X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail08.syd.optusnet.com.au ([211.29.132.189] verified) by logan.com (CommuniGate Pro SMTP 5.2c1) with ESMTPS id 2464028 for flyrotary@lancaironline.net; Fri, 09 Nov 2007 17:10:41 -0500 Received-SPF: none receiver=logan.com; client-ip=211.29.132.189; envelope-from=lendich@optusnet.com.au Received: from george (d211-31-228-51.dsl.nsw.optusnet.com.au [211.31.228.51]) by mail08.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id lA9M9v7d011242 for ; Sat, 10 Nov 2007 09:09:58 +1100 Message-ID: <008201c8231d$485fa2b0$33e41fd3@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Spin Tech Date: Sat, 10 Nov 2007 08:10:04 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_007F_01C82371.1951B180" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Antivirus: avast! (VPS 0657-0, 12/12/2006), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_007F_01C82371.1951B180 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Monty, The most common SS available are 302, 304 and 316. I guess the 316 ( = marine grade SS) will fall into the higher chromium and nickel content = so should be pretty good also. The 302 I'm unsure of, I think this work hardens and would therefore be = more brittle - but if you have that info, please advise. George ( down under)=20 ----- Original Message -----=20 From: M Roberts=20 To: Rotary motors in aircraft=20 Sent: Saturday, November 10, 2007 2:44 AM Subject: [FlyRotary] Re: Spin Tech Ed, Is there any consensus at this time as to which alloy (304 or 409) = is the most=20 durable for our hot breathed 13B rotarys ?? -- Kelly Troyer=20 "Dyke Delta"_13B ROTARY Engine=20 "RWS"_RD1C/EC2/EM2=20 "Mistral"_Backplate/Oil Manifold=20 Kelly, I'm not Ed but I did sleep at a Holiday Inn Express!! Alloys to use for Rotary engine exhaust in order of decreasing = desirability (and cost) 1.) Inconel 2.) 321 Stainless 3.) 304 Stainless 4.) 409 Stainless 5.) Mild steel Basically 409 is a low chromium stainless designed for the automotive = market, specifically for exhaust tubing. It does not polish well and = will develop a protective coating of rust. It will live just fine, but = will be less attractive. If you move up in cost you get a higher chromium and nickel content = and therefore a higher temp resistance and creep resistance. This means = you can make everything lighter and thinner. Of course it becomes much = more important to properly design the manifold for expansion/thermal = cycling loads the thinner it gets. So you will have to put a lot of = slip joints and metal bellows in it to seal it up if it is a turbo = installation. So.....how much do you want to spend to save 5 lbs or have = a polished tail pipe is the question. Mild steel will work fine if it is thick enough. Especially if you = coat it with ceramic. I suppose you could also coat the 409 stainless = with ceramic if you want a nice finish, but it might be less expensive = to just use 304 at that point. Monty=20 -------------------------------------------------------------------------= ----- No virus found in this incoming message. Checked by AVG Free Edition.=20 Version: 7.5.503 / Virus Database: 269.15.24/1115 - Release Date: = 7/11/2007 9:21 AM ------=_NextPart_000_007F_01C82371.1951B180 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Monty,
The most common SS available are 302, = 304 and 316.=20 I guess the 316 ( marine grade SS) will fall into the higher chromium = and nickel=20 content so should be pretty good also.
The 302 I'm unsure of, I think this = work hardens=20 and would therefore be more brittle - but if you have that info, please=20 advise.
George ( down under) 
----- Original Message -----
From:=20 M=20 Roberts
Sent: Saturday, November 10, = 2007 2:44=20 AM
Subject: [FlyRotary] Re: Spin = Tech

Ed,
  Is there any consensus at this = time as to=20 which alloy (304 or 409) is the most
durable for our hot breathed 13B = rotarys=20 ??
--
Kelly Troyer=20
"Dyke Delta"_13B ROTARY Engine
"RWS"_RD1C/EC2/EM2=20
"Mistral"_Backplate/Oil Manifold
 
Kelly,
 
I'm = not Ed but I=20 did sleep at a Holiday Inn Express!!
 
Alloys to use for=20 Rotary engine exhaust in order of decreasing desirability (and=20 cost)
 
1.) = Inconel
 
2.) = 321=20 Stainless
 
3.) = 304=20 Stainless
 
4.) = 409=20 Stainless
 
5.) = Mild=20 steel
 
 
Basically 409 is a=20 low chromium stainless designed for the automotive market, = specifically for=20 exhaust tubing. It does not polish well and will develop a protective = coating=20 of rust. It will live just fine, but will be less = attractive.
 
If = you move up in=20 cost you get a higher chromium and nickel content and therefore a = higher temp=20 resistance and creep resistance. This means you can make everything = lighter=20 and thinner. Of course it becomes much more important to properly = design the=20 manifold for expansion/thermal cycling loads the thinner it gets. = So  you=20 will have to put a lot of slip joints and metal bellows in it to seal = it up if=20 it is a turbo installation. So.....how much do you want to spend to = save 5 lbs=20 or have a polished tail pipe is the question.
 
Mild steel will=20 work fine if it is thick enough. Especially if you coat it with = ceramic. I=20 suppose you could also coat the 409 stainless with ceramic if you want = a nice=20 finish, but it might be less expensive to just use 304 at that=20 point.
 
Monty=20

No virus found in this incoming message.
Checked by AVG Free = Edition.
Version: 7.5.503 / Virus Database: 269.15.24/1115 - = Release Date:=20 7/11/2007 9:21 AM
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