG and are planning on back-purging everything as you go. (or chamber weld it) If you've never TIG'd before then I suggest some extensive practice before jumping into something that is $33 a foot!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...