Ceramic Coatings - Dumps and Front Pipes.

[GTR_JOEY]

Intercooler return pipe??

As in the piping after the cooler?

[The Bogan]

I take this pearl away from your post rather than succumbing to a fit of facepalm.

Is that easier than explaining why removing heat from the engine bay or intake using wraps and other forms of insulation is bad.

I'm serious here, we all know what radiant heat can do in a engine bay and the loss of power with hot intake charge.

[GTSBoy]

It's because you have not paid any attention to the fact that I HAVE NEVER DISAGREED WITH THE STATEMENT THAT INSULATING HOT OR COLD PIPES IN AN ENGINE BAY IS A BAD THING FROM THE POINT OF VIEW OF HEAT TRANSFER. All I said is that in an industrial milleau, no-one would wrap a steel pipe or a stainless steel pipe with external insulation/lagging/cheesecloth/hessiansacks if the gases inside really bloody hot. BECAUSE IT'S NOT A GOOD IDEA to stress the metal that way. It's not good practice.

And no, I don't consider diesel engine exhaust manifolds and turbos to be "industrial". That's still effectively automotive, even if the bloody engine is hooked up to a pump or a generator or a propeller. And as has been said above by others, ship engine rooms need all the help they can get in staying cool.

[Missileman]

I ended up doing it myself because I'm a cheap bastard, though to be honest it was done primarily to tidy up my rusty heat shields and dump pipe, more than to achieve any reduction in engine bay temperatures.

2 cans of VHT Flame Proof Silica Ceramic Coat + 1 can of the same in Primer....

Edited January 7, 2015 by Missileman

[GTSBoy]

Keep in mind though that that VHT stuff should be almost like nothing at all compared to a proper arc/plasma deposited ceramic coating. The ceramic materials used in proper coatings are full of expensive rare earths and other classy residents of the top end of the periodic table, and top coats of like yttria stabilised zirconia and so on.

Edited January 7, 2015 by GTSBoy

[Missileman]

But does the price difference actually match the temperature difference? I considered a professional job, but decided my money was better spent elsewhere.

[DCIEVE]

It's because you have not paid any attention to the fact that I HAVE NEVER DISAGREED WITH THE STATEMENT THAT INSULATING HOT OR COLD PIPES IN AN ENGINE BAY IS A BAD THING FROM THE POINT OF VIEW OF HEAT TRANSFER. All I said is that in an industrial milleau, no-one would wrap a steel pipe or a stainless steel pipe with external insulation/lagging/cheesecloth/hessiansacks if the gases inside really bloody hot. BECAUSE IT'S NOT A GOOD IDEA to stress the metal that way. It's not good practice.

And no, I don't consider diesel engine exhaust manifolds and turbos to be "industrial". That's still effectively automotive, even if the bloody engine is hooked up to a pump or a generator or a propeller. And as has been said above by others, ship engine rooms need all the help they can get in staying cool.

The reasons for not lagging industrial equipment are for the most part completely irrelevant to this topic and an order of magnitude more complex than "it's not a good idea to stress metal that way". What is your point?

[GTSBoy]

The reasons for not lagging industrial equipment are for the most part completely irrelevant to this topic and an order of magnitude more complex than "it's not a good idea to stress metal that way". What is your point?

Well that statement is just bloody wrong. The relevance to the question at hand is 100%. The questions are 1) Does it (wrapping) stop the heat getting out of the pipe and into the engine bay, and 2) Does it damage the pipework. And the answer to both is yes. Absolutely yes. And all I said (effectively, spread out over a few posts now) is that car applications are so unimportant that the damage caused by wrapping is something that you just have to suck up, and that the damage caused by externally insulating SERIOUSLY hot pipework is the reason why it is not done in industrial applications. I didn't even start the mention of industrial applications. I was refuting someone else's fairly ill advised introduction of "they do it in industrial applications" into this thread.

[GTSBoy]

But does the price difference actually match the temperature difference? I considered a professional job, but decided my money was better spent elsewhere.

Fair enough. I would expect it will have some benefit, not the least from reducing the emissivity of the surface (by being more pale grey than dark grey).

[The Bogan]

LOL, from your post number 85 you have been talking about "your" industrial application and the "cars are toys" compared to what ever furnace you have worked on.

I really couldn't give a rats arse about your "industrial furnaces" or the like, what I have been talking about is reducing under bonnet temps through exhaust wrapping.

