So simple in concept, so complicated in design, so magical in operation. The early engineers that created these marvels were geniuses and the calculations were all done with slide rules. Simply amazing. Thank you Secret Agent JayZed of the Imperial Space Command.
I'm on a production line for DS/SC (directional solidification, single crystal) blades and vanes. A lot of what you said regarding those is pretty accurate. Lost wax method, the patterns start as wax, get coated with ceramic (different material cores suspended within for hollow castings). the wax is autoclaved out, then metal poured into the now hollow ceramic mold. Cut all the castings apart from the mold after knocking the ceramic off, rough grind em, gauge em, grind em into tolerance if they're out. Then there are a plethora of processes and redundancies that I won't go into detail about out of fear for my job (sensitive government contracts) including acid etching, heat treat, xray to name a few, just to make sure the thing won't turn to shrapnel when its spinning-like-none-other next to your wing seat on a flight. The customer does the final milling and drilling and performs their own redundant checks. The refined and exacting process keeps the scrap rate as low as possible. The amount of criteria I look through on a daily basis to make sure a part is to-blueprint-spec is ungodly. I deal with defective parts that are cast in a way that's "kissed out" like the leading edge of the one at 7:45 dozens of times a day.
Once again you bring much joy to an old mans heart showing older tech to explain how we got from where we were to where we are. Watching the tech grow from the old J-33 to the J-35, to the J 47, J 57 etc, was quiet a feat in its time. Because of these evolutions in design, we now have very reliable and safe airplanes.
Yes, back in 1971, I watched that Industrial Olympus HP turbine blade being designed on the next drawing board by Alan C***, while I was designing the LP turbine blade. We actually made trips up to Derby from IMD Ansty, to use a a new computer program, which helped us to improve the aerofoil profile and give a smoother pressure/velocity distribution over the suction surface. And yes, I know there is no such thing as suction, but that's the standard terminology!
Laser holes had a natural roughness which supposedly helped with the cooling. EDM made a cleaner hole. Later EDM was used to create shaped holes, think of small NACA ducts. When I was at P&WA shaped holes could only be designed into military engines. Calculating the location of the holes was tricky due to the stack up of tolerances between the interior and exterior surfaces. The core mold could shift in relation exterior mold. I also saw an early graphic program that was used to figure out if a shaped tube could be inserted into a blade. The tube allowed better control of the air than a simple shaped hole.
I used to make them.. Ist hp blades for the RB199 Which powered the Pan Avia Tornado and Pegasus blades for the Harrier. Directionally cooled single crystal materials, cast hollow and cooling holes 10 thou apart and 10 thou(showing my age😂) dia. The leading edge holes were put in using EDM, the trailing edge holes with an acid etch comb. They were high density radiographed (x-rayed) to look for `Bladeworms` and misaligned holes. A single RB199 1st HP was said to produce the same power as a 2 litre engine.If they had a fine groove running down the leading edge they would have been a Gulf War mod. The Tornados extremely low altitude attacks meant the engines ingested a bit of very fine sand abraiding the leading edge. The groove disturbed the flow and pressure through the holes abated it somewhat. The Harrier could achieve supersonic only if we polished the blades....but they did go supersonic.
PPS The 'sand tolerant' HPT blade for the RB199 was designed for the Royal Saudi Air Force. Sand storms in Saudi Arabia can go as high as 10,000ft or more. The "sand" at that altitude is extremely fine, down to micron size - and I hear from a little bird at R-R that it's causing problems for airliners that operate regularly through that part of the world.
@beans oof No idea..but we`d get between 15/20 on a plate. It was high density radiography. i`ll assume it was a far more intense dose of radiation than you`d get at the hospital.
@beans oof The High Density Radiography was a different department to the blade shop. A lot of different components were x-rayed. We`d get batches of blades returned to us with the films attached. I recall the construction of the x-ray machines was pretty `monumental` and all the operators wore radiation tags. This was in the `70s they probably have much more compact equipment now.
