X-Virus-Scanned: clean according to Sophos on Logan.com From: "William Jepson" Received: from mail-ua0-f174.google.com ([209.85.217.174] verified) by logan.com (CommuniGate Pro SMTP 6.1.14) with ESMTPS id 9396018 for flyrotary@lancaironline.net; Mon, 23 Jan 2017 15:46:08 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.217.174; envelope-from=wrjjrs@gmail.com Received: by mail-ua0-f174.google.com with SMTP id y9so119814125uae.2 for ; Mon, 23 Jan 2017 12:46:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to; bh=s245Z8UDLgpKLpn6HdLESSBoEaVch1u4u8u1yFqxGmY=; b=MZeMhkancsiEUYYslhsoLeTm9mF5JrQQvsLJ/0pFeZYflp40LRCtkHzIYIE1AfbHZA yb/Qg/nVjHQF7KAH6Fr64qQFjnJWc0L/jLllyBkVhZOyw1dWZnjRzCfnE1mTjJJbNvH7 9mO2obKH8pm4Oq0901Ik1ex0x4d1Z4X3xa2Si6bX76+wYpZ2nB8FP9eKBIoevm02riG5 Etb9Q7n6p8zKpcByO3Z55OoLei8DP2MtZYjU7sZiwenNJKSyzmEbrtZXnVTgAqTBjhXO cB2yaP7tUrI6I7CQKleN//5GtMXgUHHgbCmnjbt27Dy3K3WV2uQo05j7U42nyt10cXSM pXyg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to; bh=s245Z8UDLgpKLpn6HdLESSBoEaVch1u4u8u1yFqxGmY=; b=nTRh4y0rfjjW9a6DKYmdh+VUiwrNyzzT1B6DY1WthpHoQxC6RqrI+oNzZxYv/EIm6+ CJWQmtPm4eLlgk74xTq8lf8r9d0WpmBo/yCBtULLvxZwzmMRxnN34xCPcoZV4HjtbCtW NJsaSzuq9r1TRUU9Z7sVDMugTDHBtsRIcv1pXhRQcM9+jzTqmyN7Y9k85BaYx8R2Xyur /boajycww64jaXx3wo2FsXoukV2Q72SRQ/2XWsyXrfYxoOUIL7S6zeWXrXQuHeYXhJiz SVb6g7AmgtMXWbMgKpuPn9V6EQrGuh3PMAvlGaFeBJ6jJa0bIMQkK0lEQmvPI8a49Sbx HNNg== X-Gm-Message-State: AIkVDXID6RcrvpfsEh6KADp0NhuroqOO99qgiVZTZKmLUovCBxO7Lmc9jQjGrnf9kV9jalQEYzWs/cQA5rh5dg== X-Received: by 10.159.37.207 with SMTP id 73mr16373345uaf.67.1485204349675; Mon, 23 Jan 2017 12:45:49 -0800 (PST) MIME-Version: 1.0 Received: by 10.31.56.18 with HTTP; Mon, 23 Jan 2017 12:45:49 -0800 (PST) In-Reply-To: References: Date: Mon, 23 Jan 2017 12:45:49 -0800 Message-ID: Subject: Re: [FlyRotary] Re: exhaust wraps and blankets To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=001a113d0632ae71320546c915c3 --001a113d0632ae71320546c915c3 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Rich, anything that keeps the heat in will make the exhaust exiting hotter. (Obviously) On a metal prop I doubt it would be a problem unless you run the exhaust very close to the prop. Various composite props you better ask the manufacturer, it is a concern. You can also run the exit into a short annulus and draw air in around the exhaust to help cool it quickly. Like a really short augmenter. You would need to test the heat, but I haven't heard of anyone having a big problem with this and wraps and ceramic coatings have been around for 20 years. Bill On Mon, Jan 23, 2017 at 12:10 PM, ARGOLDMAN wrote: > I am interested in ceramic coatings also. A question arises in the areas > of slip joints or ball joints. > > Also with pushers (perish the thought) what will the effect of a hotter > exhaust blowing on the propeller in a more concentrated fashion vs a cool= er > blast modified by the radiation of the exhaust system being cooled by > moving air leaving the cowling? > Rich > > In a message dated 1/20/2017 1:14:08 P.M. Central Standard Time, > flyrotary@lancaironline.net writes: > > Lynn, Et All, > I want to mention the alternative to heat wraps, ceramic coatings. I have > used Jet-Hot on headers for insulation and performance. Early Jet-Hot > didn't have a super high temp coating that would stand up to rotary exhau= st > temperatures. They have had an 1800=C2=B0F+ material for some time now. T= hey > needed to have a coating that would stand up to turbo header temperatures= . > They have a service where they apply to the inside and outside of the > pipes. There is a very minor smoothing effect that even help HP. The > insinuative effect is as good or better than most heat wraps, and the pip= es > look great too. I have used them for pipes on racing motorcycles that hav= e > tight fairings. I measured a 30=C2=B0 difference inside my fairing with n= o other > changes using color change tape, but I think is was even better than that > in terms of radiated heat. I had a battery located in the fairing mounted > low in front of the headers. This no longer was showing bubbling and > melting effects, and survived a 4 hour endurance race as a total loss > system. I don't work for those guys, and wasn't sponsored by them either.= I > highly recommend them. > Bill Jepson > > On Fri, Jan 20, 2017 at 10:07 AM, Lehanover > wrote: > >> The good news is: Heat wrap tape works great. Amazing drop in temps >> around the engine. >> >> The bad news is: Carbon steel headers, even in .140" wall turn to dust i= n >> one racing season. >> Literally you can crush the header pipes with one hand. The outside >> radius of bent tubes is thinner and will fail sooner.That bright orange >> header you see in tapes of dyno runs is exactly what your heat taped hea= der >> looks like. How strong is bright orange steel? Even stainless? Steel >> under stress fails sooner. Each down pipe should be free to twist and >> squirm a bit as it heats and cools. Only stainless down tubes and only >> thick wall stainless at that. If you wrap the whole thing the exiting >> exhaust gasses will be close the EGT readings on the gage. Will your car >> muffler hold up to 1600 degrees. If some heat tape falls off along those >> pipes will the bright orange pipe damage anything important? >> >> Then a collector to take the two or three tubes (all exactly the same >> length) in and then the beginning of the exhaust system. Collector attac= hes >> with stiff springs the down pipes. A strap fail safe in case a spring >> fails. Two strands of safety wire through the spring loosely in case the >> spring fails (they like to sing along with the engine) you know and a pi= ece >> of spring will find a place to get stuck that will be the least helpful. >> The collector is supported loosely by a bracket that moves with the >> engine. >> >> Then a slip joint or flex joint of some kind to account for the engine >> moving about with power changes. Then the exhaust system, mufflers and >> so-on may be mounted to the chassis. >> Non rigid mountings to keep the noise down would be good. >> >> The whole system may may be covered with .015" stainless shielding >> spaced one inch at least off of the tubes. Air blowing between the >> shielding and the header/exhaust tubing does a good job of reducing >> temperatures under hood/cowl, and keeps the shielding from radiating hig= her >> temps. >> >> Been there. Done that. >> >> Lynn E. Hanover >> >> In a message dated 1/20/2017 9:11:57 A.M. Eastern Standard Time, >> flyrotary@lancaironline.net writes: >> >> My problem with the wrap is that it makes inspection somewhere between >> difficult and impossible. I opted for wrapping the muffler in a .025 >> stainless shroud that went all the way to the air exit, and ducting >> airflow through it. Sort of a muffler over the muffler. It'd be heavy, >> but the shroud could have been lined on the inside with blanket material >> for more heat isolation. >> >> >> >> >> On Friday, January 20, 2017 1:48 AM, Todd Bartrim < >> flyrotary@lancaironline.net> wrote: >> >> >> So I'm interested to hear about thoughts on exhaust wraps? I know that >> some people like them and others don't. Also some header manufactures do= n't >> like them. But the fact is that we have one heck of a lot of radiant hea= t >> under the cowl. Heat shields help some but I really just want to try to >> keep most of the heat going down the exhaust pipe. I know ceramic coatin= g >> on the inside of the pipe is the best solution, but once a pipe is no >> longer new it becomes more difficult to apply and hope for it to stay. O= n >> my first ever engine build I had my rotors ceramic coated as that was >> supposed to reduce oil heating, but after I had a little detonation >> incident I found during the rebuild that much of the ceramic had come of= f >> due to the shock of detonation. In my mind, I don't feel that ceramic >> coating the outside of the pipe is any better than wrapping them as the >> heat is still absorbed by the metal but unable to radiate out. >> But the biggest argument against ceramic coating is that once it's >> done, you can't modify your pipe (welding etc.) without having it redone >> again. A good example of this just happened as I'd already had my exhaus= t >> completed some months ago, not expecting that it would change again... B= ut >> then somebody on this list started saying how great his PLX wideband sen= sor >> was, blah, blah, blah, and suddenly I'm out a couple of hundred bucks an= d >> having to redo my exhaust because it's recommended that the sensor be >> located at an 15 degree angle, no less than 36" downstream from a turbo, >> while my old narrow band sensor was only 14" downstream. So rather than >> leaving the old sensor in place I decided to cut it off along with anoth= er >> (long ago) incorrectly placed EGT port and weld a patch over it, then >> install a new O2 bung downstream. Pretty simple to unwrap, weld and re-w= rap. >> So as far as wraps go... lets hear it. Good, bad or ugly. >> >> Next is blankets. I have the original mazda metal turbo shroud in place >> but then I bought a large turbo blanket to fit over that. The exhaust >> manifold that the turbo bolts to also has a stck Mazda metal sheild but = I >> made one to fit over that as I feel these 2 items probably account for t= he >> largest source of under-cowl heat and since the oli cooler is directly >> below that, I want to eliminate that source of radiant heat transfer. I >> made this cover using 2 different styles of welding blanket sewed togeth= er >> like a quilt. The ball joint in my exhaust pipe, I decided to also cover >> with a blanket like this rather than wrapping it, so I made it into a >> sleeve that slides over the joint. Finally we get down to the muffler wh= ich >> is located inside a housing (more on that in a another post), due to it'= s >> location inside a housing I decided to put a quilted blanket sleeve over >> that one too. >> >> Pics of all this and more at this link. >> >> https://goo.gl/photos/NvD5YH4jwbktESi88 >> >> Todd Bartrim >> >> C-FSTB >> RV9 13Bturbo >> >> >> > --001a113d0632ae71320546c915c3 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Rich,
anything that keeps the heat in will make the ex= haust exiting hotter. (Obviously) On a metal prop I doubt it would be a pro= blem unless you run the exhaust very close to the prop. Various composite p= rops you better ask the manufacturer, it is a concern. You can also run the= exit into a short annulus and draw air in around the exhaust to help cool = it quickly. Like a really short augmenter. You would need to test the heat,= but I haven't heard of anyone having a big problem with this and wraps= and ceramic coatings have been around for 20 years.
Bill

