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Glenn Butcher
15th April 2003, 09:54 PM
Hi there, I found this on another site:

Ceramic Apex Seals

Here is some information for you on the ceramic apex seals that are being produced.

The quality of this material can only be described in one way. No expense has been spared, only the best, the toughest, high temperature ceramic was chosen (gray material).

This product is made with the highest quality material that can withstand temperatures of up to 1400 ºC under continuous use and its’ fracture toughness is fantastic. The material is tested for thermal shock capability by heating it to 1100 ºC then dropping it into a pail of 20ºC water, without breakage. It has been said that no one has been able to thermal shock this material into breaking, i.e. it should be ideal for nitrous. The seals will be machined with 0.0055" overall clearance. Growth of the seal (13B) has been calculated at 420 ºC and is under 0.004". Remember it takes a lot more than 420 ºC to get the ceramic that hot. A second ceramic material (black material) is also offered. This is an automotive grade ceramic used to make intake/exhaust valves, ball bearings etc. This is an excellent material that is very tough and resistant to chipping. So far it has been tested at 15 Lbs boost with great success and I suspect it will handle a good deal more. Thermal shock testing for this material is somewhat lower at 600 ºC without breakage. Growth is somewhat less than the premium material at a given temperature.

Types that will be stocked are, 1 piece 3mm 13B, 2 piece 3mm 13B, 2 piece 2mm 13B and 2 piece 12A seals in both grey and black materials. Three-piece seals will not be made at this time.

The 13B seals have an overall length of 3.1445" +0.0005" -0.000". So there will be a clearance of 0.0055" (0.1mm) +0.0005" (0.0125mm) -0.000"/mm with respect to a dimensionally perfect housing (3.150”). Generally even new Rotor Housings are 0.001” to 0.0015” under the perfect dimension, therefore a housing that is 0.0015” under will still have 0.004” overall clearance (ample for high boost applications). The 12A seals have an overall length of 2.7525” +0.00” –0.0005”. Additional clearance is required for 12A turbocharged engines.

It is possible to customize seal lengths based on accurate measurements of the rotor housings, minimum thickness area. This will be somewhat more expensive due to additional set-up on a small quantity, however it is highly recommended when using large amounts of boost due to the increased heat.

Why ceramics?

Technology has advanced in leaps and bounds over the last 10-15 years. No longer is steel the strongest or first choice for today’s high tech applications. Advanced ceramics have made their way into many Aerospace, Oilfield and Automotive applications with astounding success and now they are available to you in the form of a “SUPER” Apex Seal. Stronger than steel, lighter than steel, less abrasive than steel, less friction, negligible wear, reduced rotating mass, housing friendly and almost unbreakable (save for detonation or engine failure). Is there any other choice?

Application:

Mild to wild, street to strip, when you want to go fast and you want your motor to last, ceramics is the only way to go. Whatever your Porting pleasure, Nitrous or Turbo Charging requirements, there are “NO RULES”, a seal is available for your application.

Similar ceramic seals have stood up to 40 Lbs + boost with a properly tuned engine.

GRAY MATERIAL BLACK MATERIAL

Aspirated- all applications Aspirated- all applications

Turbo- 40+ Lbs boost Turbo- up to 20 Lbs boost

Max Temp Use- 1400 ºC Max Temp Use- 1150 ºC

Thermal Shock Parameter- Thermal Shock Parameter-

1100 ºC 600 ºC


Fracture Toughness- Growth- slightly less than gray

25% higher than black material material


Process:

· Machined as non-aggressively as possible ensuring minimal damage to the ceramic seal surface.

· Machined with longitudinal striations (machining lines) where possible, maintaining maximum fracture toughness in all directions.

· Tested for fractural imperfections using a level 4 Fluorescent dye-penetrant (used in nuclear testing applications, see attached photos). Procedure in accordance with ASTM 165 liquid penetrant inspection method. AITEC quality assurance manual ISO 9002: 1994. Personnel qualified by independent examination to: Can/CGSB II 48.9712 2000, ISO 9712, which is equivalent to the American standard: ACCP, ASTN (American Society For Non-Destructive Testing) Central Certification Program. Microscope inspection follows if necessary.

· Upon completion of inspection are exposed to an oxidizing atmosphere, which oxidizes the surface resulting in increased strength by reducing stress incurred in machining. This process reduces sharp edges slightly and gives a super smooth surface with a cloudy or milky appearance rather than a glass like appearance.