A year or so ago, I watched a video on making the new Trent (I believe) engine and they discussed "growing a blade from a single crystal." They wouldn't explain how it was done as it was proprietary. That made no sense to me until you just explained how it's done. That's a pretty awesome use of technology. Thanks for all your work here Jay, I really enjoy learning about this technology.
Directionally solidified (DS) and single crystal (SX) blades are produced by controlling the solidification from root to tip. This is done by casting the blades in a small furnace, which is then withdrawn from around the still molten metal within its investment 'shell'. The growth of a single crystal can be initiated by having a narrow corkscrew form beneath the blade root. This encourages the growth of a single crystal through the corkscrew, which then progresses from the root of the blade to the tip.
Some years back, working as a contractor at P&W plants, I was amazed at what they did at their ACF (automated casting facility) in Middletown for making 1st stage turbine blades, for gas turbines & space shuttle turbo-pumps. They used lost-wax to make joined mold for 2 halves of blade. With the wax gone the combo mold went into huge evacuated chamber where nickel-hafnium was sputtered down from cylindrical ingot. After separation, the two half-blades were clamped in fixture, with punched-out sheet of same alloy at joining face, right about melting-point for a day or two. Net: mono-crystalline blade with precision cooling passages.
Thats pretty cool, I work for a mechanical seal manufacturer. We make face seals for rotational equipment that are flat to within 2 helium light bands total deviation over the surface, similar to the carbon oil seals that are used in these engines. We have gas compressor seals that run ultra dry nitrogen between the faces, and there are 10 micron deep impressions sintered into the silicon carbide that cause the faces to lift apart and form a non-contact seal. Extremely low drag and zero wear, they are used in enrichment centrifuges. They also use some type of mechanical seal on the turbo pump for a closed/combined cycle liquid rocket engine. Not as cool as working for pratt and whitney though :(
First off, excellent video. The amount of material science, engineering, and manufacturing knowledge that goes in to such a small portion of these engines is absolutely incredible. One of the more interesting material advancements that was not discussed is the development of nickel based super alloys - such as Rene 65 - for the first turbine stage of GE engines. These alloys are truly incredible, maintaining strength well beyond the temperature range of any other material. Going forward, the usage of metal additive manufacturing techniques is going be quite interesting. Not only due to the new geometries that will be capable of being produced, but also how engineers deal with residual stresses and the inherent microscopic flaws that the process produces.
We still use a version of lost wax casting, the "core" (which is the shape and size of finish part) is made in presses that use a ceramic material that is forced under heat and pressure to fill the die in the press much like aluminium die casting. Once this part goes thru the whole process it is a fragile ceramic part that goes to one of our casting houses which go thru the whole lost wax casting process. We are working on 3d printing at this time, it can make very intricate parts but at this stage it is very slow. At some point when the tech gets better you will see more print farms cropping up. Love your vids and stay safe out there!!
Working for a company that makes dressers for grinding these blades for 25 years…nice to actually see an explanation of how they all come together. I will recommend to coworkers.
I remember learning about single-crystal turbine blades back in engineering school. My university's mechanical engineering department at the time were doing a lot of R&D on machining the x-mas tree for the turbine roots.
Gas turbine blades are commonly made in directional solidification casting process to produce blades made from a single crystal of alloy. The hollow passages are created by small ceramic cores that the metal flows around. A blade takes hours to cast because the solidification is controlled to produce that single crystal. They are quite an engineering accomplishment.
I'm enjoying the heck out of your videos, you're very entertaining. I was a USAF jet engine mechanic back in the late 60's doing 1600 hour hot section inspections on J57-55s with AB and J57-59s with water injection. Then moved on to TF-33s and finally teeny GE85s in hueys. Also ran test cell. Neat memories of a long time ago. Thanks for sharing your tremendous knowledge.
I love this channel, as thank you for teaching me how to do the stainless wire twist, as used the techniques on my V8 range rover tubular heat wrap, as works perfectly
We use GE26 turbines at the power station I work at, that first GE blade you picked up looked similar to one of those blades. They have holes all the way down the leading edge and on the end of the tip, it's really interesting to look at!