On Mon, Jan 2= 3, 2017 at 12:10 PM, ARGOLDMAN <flyrotary@lancaironline.net&= gt; wrote:
I am interested in ceramic coatings also. A question arises in the are= as of=20 slip joints or ball joints.
=C2=A0
Also with pushers (perish the thought) what will the effect of a hotte= r=20 exhaust blowing on the propeller in a more concentrated fashion vs a cooler= =20 blast modified by the radiation of the exhaust system being cooled by movin= g air=20 leaving the cowling?
Rich
=C2=A0
In a message dated 1/20/2017 1:14:08 P.M. Central Standard Time,=20 flyrotary@= lancaironline.net writes:
Lynn, Et= All,=20
I want to mention the alternative to heat wraps, ceramic coatings. I= have=20 used Jet-Hot on headers for insulation and performance. Early Jet-Hot did= n't=20 have a super high temp coating that would stand up to rotary exhaust=20 temperatures. They have had an 1800=C2=B0F+ material for some time now. T= hey needed=20 to have a coating that would stand up to turbo header temperatures. They = have=20 a service where they apply to the inside and outside of the pipes. There = is a=20 very minor smoothing effect that even help HP. The insinuative effect is = as=20 good or better than most heat wraps, and the pipes look great too. I have= used=20 them for pipes on racing motorcycles that have tight fairings. I measured= a=20 30=C2=B0 difference inside my fairing with no other changes using color c= hange=20 tape, but I think is was even better than that in terms of radiated heat.= I=20 had a battery located in the fairing mounted low in front of the headers.= This=20 no longer was showing bubbling and melting effects, and survived a 4 hour= =20 endurance race as a total loss system. I don't work for those guys, a= nd wasn't=20 sponsored by them either. I highly recommend them.
Bill Jepson=C2=A0