Specifications

Length- (13B) 3.1445” +0.0005” –0.000”

(12A) 2.7525” +0.000” –0.0005”

Height- 0.0360” +0.000” -0.002” to outer spring step

Thickness- (3mm) 0.1155” +0.0005” -0.000”

(2mm) 0.0076” +0.0005” –0.000”

Weight- under 6 grams per piece (3mm 13B)

Outer spring length- stock 3mm 13B

Inner spring length- stock 12A or 13B cut to 12A length

2mm springs are 3mm springs modified to 2mm width

Custom spring kits will be available in the future


Pricing is in American Dollars and is as follows:

Premium (gray material) one-piece seals. Suggested Retail $1195.00 USD.

Premium (gray material) two-piece seals. Suggested Retail $1795.00USD.

Excellent (black material) one-piece seals. Suggested Retail $995.00 USD.

Excellent (black material) two-piece seals. Suggested Retail $1495.00USD.

Springs are not included in the above prices.

maximtaylor
16th April 2003, 10:08 AM
Yum yum Glenn

They really seem to be the business on paper and combine high strength with low friction.

Now all they need is to become affordable, but as with most technologies I imagine this will happen eventually!

Regards

Max

bill shurvinton
17th April 2003, 11:07 AM
Interesting. Is that price per set?

I would be interested in having a try of those on a NA bridge port I am planning at some stage, but I notice there is no mention of RPM limit :-(

Bill

Fish
17th April 2003, 11:31 AM
Max, Bryan Ellis came across these a little while ago. He passed the information on these to Carl last week, and spoke to him at Brooklands. I can only hope that Carl thinks that they are worth trying, as they come in cheaper than the Ianetti seals.

Dan

Carl
17th April 2003, 11:57 AM
I am willing to try them in anyones engine if they are willing to take the risk!
Seriously though I believe that Pip at WGT has put them in to customers engines(maybe race)so if you want to know more then give him a call.
Regards
Carl

Glenn Butcher
17th April 2003, 12:14 PM
Hi Carl,

I think Gary Gooding has these seals in his engine - but I believe they came from Malaysia?

The company is RSR Rotorsports in Canada I think.

catboy
17th April 2003, 02:58 PM
I worked with high purity ceramics for a couple of years in the US, and I wonder what these are like in rotary applications... ...I know they have been used with sucess, but the fracture strenght of ind. ceramics (maleability) is awful... ...I would have thought that a sieze with ceramic apex seals would have some pretty devestational results on the rest of the engine!...

also some ceramics are v.abrasive... ...anyone know what sort of wear these seals cause on the rotor housings?

b :)

bnaellis
5th May 2003, 08:55 PM
Hi all,
Some latest info on the nrs ceramic seals pasted below.


NRS Rotorsports ceramic seal test results
Here is what Jeff McCall had to say about the 1 piece 3mm 13B Black seals that he tested.

Rotary Power
18111 Harvard Blvd.
Gardena, Ca. 90248
(310) 516-9959

N.R.S. Rotor Sports
Edmonton, Alberta


Dear Sven Nielsen,
The Ceramic Apex Seals were installed in a 1987 13B Turbo. This vehicle is used as a commuter vehicle, which commutes 60 to 70 miles a day, 5 day a week.
Under street conditions, we broke in the seals for 744 miles.
Our first test on the seals was at The Streets of Willow Road Race coarse, in California. We ran 10 hard laps at 15 psi of boost, on 91-octane fuel. The temperature at the track was 106 degrees Fahrenheit.
The next test was at 1200 miles. We took it to LA County Raceway for a weekend of drag racing. The seals held up through the abuse of 20 passes on a Œ mile track.
At 3600 miles we did high speed testing. We ran in 5th gear at 7100 rpm for about 5 miles.
After more commuting and several speed contests with other cars. The engine detonated, which broke two Ceramic seals, a side seal and the rear iron at the dowel pin. To our surprise, the housings survived. After replacing the seals with steel apex seals, which broke after only 500 miles, we found out that it was a wiring problem. Which we determined was there from the beginning. Meaning, your seals lasted 3600 miles with a wiring problem and the steel seals only lasted for 500 miles.
If it wasn’t for the problem, we believe that the seals would have lasted through a lot more of our abuse. It is a shame that our testing of your seals was cut short by a wiring problem, but as they say, “That’s racing.”
I believe that the quality of machining and the tolerances held, rival any Ceramic seals on the market.
Sincerely,
Jeff McCall