If you had the time for it, it might be a fun project to get those old blades etched to bring out the grain structure. 13:11 The moulds for single crystal blade also have a pigtail shape in the bottom to make sure that only one crystal will grow through into the mould. They now even put a "seed" of metal in the bottom of the mould before they cast which has a known crystal orientation, so not only does the blade have a single crystal, the individual atoms in that crystal are all aligned along a certain plane which gives the best performance. Single crystal blades are interesting for another reason, grain boundaries give metal a lot of strength, almost every other application of metal aims to get the crystals as small as possible to get the best properties. It's only when you get to very high temperatures, near to the melting point, the grain boundaries suddenly turn into weak points. So it's a compromise, essentially the blades are made intentionally weaker than they could be, to get better properties in the very specific application of an engine turbine.
Love your video's..been watchin for several years...im just an average joe in mpls mn, however quite interesting info here to me...airplane engines like these are just so interesting...thanks for posting!!
@@stefanmolnapor910 ehh this winter's not bad sofar..few cold days then warms back into the mid 30's..here ..i can still work in my shed with no gloves(small engine repair)..thanks for the comment enjoy florida!!
And my informal education continues. So much to learn. "Jet turbine engine blade" seems to be the standard description on that site. Likely the average seller there struggles with technical descriptions. And I suppose this works because many buyers don't know the difference. Lack of knowledge is curable and it's always good to have an expert clarify things. Thanks again.
Great video! You have a lot of knowledge on blade design/development and manufacturing techniques. I’m a huge nerd in turbine blades and vanes those little components are engineered with so many variables taken into account, it is truly amazing. For a little over six years I have worked as a quality engineer at P&W as well as smaller suppliers solely working around blades and vanes. For your 3D printing question within the video I have a little bit of an answer. Printed blades are not produced for production engines as of yet. The parent material for blades are typically exotic materials where traditional FDM printing is not a viable option. I do know that there is significant research and effort presently to produce blades by printing but it seems we are not anywhere close to that being used as a manufacturing method. There are experimental blades that are printed but strictly for development types of application. If you have any question on these types of components I would be more than happy to answer what I know! Keep making these excellent videos my friend!
My oldest brother retired from PWA and was an electronics tech working on the lasers that made the single crystal blades. I worked Middletown PWA assembly for a couple years in the late 70s.
Years ago I did a sales visit to BAE in Filton. They had a neat test rig to look at blade cooling efficiency, they made scale models of the blades in clear plastic then fed air into them and looked at the airflow pattern etc. The models were about 5x bigger than the real ones.
I think that visit would have been to Rolls-Royce Bristol. Flow visualisation using 'Perspex' models was being done when I was an apprentice back in the 1960s. It can all be done on a computer now.
grahamj9101 Hi Yes sorry RR Bris, BMW were also involved. We supplied the mass air flow sensors for the test rig. We also supplied lots 😀 of ultrasonic fuel flow meters for the fuel test rigs! Sad to see it all shrinking now.
What I find with 3d Metal printing is that they come up with project that are built to "prove" they can do everything better, than standard techniques. But once you get into the detail of what their creation can do you realise it is significantly limited. All 3d Metal printers have to be heat treated and some often under the HIP (Hot isostatic pressing) process very much what is done with CNC Milling inserts. Basically re-meltng the part under pressure almost to melting and then regrowing the crystal boundaries into something that actually has strength. This is also a very high failure rate process. It can produce some geometries that are harder to do with castings if you have a mold producing your wax shape. However, what is often done is you simply print in wax with the same geometric fidelity, up to 20 micron accuracy, and then its even better than 3d metal printing because you have less warpage of parts. 3D metal printing is often printed a very thick, up to 3 inch thick, bases to stop the parts potatoe chipping (yep thats the phrase used) when they printed. So while they say its been completely 3D printed it didn't come out of the machine and onto the engine. This is what they leave out. And they also leave out that they threw away 8 of 10 parts and that there was alot of CMM work to figure out which ones were good. And if they say this geometry can only be 3D metal printed they don't tell you that 3D printed Lost wax can do it better because it doesn't need the HIP process. 3D metal printing is where computers were in the 1990s lots of smoke and mirrors to say they can do incredible things but really they are struggling to get there.