On Fri, Jan 20, 2017 at 10:07 AM, Lehanover <flyrotary@lancaironl= ine.net> wrote:
The good news is: Heat wrap tape works great. Amazing drop in temp= s=20 around the engine.
=C2=A0
The bad news is: Carbon steel headers, even in .140" wall=C2= =A0turn to=20 dust in one racing season.
Literally you can crush the header pipes with one hand. The outsid= e=20 radius of bent tubes is thinner and will =C2=A0fail sooner.That bright= =20 orange header you see in tapes of dyno runs is exactly what your heat t= aped=20 header looks like. How strong is bright orange steel? Even stainless?= =C2=A0=20 =C2=A0Steel under stress fails sooner.=C2=A0 Each down pipe should be f= ree=20 to twist and squirm a bit as it heats and cools. Only stainless down tu= bes=20 and only thick wall stainless at that. If you wrap the whole thing the= =20 exiting exhaust gasses will be close the=C2=A0EGT readings on the gage.= Will=20 your car muffler hold up to 1600 degrees. If some heat tape falls off a= long=20 those pipes will the bright orange pipe damage anything important?
=C2=A0
Then a collector to take the two or three tubes (all exactly the s= ame=20 length) in and then the beginning of the exhaust system. Collector atta= ches=20 with stiff springs the=C2=A0down pipes. A strap=C2=A0fail safe in case = a=20 spring fails. Two strands of safety wire through the spring loosely in = case=20 the spring fails (they like to sing along with the engine) you know and= a=20 piece of spring will find a place to get stuck that will be the least= =20 helpful. The collector is supported=C2=A0 loosely=C2=A0by a bracket tha= t=20 moves with the engine.
=C2=A0
Then a slip joint or flex joint of some kind to account for the en= gine=20 moving about with power changes. Then the exhaust system, mufflers and = so-on=20 may be mounted to the chassis.
Non rigid mountings to keep the noise down would be good.
=C2=A0
The whole system may =C2=A0may be covered with .015" stainles= s=20 shielding spaced one inch at least off of the tubes.=C2=A0 Air blowing= =20 between the shielding and the header/exhaust tubing does a good job of= =20 reducing temperatures under hood/cowl, and keeps the shielding from=20 radiating higher temps.
=C2=A0
Been there. Done that.
=C2=A0
Lynn E. Hanover
=C2=A0
In a message dated 1/20/2017 9:11:57 A.M. Eastern Standard Time, <= a title=3D"mailto:flyrotary@lancaironline.net" href=3D"mailto:flyrotary@lan= caironline.net" target=3D"_blank">flyrotary@lancaironline.net writes:
My problem=20 with the wrap is that it makes inspection somewhere between difficult= and=20 impossible.=C2=A0 I opted for wrapping the muffler in a .025 stainles= s=20 shroud that went all the way to the air exit, =C2=A0and ducting airfl= ow=20 through it.=C2=A0 Sort of a muffler over the muffler.=C2=A0 It'd = be heavy,=20 but the shroud could have been lined on the inside with blanket mater= ial=20 for more heat isolation.