And what about the external coatings which this tread is about, don't they help retain the heat inside the pipe to allow the gasses to flow more efficiently, whereas you seem to disagree and say its not a good idea to stress the metal that way, its not good practice?

Maybe for a your industrial furnace, but we are not talking about your industrial furnace.

Me, I wrap my exhausts and manifolds to the CAT, I have also use that gold sheet on air boxes and intake pipes as well as placing it under the bonnet to protect the fibreglass, I've also added some heat shielding between the CAT and the body because it was getting so hot and radiating heat through the passenger floor.

Rock and roll

Also head out to ICI (ORICA) to see some of my ill advised insulation work of industrial plant pipe work, Olifins would be a good place to start.

[Missileman]

Apart from stopping you fiberglass bonnet delaminating, does all the wraps and ceramic coat help make any extra kilowatts and is the extra weight added offset by said extra power?

[The Bogan]

You may make a couple of kw, my main concern is keeping under bonnet temps down thus avoiding damage to wires and vac lines and stuff.

The way I see it is if I have upgraded or changed a part i.e. exhaust manifold, I will need to replace the heat shielding that came with it when it was stock, other wise I have only done half a job.

Have a squiz at some of the shielding and insulation that's going on in the high end market to keep the under boonet temps at bay, some of them are works of art.

As for weight of ceramics I couldn't say, but I would assume it to be minimal, like a couple of hundred grams at a guess, some one else might know.

As for the wrap, my last job was on a set of headers 4-2-1 all the way to the cat, used 1 1/2 50ft rolls, weight? maybe 1.5kg.

Gold stuff was less than the weight of A3 paper.

Is it worth it, I haven't melted wires of vac lines and my under bonnet temps are vastly improved.

[GTSBoy]

LOL, from your post number 85 you have been talking about "your" industrial application and the "cars are toys" compared to what ever furnace you have worked on.

I really couldn't give a rats arse about your "industrial furnaces" or the like, what I have been talking about is reducing under bonnet temps through exhaust wrapping.

And what about the external coatings which this tread is about, don't they help retain the heat inside the pipe to allow the gasses to flow more efficiently, whereas you seem to disagree and say its not a good idea to stress the metal that way, its not good practice?

Maybe for a your industrial furnace, but we are not talking about your industrial furnace.

Me, I wrap my exhausts and manifolds to the CAT, I have also use that gold sheet on air boxes and intake pipes as well as placing it under the bonnet to protect the fibreglass, I've also added some heat shielding between the CAT and the body because it was getting so hot and radiating heat through the passenger floor.

Rock and roll

Also head out to ICI (ORICA) to see some of my ill advised insulation work of industrial plant pipe work, Olifins would be a good place to start.

You are so on crack that it's not funny. What are the process temperatures inside those ducts that you have installed insulation on? Are the gases inside oxidising, or reducing? Are the ducts mild or stainless? What corrosion mechanisms are possible? You don't know do you? That's because someone else designed the insulation system that you installed and that's because they knew the answers to those questions. And I will tell you one thing that I do know for absolute sure, is that the temperatures inside those ducts that you have (now famously) installed insulation on, are nowhere near as high as a petrol engine turbo exhaust flow path. Would have to be <<500°C on mild steel, probably <300°C. If stainless, then almost certainly <<700°C. My stock Neo exhaust manifold temperature runs at ~800-900°C when leaning on it. That's pretty bloody harsh conditions. If it were a cheapy stainless eBay manifold and I wrapped it, or possibly even if it was externally coated, then I would expect it to shit itself enormously if I ran it hard like that a lot of the time. (Granted, it doesn't get run hard like that much of the time, so it would possibly be fine - especially if it was coated rather than wrapped).

If you want my specific comment on the value of coating exhaust components in car applications, I would say (and effectively already have, if you had read properly) that putting it on the inside has got to be far superior to putting it on the outside, because that way you stop some of the heat getting to the metal, instead of trapping it inside like wrapping does. And as there have been many many people experience failures of exhaust plumbing of all descriptions when wrapped, I would say that is a perfectly valid point of view. I would also say that the difficulty of properly cleaning the inside of used exhaust plumbing makes it challenging to get a decent application of ceramic coating, therefore making it something that you would be better off doing to brand new stuff than used stuff.