Has the Canadian Navy ever invited you aboard a ship to see a marine power plant and talk to the engine room ratings? I don't think I've ever seen such as I've worked my way through your years of output. I think that would make a pretty cool video. The frigates seem to have 2 LM 2500s and a diesel.
Back in 87 whist in college I spent some time at Deloro Stellite where one of the products made were stellite turbine blades which were cast using the lost wax process.
I've been making wax molds for investment castings since the 70's. I've seen that industry go through a lot of changes over 50 years. I've made blade molds, some big, some small. The one thing they all have in common is how accurate they have to be. When I started, the machines used to produce the molds were not computer controlled. We built models of the blades that were about 5 times larger and then used expensive German made pantographs that would reduce the model down to size. It worked but it was time consuming and very expensive. BTW, EDM machines have been around since before I came into the business 50 years ago. It's amazing what they have been adapted to do.
Why exactly is the yield output so low in casting turbine blades/vanes? I have worked every other process for these components but never had the experience to see the casting process.
Full size metal 3D printed turbine blades are used, but only for tooling and manufacturing trial purposes. The structure of the metal is not of high enough quality to withstand the stresses and temperatures of engine running. After the casting and cooling technologies, coating is the other key enabler to today's ultra high turbine temperatures. The next big step forward is CMCs (Ceramic Matric Composites). GE is already using these for blade shrouds in the LEAP engine and possibly HPT NGVs in the GE9X. HPT blades have been tested, but unlikely to be in production use. CMCs also need coating, but for slightly different reasons to nickel base alloys.
The first use of air cooled turbine blades was in some of the German engines during WWII. Nazi Germany didn't have access to sufficient supplies of nickel, etc, and had to resort to cooling fabricated stainless steel blades.
@AgentJayZ I don’t think we’re ever going to see 3D printed high pressure turbine blades because of the porousness, and lack of creep resistance, unlike a single crystal. However, 3D printing could be used to make wax molds for investment casting, especially for the internal cooling passages. You’d have to do something clever to get the outer surfaces of the blade nice and smooth, though. The holy grail of turbine materials that shifts to the right at the rate of about 12 months per year is ceramic matrix composites (CMCs). Same stuff as the Space Shuttle leading edges were made from. Great strength at very high temps, but they just can’t match the superlative toughness super alloys like you mentioned. On their latest engines, GE is using CMCs for combustors and nozzle guide vanes, but more development and service history is going to be needed before anyone makes turbine blades out of them.
A shop here has an EDM machine and the fluid IS water, which is common. Few people know it, but pure water is an insulator. The machine also has an elaborate water purifier and conductance measurement system.
I just watched the video where you pluck the turbines on a cross section. The tone is amazing. I just ordered one blade because this video made me want one really bad. Now I’m realizing a bunch of them would make an a great musical instrument. I’m only guessing the air cooled blades sound completely different. I don’t know. But these videos are inspiring on many levels. There was a time when I thought I’d never get a grasp on the basics of how a jet engine worked. Written descriptions didn’t give me a working mental model. But now I have an even greater appreciation with my better understanding. And a better appreciation for Canadians! Just kidding.
Those were compressor blades. Turbine blades will sound like rocks. There is an instrument out there that was made from a j79 compressor. It's called the Turbinophone, and it has its own internet presence. Have a quick search for it.
AgentJayZ Thanks, I’ll check it out. I want my own obviously. And the blades plucked in the video were outside for a long time and were stuck in place, thus the tone.
I'm amazed that alot of this was designed by hand on paper back in the 1930-40's without computers. Even the manufacturing back then is insane. After the 1st world war, the world really leaped ahead in time!
That Industrial Olympus HP turbine blade, which AgentJayZ showed us, was designed by hand, on paper, in 1971. I watched it happen, as I was on the next drawing board, designing the LP turbine blade. Drawing boards were in use into the 1990s. PS To be absolutely correct, we drew on plastic draughting film, not paper - and we did a lot of our calculations using a slide rule.