Rx7-AIII
6th May 2003, 06:14 AM
Anyone interested in a GB?
1 piece 3mm premium seals

Hi

Thanks for your interest in my product. The price for 1 set (6 pieces) is $1195.00 USD. The price for 5 or more sets is $849.00 USD per set (6 pieces). Therefore for your 6 sets (36 pieces) is $5094.00 USD. Shipping is F.O.B. Edmonton, Alberta, Canada. Please send me your email address and I will send you the information package, which includes shipping and payment information. I can ship them by UPS prepaid if you do not have an account with a courier. The additional cost for 2 day service would be $40.00 USD, brokerage charges included. Please call or email me if you need any more information or payment options.

Thank you,
Sven Nielsen
NRS Rotorsports
10424-75 Street
Edmonton, Alberta Canada T6A 2Z5
780-468-2567
nrsrotorsports@shaw.ca

bnaellis
6th May 2003, 09:43 AM
Hi Sven,
You sent me some info on these ceramic seals a little while back. I am definetly interested in trying a set of these when it's time for a rebuild. I only have 34,000 miles on the clock at the moment so maybe a little while off yet.

Regards

Glenn Butcher
6th May 2003, 10:05 AM
Hi Sven!

Thanks for joining the Forum and posting this information here, please feel free to add this info. into a new section of the Forum that I created in the "Club Classifieds" section --> "Rotary Vendors".

Hopefully we will get some business over your way.


Originally posted by Rx7-AIII
Anyone interested in a GB?
1 piece 3mm premium seals

Hi

Thanks for your interest in my product. The price for 1 set (6 pieces) is $1195.00 USD. The price for 5 or more sets is $849.00 USD per set (6 pieces). Therefore for your 6 sets (36 pieces) is $5094.00 USD. Shipping is F.O.B. Edmonton, Alberta, Canada. Please send me your email address and I will send you the information package, which includes shipping and payment information. I can ship them by UPS prepaid if you do not have an account with a courier. The additional cost for 2 day service would be $40.00 USD, brokerage charges included. Please call or email me if you need any more information or payment options.

Thank you,
Sven Nielsen
NRS Rotorsports
10424-75 Street
Edmonton, Alberta Canada T6A 2Z5
780-468-2567
nrsrotorsports@shaw.ca

Rx7-AIII
6th May 2003, 03:20 PM
Hi Guys
Sorry Sven didn't join the forum.
Martin Sintler

Rx7-AIII
6th May 2003, 03:21 PM
These are the seals that Glenn put the info up about at the start of the thread.

Glenn Butcher
6th May 2003, 03:23 PM
Hi Martin,

I thought you were Sven! :)

.ps When you get a chance - update your signature in the User Control Panel.

Herblenny
30th May 2003, 09:28 PM
Hi know I'm not an expert in Seals..

What I know of the history of Rotory engine is that Mazda was working to reduce the chattering of the housing.. and final apex seal was the combination of material that reduce the chattering the most..

Its like the Hurley seals.. Some initially thought they were great because it will hold higher boost and more.. but at the end, when it went, it took everything with it.. So, when your engine blew, you couldn't reuse housings, rotors, and did horrific damage to the turbos as it when out of exhaust... I would think that ceramic would be too rigid and have too much pores. But could be wrong..

bill shurvinton
30th May 2003, 10:11 PM
So how come the mazda 767 which won at le mans and produced nearly 700HP from a NA 4-rotor not only used ceramic apex seals, but ceramic coated rotor housings as well?


As an aside on the hurley seals, I know people in the USA running huge boost on the 3mm seals with no problems. But if one does go it neither harms housing nor turbo, which cannot generally be said for the factory steel ones. In fact until very recently when there was a quality control problem a large number fo the big HP engine builders recommended hurley for that reason. If a seal goes a rebuild takes less than an hour ( NB this is a race engine).