I never argued that the stuff (coating or wrapping) doesn't work. Just that there were real reasons why it's not always a great idea, and that the "industry does it so it must be great" argument was in fact false. I don't know when you started putting reflective insulation on your cars, but I stuck it on the airbox, inlet plumbing and so on of my car LAST CENTURY. That's my current car. It's still there. I won't talk about the cars I was driving in the 80s and 90s, because they didn't have so much of a problem with generating and retaining heat. Alright, the ALFA did, but that was mainly the starter motor getting too hot to work on a summer afternoon.

[GTSBoy]

Apart from stopping you fiberglass bonnet delaminating, does all the wraps and ceramic coat help make any extra kilowatts and is the extra weight added offset by said extra power?

Keeping exhaust gases hot before the turbo has a definite performance advantage in terms of retaining the energy in the gases. Should benefit spool if not outright power. In real terms, getting the turbo on earlier is probably worth more than a couple of extra kW up top in almost every application anyway, except salt flat racing and so on. In all other respects, the benefits are as mlr says. Keeping the heat away from things you don't want to be hot.

[Missileman]

Yup totally agreed that that the energy not transmitted through the pipe work (pre turbo) has to to be used spinning the turbine, and increasing efficiency.

Edited January 7, 2015 by Missileman

[DCIEVE]

Well that statement is just bloody wrong. The relevance to the question at hand is 100%. The questions are 1) Does it (wrapping) stop the heat getting out of the pipe and into the engine bay, and 2) Does it damage the pipework. And the answer to both is yes. Absolutely yes. And all I said (effectively, spread out over a few posts now) is that car applications are so unimportant that the damage caused by wrapping is something that you just have to suck up, and that the damage caused by externally insulating SERIOUSLY hot pipework is the reason why it is not done in industrial applications. I didn't even start the mention of industrial applications. I was refuting someone else's fairly ill advised introduction of "they do it in industrial applications" into this thread.

Actually agree with most of that. Play on.

[The Bogan]

Again GTSboy, I never said I designed them, do you feel smart point out something I pointed out.

What were the pipes made from, who knows, I dont, but they were lagged with fibreglass mostly, I didn't need to know ant technical stuff.

I believe I explained what I have learnt and what I have done, I may not be a engineer designing the products but I believe I know the basics of what and why.

I have also picked a lot of stuff from guys at the track on what works and what is a waste.

Next time your furnace is out for a track day or running the 1/4 give me a bell, it would be good to see how it performs.

I believe you are an extremely knowledgeable gentleman who also has had vast experience in having your head well up your own arse.

Enjoy the view

[Griffin]

I started out playing wit mitsubishi and Toyota which have the exhaust on the drivers side close to the brake booster, clutch master, steering rack / box etc. Coatings made a big improvement in temp control. ....... wish I never bought a nissan.

[Roy]

I am not going to go into all here as i reckon based on the bickering I will post this up and after you all argue and swing dicks you will get to the truth

What happens to 300 series stainless steel when it is welded and why purging and shielding with argon is critical. Also what carbide precipitation is and consider why ceramic coating is great for that. When you ladies get to the bottom of that we can move on to wrapping

[GTSBoy]

Or we could talk about stress corrosion cracking, pinhole corrosion, sulphidation, carburisation, hot corrosion, fluoride and chloride attack, and all the other attack vectors that I have to worry about when designing pressure vessels out of 304L, burner components out of 253MA and inconel (and other 600 series alloys), why we tried to use Haynes HR-120 despite the fact that it is miserable to weld and likes to crack from the root on short and shallow welds, etc.

Carbide precipitation, pinhole corrosion and stress corrosion cracking actually share some similarities in what happens. Any time you get ceramic forming from the alloying elements from the 300 series steels migrating out of the grains and into the grain boundary regions is not a good time. I had to investigate a terrible pressure vessel explosion where a nearly brand new vessel went pop. Turned out, putting it next to the seaside (industrial area near the Brisbane ports), operating it at the temperature that they did and with cyclical pressure loading inside was just the right recipe for chloride mediated pinhole corrosion. Left the grains almost completely depleted of chrome and a huge amount of chromium chloride ceramic material in between. The then pretty mild steel that was left in the grains didn't last more than a few hours. Quite exciting.

I guess your point about using argon is more about not using CO2. The presence of carbon is the obvious problem there.

Do I pass teacher?