Late Marque Spitfire Exhausts…

Elliott,

Perhaps a letter to Rolls Royce Heritage Trust would elicit the particular Nickel Chrome Iron Alloy used on the Spitfire and other Merlin application exhausts.

The original specification will almost certainly have been superceded but there should be a current equivalent.

Mark

Re: Just off the top of my head

Originally posted by Mark12
😉

Inconel Alloy Technical Data

CHARACTERISTICS
Service 2,000°F (1,094°C)
Melting Point 2,500°F (1,372°C)

PROPERTIES
Nickel-Chromium-Iron alloy
Resists corrosion and heat
High strength and good workability
Virtually immune to chloride-ion stress-corrosion cracking
Not hardened by precipitation
Resistant to sulfur compounds
Resistant to oxidizing conditions at high temperatures

CHEMICAL COMPOSITION
Nickel (plus Cobalt) 72.0% min
Chromium 14 – 17%
Iron 6 – 10%
Carbon 0.15% max
Manganese 1.0% max
Sulfur 0.015% max
Silicone 0.50% max
Copper 0.50% max

PHYSICAL CONSTANTS
Density 0.304 lb/cu in (8.43 gm/cu cm)
Specific Heat 0.106 (at 70deg;F, Btu/lb/ °F)
Poisson’s Ratio 0.29 (at 70°F)
Electrical Resistivity 620 (at 70°F, ohm/circ mil/ft)
Curie Temperature 192°F
Permeability 1.010 (at 70°F and 200 oersted)
Thermal Conductivity 103 (Btu in/ft2 h °F))

APPLICATIONS
Heat treating industry for retorts, muffles, roller hearths, and other furnace components for heat-treating baskets and trays
Aeronauts industry
Electronics industry
Nuclear reactors

Mark

Very impressive as usual Mark, but are these compositions for the type of Inconel used in aircraft exhaust stubs – or just general specs? There are at least 20 different Inconel alloy available 🙁

Thanks anyway tho 🙂

Elliott

I resemble that remark. 🙂

Mark

Must be difficult to get a hat over that lot. 😀

Just off the top of my head

😉

Inconel Alloy Technical Data

CHARACTERISTICS
Service 2,000°F (1,094°C)
Melting Point 2,500°F (1,372°C)

PROPERTIES
Nickel-Chromium-Iron alloy
Resists corrosion and heat
High strength and good workability
Virtually immune to chloride-ion stress-corrosion cracking
Not hardened by precipitation
Resistant to sulfur compounds
Resistant to oxidizing conditions at high temperatures

CHEMICAL COMPOSITION
Nickel (plus Cobalt) 72.0% min
Chromium 14 – 17%
Iron 6 – 10%
Carbon 0.15% max
Manganese 1.0% max
Sulfur 0.015% max
Silicone 0.50% max
Copper 0.50% max

PHYSICAL CONSTANTS
Density 0.304 lb/cu in (8.43 gm/cu cm)
Specific Heat 0.106 (at 70deg;F, Btu/lb/ °F)
Poisson’s Ratio 0.29 (at 70°F)
Electrical Resistivity 620 (at 70°F, ohm/circ mil/ft)
Curie Temperature 192°F
Permeability 1.010 (at 70°F and 200 oersted)
Thermal Conductivity 103 (Btu in/ft2 h °F))

APPLICATIONS
Heat treating industry for retorts, muffles, roller hearths, and other furnace components for heat-treating baskets and trays
Aeronauts industry
Electronics industry
Nuclear reactors

Mark

Originally posted by Bruce
Many of the WW2 stacks, particularly the complex double entry ones were made of Inconel – I dont know the make up of this alloy, but suffice to say it is less prone to cracking than stainless, and doesnt rust like mild steel.

Just to confuse the issue…..

Bruce

Does anyone out there know which Inconel alloy was used in these stubs?