3D printing reintroduces problems associated with earlier polycrystaline blades. This is an issue for the hottest parts because of creep. It is possible to get quasi-directional grains in the build direction which may help. We can add tungsten, and some other elements to help at the grain boundaries. A recent paper even introduced nano powder yttria to great effect. However, single crystal currently remains the best method to maximizing the metallurgical properties of the blade.
i work at investment foundry where we cast these types of blades, we use only lost wax method, as far as i know right now there is no possibility to 3d print rotating engine parts because of the microporosity you get in that process, printed blades would not meet today's standards so they would be much weaker comparing to the cast ones
First British and Canadian blades were made of wrought alloys, such as nimonic series. (90 for the 14 I think) The North Americans also used forgings in the j47 and then castings. Orenda introduced the IN713 on the Iroquois, which is cast. An excellent alloy that is used to this day and very inexpensive. RR had been using forged blades for quite some time, even cooled, which was very expensive. The external holes were made with electrochemical milling. That technique is still used.
Always love your vids I know how turbine blades are made but never saw the inside of one absolutely amazing keep up the great work I'm always looking forward to your next vid one of your biggest fans madcat45
The dielectric fluid in the EDM process is to flush the swarf away, and keep the bubbles which contain hydrogen from igniting. Makes a scary mess if the fluid runs low. Or you forget to close the drain....But now I'm ready for that trick blade question!
I worked on 3D printed rocket engine parts. It's very expensive at this point and they still have be finish machined because the process is not quite accurate enough for a precision fit.
As far as I know there are 3D printed ceramic blades being developed but if they are already in production I don't know. Advanced ceramics are awesome because they can be cast as well and using an Isostatic/hydrostatic pressing followed by sintering process they cause the pores in the ceramic to close and turn into a glass like surface. Ceramics such as Aluminum Silicate have a very high melting point and VERY low heat absorption so the blades never even heat up to the point of failure. I think in the future they may combine metal and ceramic 3d printing because ceramics are very weak and you could include metal frames for strength while keeping the benefits of an all ceramic blade.
I might be wrong, but one outstanding characteristic for a turbine blade is that it has a slot in its base for the locking pin, while the compressor blade doesn't (as appears in the clip, the ones you showed us). But maybe they do have a locking pin for compressor blades as well?
There are many designs out there. The RR Avon secures each compressor blade to its disc with a large pin, which functions in a different way than these locking pins.
So highly interesting ! I learn a lot in your excellent videos !! And your "commenting skills" are always awesome. Best salutations from Quebec City, Canada.
A long while back, while doing Thermodynamics at Swinburne Uni in Melbourne, we analysed an Atar jet engine. From memory I think they had sodium filled blades. I think Atars came out of Mirage jets and were also used for peak hour electricity generation.
Why hand polishing, versus wirewheel/polisher/bufferwheel? And what media can be used for bead blast, glass, walnut shells, sand…? And where did your Avon (blade) come from, another Sabre jet? That was a big deal engine, Hawker Hunter (a fav), Fairey Delta (another fav), and EE Lightning - I hope to work on them on the Warbird circuit. And the Olympus…Like the Concorde Olympus?? Not the TSR2…??? (That would be priceless nowadays). Nice trophy.
I'm not sure that aircraft was their end destination, but Siemens has been developing (and to my knowledge have a few full-function ones in active use) 3D metal print machines to print parts for their steam turbine production facilities. I came across a few videos while looking at metal 3D printers to do a custom turbine profile for my big project. Desktop Metal also has some very high end machines that could print a multitude of aircraft parts in usable high nickel alloys and various stainless compositions, but the cost is, shall we say, business oriented. Their base machine is going for a cool 150K... Convenience ain't cheap!
Excellent work. Does CMC (ceramic material composite) blade fall in DS (directional solidification) category or single crystal blade? Also, on the table (near the blades), are they fuel pumps? Thanks for teaching us...