On Friday, January 2= 0, 2017 1:48 AM,=20 Todd Bartrim <flyrotary@lancair= online.net>=20 wrote:


So I'm interested to hear about thoughts on exhaust wraps? I= know=20 that some people like them and others don't. Also some header man= ufactures=20 don't like them. But the fact is that we have one heck of a lot o= f radiant=20 heat under the cowl. Heat shields help some but I really just want to= try=20 to keep most of the heat going down the exhaust pipe. I know ceramic= =20 coating on the inside of the pipe is the best solution, but once a pi= pe is=20 no longer new it becomes more difficult to apply and hope for it to s= tay.=20 On my first ever engine build I had my rotors ceramic coated as that = was=20 supposed to reduce oil heating, but after I had a little detonation= =20 incident I found during the rebuild that much of the ceramic had come= off=20 due to the shock of detonation. In my mind, I don't feel that cer= amic=20 coating the outside of the pipe is any better than wrapping them as t= he=20 heat is still absorbed by the metal but unable to radiate out.
=C2=A0 =C2=A0But the biggest argument against ceramic coating is= that=20 once it's done, you can't modify your pipe (welding etc.) wit= hout having=20 it redone again. A good example of this just happened as I'd alre= ady had=20 my exhaust completed some months ago, not expecting that it would cha= nge=20 again... But then somebody on this list started saying how great his = PLX=20 wideband sensor was, blah, blah, blah, and suddenly I'm out a cou= ple of=20 hundred bucks and having to redo my exhaust because it's recommen= ded that=20 the sensor be located at an 15 degree angle, no less than 36" do= wnstream=20 from a turbo, while my old narrow band sensor was only 14" downs= tream. So=20 rather than leaving the old sensor in place I decided to cut it off a= long=20 with another (long ago) incorrectly placed EGT port and weld a patch = over=20 it, then install a new O2 bung downstream. Pretty simple to unwrap, w= eld=20 and re-wrap.
So as far as wraps go... lets hear it. Good, bad or ugly.
=C2=A0=C2=A0
=C2=A0Next is blankets. I have the original mazda metal turbo sh= roud=20 in place but then I bought a large turbo blanket to fit over that. Th= e=20 exhaust manifold that the turbo bolts to also has a stck Mazda metal= =20 sheild but I made one to fit over that as I feel these 2 items probab= ly=20 account for the largest source of under-cowl heat and since the oli c= ooler=20 is directly below that, I want to eliminate that source of radiant he= at=20 transfer. I made this cover using 2 different styles of welding blank= et=20 sewed together like a quilt. The ball joint in my exhaust pipe, I dec= ided=20 to also cover with a blanket like this rather than wrapping it, so I = made=20 it into a sleeve that slides over the joint. Finally we get down to t= he=20 muffler which is located inside a housing (more on that in a another= =20 post), due to it's location inside a housing I decided to put a q= uilted=20 blanket sleeve over that one too.

Pics of all this and more at this link.


Todd Bartrim

C-FSTB
RV9=20 13Bturbo



=

--001a113d0632ae71320546c915c3--