Carl
31st May 2003, 05:00 AM
In My opinion it very much depends how the seals go wrong in an engine as sometimes even Mazda seals just crack but do not disintigrate and then the housings and turbo are ok.Whoever say's that Hurley seals do not do any damage when they break has not seen what I have seen.Even the Mazda carbon seals sometimes do damage the housings on naturally aspirated engines,and they are much less likely to than any other seal out there.
It makes sense to me that rather than put in a weaker seal, in case of when it goes wrong it causes less damage, it is better to put in the best possible seals ie:ceramic, to try to prevent the possibility of the failure in the first place.
Anyway if the engine is setup properly with fueling and the like it should run happily for a long time,usually the poor old apex seal gets blamed for something that was caused by a poor setup externaly that causes the internal failure on the part under most stress, which is the apex seal.
Hope this info is useful.
ps the ceramic apex seals are stronger,lighter and lower in friction so can have higher spring pressure than any other seal which means that they stay on the rotor housing at revs and prevent preignition from happening.Heavy steel seals are prone to skipping on the minor axis and do not contain compreession at revs so well.
All of this does not mean that in some applications that Hurleys are not ok,just have diffrent problems that need to be taken into account.
Remember,there is no such thing as the perfect seal.
Regards
Carl

Iwan
3rd June 2003, 06:34 AM
OK... here I go with my broken english ;)

so far, it was interessting to read all the posts.

First what I would like to ask is, in which process the seals was made?
Ceramic seals are nothing new. NSU/Audi was running engines with ceramic in early '80s. The seals was not hole ceramic, there was coated in CVD process. Also the engine housing where also coated like the 787 LeMans engine.
So the next question is, of which material are the seals coated? Only Si3N4 (or Siliciumnitrid) is right, anything else will not work right.
another question is, which seals are used for coating? The best is, to take the stock 2 peace seals and coat it with about 0,05mm of Si3N4. One peace seals are not recomendet, but will work. I have never seen 3 peace ceramic seals.
They are new processes for ceramic coating just in test by Frauenhofer Insitut in Germany. The new process will coat in Plasma irradiated process. This is realy interessting thing, but with this technology you can coat only in 0,06mm which is to thick. Diamond grind together with this new process are tested now. I will get the price for this new coating process within next days. If the price is right, I will coat my seals and housing.

Regards
Iwan

Carl
3rd June 2003, 07:52 AM
Hi Iwan,
Nice to get your thoughts.
The Iannetti apex seals are not a coating but solid ceramic which are formed and then machined to size and shape.
They were developed in the mid to late 1980's by Francesco Iannetti,and the design now is better than in those daysss.
Kind regards
Carl

Carl
3rd June 2003, 07:56 AM
Hi Bill,
Sorry i did not pop into to see you after the Wellington country park show.
In reply to your post on the Mazda 787b engine only the side plates were coated in ceramic and not the rotor housings.
The apex seals were ceramic.Rotor housings were chromed as in production engines.
Kind regards
Carl

Iwan
3rd June 2003, 08:44 AM
Carl, thank you for the information.

Well my opinion is not to go for this seals. Chattermarks may be one of the results.

Black is Chromoxyd or something with about 90% of CR2O2 together with some another stuf to support the CVD or PVD process. This material dont support nitro usage.
Gray should be Si3N4 wich is mutch better!

By coating you Rotorhausing (not only the sideplates) you will reduce the motor temperatur. Why? Couse you will reduce friction. By using ceramic on ceramic you will have nearly no friction. So it is important to coate your rotorhousing.

The discussion about Hurly is funny. If you dont put the lambda over 1.0 Hurly seals will work fine. But going over 1.0 you will blow you seals. As I know, Hurly seals were developed by Daimler (Mercedes Benz) in early '70s...

Regards,

Iwan

bill shurvinton
3rd June 2003, 01:27 PM
Now that is interesting. I keep meaning to pop over to a nitriding specialists a few miles away with a pile of bits for them to look at.

Of course if you coat everything with ceramic, where does the heat go? Only the rotor ( and therefore the oil) left

I will call them and report back on what they say (www.eltro.co.uk)

Bill

P.S. Don't worry Carl, I'll just pop over sometime as I am 'at leisure' for a while

Iwan
4th June 2003, 05:27 AM
Hi Bill, be carefull! Ask only for SI3N4. What many companys do, them coate with Aluminiumoxyd, Al2O3 which is also called "ceramic". Not every company support Si3N4.

Ask for CVD coating. Plasma coating is a new process.... I'm waiting for the price for coating my engine, then I will test the new plasma process. CVD is the best process for coating at the moment. 1000°C is to low.... them need a stronger laser.

Best Regards

Iwan