It's interesting how the compressor blade is formed at 11:40 because it's at an higer angle of attack at the tip than the root. With propellers, it's the opposite. The root is at an higer angle of attack, than the tip.
22:06 the machining here is just incredible. I mean I really appreciate 3d printing and the amazing things it's letting us do now, but jesus, there really will be an art lost when it basically replaces a lot of these complex machining methods.
Most of these blades are able to stand upright just on the narrow bottom. That shows nicely how the balancing was done so that the center of gravity, respectively the direction of the centrifugal force while in motion, runs straight through the middle of the piece, in order to stress the attachment evenly. I am sure many of the turbine lessons were learned by trial and error, and pushing the envelope.
Single Crystal is much, much stronger than 3D printing, 3D printed Turbine blades are not even on the horizon, yet, even for engines still on the drawing board. Much more likely to have blades made from ceramics (due to potential weight savings and heat resistance) than 3D printing. Ceramic blades would not need the intricate internal cooling schemes that metal blades require. Before someone brings up GE9X "3D printed TiAl LPT blades", TiAl ceramic is a FORGED material. GE is just 3D printing the blanks that go into the forging process to reduce the amount of material to be machined off. Don't believe the "3D printed" hype. For hole drilling, shaped cooling holes can now be made with LASER. Shaped cooling holes on parts made more than 10 years ago were all EDM. The ridge and color change around the Squealer tips on some of the blades (the CF6ish) ones indicate a previous tip weld repair.
Hey, I have an LM2500 blade identical to your extremely melted one, same markings and everything! Mine’s not melted but it does have damage to the blade tip from rubbing on the shroud
GE is currently building/using what they call Ceramic Matrix Composites in the combustor and possibly high pressure turbine stages of the LEAP series of engines. The idea is to use the temperature resistance of ceramic combined with the strength of more conventional metallic superalloys. As I understand it. Truthfully I havent payed very close attention to commercial aerospace in some time so by all means, do your own research. But its a good place to start.
I was reading recently that we now have the technology to emulate a crystal grain structure in 3d printed metal - giving you the ability to control the grain size and orientation. That is very interesting (they're called "meta-crystals" if you'd like to check it out). If it is possible to be stronger than single crystal, 3d metal parts would require this kind of manufacturing technique.
Exelent description Sir ! Why all the effort to cool the turbine blades? Because modern engines have higher combustion temperatures so that they achieve better efficiency? Can a richer mixture also achieve a cooling effect? Why did the first engines produce so much smoke? Like General Electric's J-79 or the Rolls Royce Avon. Very good site here, thumbs up and subscribed.....greetings from Germany !
Combustion temp has always been the same... very high. The mixture made up of combustion gases and cooling air needs to be as hot as possible for good power. For decades the turbine entry temp has been higher than the melting point of the metal in the turbine blades. Active cooling is the only way to keep the blades from melting.
Very good point ! The accumulation of sand and dust inside turbine blades is a well known concern amont jet engine manufacturers. As a partial answer based on my knowledge of CFM jet engines, there isn't usually a device that filters the air beforehand. Some patents exist but I don't know any engine that has such devices (maybe AJZ can help us with that). However, on rotating turbine blades, there are usually holes with a larger diameter at the tip of the blades which allow sand and dust particules to escape. You have one large hole for each cavities.
I work for a company that gets casting of solid and vented blades and vanes. We use milling, EDM and grinders to bring them to their final shape for the customer. Some of the parts have as many as 30 operations before they leave for the customer.
Hey agent J, I found the wreckage of a B-57 hustler. # 61-2056, upon searching for anything cool, I found a few of what looks like hot section fins. However I also found one blade that had what looks like cooling air duct holes. I didn’t think the J79s from that time had any air cooled blades?
There is/was no such thing as a B57 Hustler. Sure, it's only one digit, but it calls into question your accuracy for other details. For example, there are no parts called fins anywhere in a J79. If you did find the wreckage of an aircraft, a very interesting find would be even a picture of an engine data plate. Cooling air holes in a turbine blade confirms the engine to be something other than any J79.
