Information on Ceramic Apex Seals

[Glenn Butcher]

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” â€"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” â€"0.000”

(12A) 2.7525” +0.000” â€"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” â€"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]

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]

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]

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]

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]

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]

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]

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 Å' 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]

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]

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]

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]

Hi Guys
Sorry Sven didn\'t join the forum.
Martin Sintler

[Rx7-AIII]

These are the seals that Glenn put the info up about at the start of the thread.

[Glenn Butcher]

Hi Martin,

I thought you were Sven!  

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

[Herblenny]

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..