Thanks a million

Elliott

Originally posted by Bruce
Many of the WW2 stacks, particularly the complex double entry ones were made of Inconel – I dont know the make up of this alloy, but suffice to say it is less prone to cracking than stainless, and doesnt rust like mild steel.

Just to confuse the issue…..

Like Mark said, there’s stainless and stainless.

Inconel is a trade name covering a range of nickel alloys.

In similar vein, Dural is a trade name covering a range of aluminium alloys. The word Dural on it’s own means nothing except it’s an alloy, not pure aluminium. (That bit I DO know about, I spent years flogging the stuff!)

Originally posted by Mark12
I suspect they don’t have the budget of about £80k to obtain one either.

Mark

There’s a lesson to be learned there, children – don’t prang your prop!!

mike currill

I spoke to ‘the Major ‘ last year and asked if there was any possibility of seeing AB910 back with a three blade propeller at some time in the future. He told me that they just don’t have one. I suspect they don’t have the budget of about £80k to obtain one either.

Mark

Originally posted by Mark V
Chris,

The BBMF has a policy of engine and prop interchangibility to ensure continuity of operations by reducing the number of spare props & engines they need to carry. This is why you will sometimes see unusual combinations.

I cannot remember AR501 ever having three stack exhausts.

Hence the reason that the BBMF hurricanes have at times been seen with 4 blade props

That’s what I get when trying to be funny. I was being facetious about the SS Exhausts…

So why don’t the Mustang boys polish them then? Some of them would polish ANYTHING, so why not the exhausts!?! :p

Many of the WW2 stacks, particularly the complex double entry ones were made of Inconel – I dont know the make up of this alloy, but suffice to say it is less prone to cracking than stainless, and doesnt rust like mild steel.

Just to confuse the issue…..

Bruce

Originally posted by warbirdUK
Just a quickie, Stainless exhaust stubs don’t last as long as the steel ones.
Cheers……………….

Well there is stainless and stainless and there is welding and welding. 😉

Some modern new manufacture ‘stainless’ steel Spitfire stacks have given exceedingly good service, whilst clearly Warbird UK has a different experience.

Interestingly Karel Bos, the owner of Historic Flying Ltd., is also the owner and former CEO of Bosal one of the biggest suppliers of ‘Original Equipment’ exhaust systems to the Motor industry.

The problem with multi branch manifolds and exhaust systems for cars is that the ‘lesser’ steels have a greater ability to cope with stress and temperature cycles, with attendant cracking, than steels in the ‘stainless’ range. These problems can be developed out by ‘engineering’ for mainstream vehicles but for specialist cars such as the ‘Ginetta’ mentioned the budget is just not there.

Mark

I don’t know this is the reason, but stainless exhaust manifolds for cars have a tendency to crack. Apparently, the heat tolerance of stainless is lower than mild steel.
The term stainless steel covers quite a range of alloys and although there might be specialised high temperature ones, as I’m not a stainless expert I wouldn’t know.

That’s why I’ve just spent two or three years finding a mild steel manifold for my Ginetta.

Just a quickie, Stainless exhaust stubs don’t last as long as the steel ones.

warbirdUK
Please could you expand/explain why, as this does suprise me.

Just a quickie, Stainless exhaust stubs don’t last as long as the steel ones.
Cheers……………….

Yes, that type were fitted some while after the aeroplane was restored at HFL.

Earlier pictures wil show the type fitted to EP120 – its a correct Spitfire exhaust, and BM597’s earlier fit were the exhausts it had on when it was a gate guard.

But I prefer the flared ones!

Bruce

I think so…

One of my fave Spitfires 😀

Correct me if I’m wrong but doesn’t HAC’s BM597 have the correct fish tail type exhaust stubs for the MkV ?

Paul,

I’d go along with you there, I only said it was unusual not that I didn’t like it 😉

I’m looking forward to a few more “unusual” schemes this year, namely PV202 emerging as Irish Air Corps IAC-161 and Seafire SX336 as well a Seafire really…:D 😀