I work for a metal 3D printing company. I have only been with them a short time. It is amazing what can be printed. There is a turbine blade in the display case in the lobby I will see if I can snap some pictures of it.
Cool. Just relaxing and boom. Your videos popped up. Great timing. Sure I will enjoy. Thanks for sharing. I wonder what the Rockwell C value are on the different blades throughout the years? Is the hardness constant throughout? Good job.
@@AgentJayZ During the early development of the jet engine, when an inventor created something like a jet fin, he did not disclose it to others specially during the start of its development. Is it not? They patent it and keep the manufacturing process secret. Maybe you are talking about nowadays.
So simple in concept, so complicated in design, so magical in operation.
The early engineers that created these marvels were geniuses and the calculations were all done with slide rules.
Simply amazing. Thank you Secret Agent JayZed of the Imperial Space Command.
I'm on a production line for DS/SC (directional solidification, single crystal) blades and vanes. A lot of what you said regarding those is pretty accurate. Lost wax method, the patterns start as wax, get coated with ceramic (different material cores suspended within for hollow castings). the wax is autoclaved out, then metal poured into the now hollow ceramic mold. Cut all the castings apart from the mold after knocking the ceramic off, rough grind em, gauge em, grind em into tolerance if they're out. Then there are a plethora of processes and redundancies that I won't go into detail about out of fear for my job (sensitive government contracts) including acid etching, heat treat, xray to name a few, just to make sure the thing won't turn to shrapnel when its spinning-like-none-other next to your wing seat on a flight. The customer does the final milling and drilling and performs their own redundant checks. The refined and exacting process keeps the scrap rate as low as possible. The amount of criteria I look through on a daily basis to make sure a part is to-blueprint-spec is ungodly. I deal with defective parts that are cast in a way that's "kissed out" like the leading edge of the one at 7:45 dozens of times a day.
hi logic i sent u some email becoz of ur exprience check it up thank you.
Once again you bring much joy to an old mans heart showing older tech to explain how we got from where we were to where we are. Watching the tech grow from the old J-33 to the J-35, to the J 47, J 57 etc, was quiet a feat in its time. Because of these evolutions in design, we now have very reliable and safe airplanes.
Yes, back in 1971, I watched that Industrial Olympus HP turbine blade being designed on the next drawing board by Alan C***, while I was designing the LP turbine blade. We actually made trips up to Derby from IMD Ansty, to use a a new computer program, which helped us to improve the aerofoil profile and give a smoother pressure/velocity distribution over the suction surface. And yes, I know there is no such thing as suction, but that's the standard terminology!
Laser holes had a natural roughness which supposedly helped with the cooling. EDM made a cleaner hole. Later EDM was used to create shaped holes, think of small NACA ducts. When I was at P&WA shaped holes could only be designed into military engines. Calculating the location of the holes was tricky due to the stack up of tolerances between the interior and exterior surfaces. The core mold could shift in relation exterior mold.
I also saw an early graphic program that was used to figure out if a shaped tube could be inserted into a blade. The tube allowed better control of the air than a simple shaped hole.
I used to make them.. Ist hp blades for the RB199 Which powered the Pan Avia Tornado and Pegasus blades for the Harrier. Directionally cooled single crystal materials, cast hollow and cooling holes 10 thou apart and 10 thou(showing my age😂) dia. The leading edge holes were put in using EDM, the trailing edge holes with an acid etch comb. They were high density radiographed (x-rayed) to look for `Bladeworms` and misaligned holes. A single RB199 1st HP was said to produce the same power as a 2 litre engine.If they had a fine groove running down the leading edge they would have been a Gulf War mod. The Tornados extremely low altitude attacks meant the engines ingested a bit of very fine sand abraiding the leading edge. The groove disturbed the flow and pressure through the holes abated it somewhat.
The Harrier could achieve supersonic only if we polished the blades....but they did go supersonic.
AgentJayZ has a couple of RB199 HPT blades: I sent them to him.
