Has anyone tried this on their wankels?

http://www.cryoplus.com/motorsports.html

 

yes... But you must do it on a new or very well rebuilt engine...I did it to the original engine w/ horrible outcome, basically it causes every little imperfection to be amplified, but when i ditched that engine and went with a brand new renesis the freeze works much better....lower engine temps,no worry about breaking anything @10,000 rpm, and it also seems much less noisy

 

I sent them an Email asking a quote on freezing a 13b

 

Got emailed back:

> message:
> Hello! I am wondering about what the cost would be to cyro my whole
13b
> Engine. The weight is about 350lbs, and should only be about 8
pieces.
> Thank you!


----------------------
$625. Plus shipping. It could be shipped UPS if you put it in 6-8
different
boxes. Or are you local?
Thanks,
Kathi Bond




I only said 8 pieces for the 2 housings, 3 irons, 2 rotors and the E-shaft. I dont think it is that bad.

 

Is the weight really 350 pounds for a 13b? I thought it was more like 175-200 pounds.

 

Cant be 350lbs,Ive pulled several 13BT's out of wrecking yard cars with my bare hands....felt more like 250lbs or less, with flywheel and no manifolds/turbo.

 

Cryogenic freezing is a process that is used primarily for steels. I.E. industrial cutting tools that need an incredible level of hardness so that they can continue to do their jobs for extended periods of time. Manufacturing facilities spend LARGE sums of money on cutting tools that go dull after a few uses. If they can double the life of a cutting tool through cyrogenic freezing, then they've eliminated a large portion of their tooling bill.

How does it work? When steel is heat treated it is raised to a certain temperature and then cooled, thus locking the carbon into place. When you raise the temperature you get a composition known as austenite. Austenite is very unstable and will readily change to other structures when it is cooled. This is due to the carbon that is saturating the iron in the steel. However, the outcome of the cooling is dependent upon how long the cooling process takes.

For instance, a slow cooling will give you Pearlite. See below...


A quicker cooling will give you Bainite, a different steel composition...


Finally, the fastest cooling will give you the fabulous composition of martensite...


So at this point you are probably saying to yourself, "So they're gonna heat up my engine and then cool it really fast?" WRONG. They aren't going to heat your engine up, they are just going to subcool it. The steel in any part that has already reached a martensite phase will remain at that phase indefinitely. So if your engine is martensite, then why would they want to heat it up and cool it again to get the same structure of martensite as they had before? However, the lower you cool it below its original temperature, the more martensite you are going to create. See below...

In the vast majority of cases, the extent of reaction is found to be virtually independent of time:

1 − V®0 = exp{¯(MS − T)} where ¯ ' −0.011 (1) V®0

is the fraction of martensite and T is a temperature below MS. This is the Koistinen and Marburger equation; notice that time does not feature in this relation, so that the fraction of martensite depends only on the undercooling below the martensite–start temperature. Thisathermal character is a consequence of very rapid nucleation and growth, so rapid that the time taken can in normal circumstances be neglected. Isothermal martensite is possible when nucleation is hindered, although the growth rate of individual plates of martensite can still be rapid.

So in short, the cyrogenic freezing process is going to take advantage of POTENTIAL martensite that may still be hiding inside the steel's composition. In layman's terms, "Freeze that sucker and see if you can turn any more of it into martensite! She ain't done yet!"

But keep in mind that the cryogenic freezing process is intended to be done on STEEL. Steel is a mixture of Iron and Carbon, and will behave very uniquely when compared to other non-ferrous metals. Personally, I wouldn't bother doing this on the rotary because so little of it is steel. If I'm not mistaken we've got a lot of cast iron, with some aluminum housings sandwiched between. Not much potential to make martensite there, because there ISN'T ANY STEEL TO WORK WITH!

Also, keep in mind that when you cryogenically freeze something while it is going to get harder, it is also going to become MORE BRITTLE. This is the nature of the beast. So while you may get a harder surface, that will last longer, it is also much more prone to catastrophic fractures and failures. You want to retain some of the ductility of the metal to improve its working life.

Is cryogenic freezing good for throwaway cutting tools that are used in machining processes? YOU BET! Is it good for valuable engine parts? I wouldn't recommend it. These are all just my own observations. Hope this has made you think a little more before trying this.

Jamie

 

Looks like the eShaft and gears are the only things that can be cryo treated.

 

Great info Jamie! You've educated us well

 

Yea,Id be worried about that whole fracturing thing, in regards to the E-shaft.
A little high RPM action to the point where the shaft normally starts to whip, and that brittle sucker snaps in half, instead of having the ability to spring a bit and only cost you a housing or rotor.
Sure,the beaing surfaces will never wear out,but hell.....E-shafts last forever anyways.How often do builders get a core engine that doesnt have a usable Eshaft? (in comparison to housings,rotors,ect)