PS I was responsible for the design of the so-called 'sand tolerant' HPT blade for the RB199.
PPS The 'sand tolerant' HPT blade for the RB199 was designed for the Royal Saudi Air Force. Sand storms in Saudi Arabia can go as high as 10,000ft or more. The "sand" at that altitude is extremely fine, down to micron size - and I hear from a little bird at R-R that it's causing problems for airliners that operate regularly through that part of the world.
@beans oof No idea..but we`d get between 15/20 on a plate. It was high density radiography. i`ll assume it was a far more intense dose of radiation than you`d get at the hospital.
@beans oof The High Density Radiography was a different department to the blade shop. A lot of different components were x-rayed. We`d get batches of blades returned to us with the films attached. I recall the construction of the x-ray machines was pretty `monumental` and all the operators wore radiation tags. This was in the `70s they probably have much more compact equipment now.
I'm a sheet metal guy of a decade and my head just exploded. That's some in-depth metallurgical information there.
A year or so ago, I watched a video on making the new Trent (I believe) engine and they discussed "growing a blade from a single crystal." They wouldn't explain how it was done as it was proprietary. That made no sense to me until you just explained how it's done. That's a pretty awesome use of technology. Thanks for all your work here Jay, I really enjoy learning about this technology.
Directionally solidified (DS) and single crystal (SX) blades are produced by controlling the solidification from root to tip. This is done by casting the blades in a small furnace, which is then withdrawn from around the still molten metal within its investment 'shell'. The growth of a single crystal can be initiated by having a narrow corkscrew form beneath the blade root. This encourages the growth of a single crystal through the corkscrew, which then progresses from the root of the blade to the tip.
Some years back, working as a contractor at P&W plants, I was amazed at what they did at their ACF (automated casting facility) in Middletown for making 1st stage turbine blades, for gas turbines & space shuttle turbo-pumps. They used lost-wax to make joined mold for 2 halves of blade. With the wax gone the combo mold went into huge evacuated chamber where nickel-hafnium was sputtered down from cylindrical ingot. After separation, the two half-blades were clamped in fixture, with punched-out sheet of same alloy at joining face, right about melting-point for a day or two. Net: mono-crystalline blade with precision cooling passages.
Thats pretty cool, I work for a mechanical seal manufacturer. We make face seals for rotational equipment that are flat to within 2 helium light bands total deviation over the surface, similar to the carbon oil seals that are used in these engines. We have gas compressor seals that run ultra dry nitrogen between the faces, and there are 10 micron deep impressions sintered into the silicon carbide that cause the faces to lift apart and form a non-contact seal. Extremely low drag and zero wear, they are used in enrichment centrifuges. They also use some type of mechanical seal on the turbo pump for a closed/combined cycle liquid rocket engine. Not as cool as working for pratt and whitney though :(
Middle Town PA or Middle Town CT ? I work at the plant in PA
@@AlChemicalLife The one with the ACF, Middletown CT, 35 yrs back.
First off, excellent video. The amount of material science, engineering, and manufacturing knowledge that goes in to such a small portion of these engines is absolutely incredible. One of the more interesting material advancements that was not discussed is the development of nickel based super alloys - such as Rene 65 - for the first turbine stage of GE engines. These alloys are truly incredible, maintaining strength well beyond the temperature range of any other material. Going forward, the usage of metal additive manufacturing techniques is going be quite interesting. Not only due to the new geometries that will be capable of being produced, but also how engineers deal with residual stresses and the inherent microscopic flaws that the process produces.
Another amazing video with lots of technical detail. Love these! Going on 6 years of watching your videos!
We still use a version of lost wax casting, the "core" (which is the shape and size of finish part) is made in presses that use a ceramic material that is forced under heat and pressure to fill the die in the press much like aluminium die casting. Once this part goes thru the whole process it is a fragile ceramic part that goes to one of our casting houses which go thru the whole lost wax casting process. We are working on 3d printing at this time, it can make very intricate parts but at this stage it is very slow. At some point when the tech gets better you will see more print farms cropping up. Love your vids and stay safe out there!!
Working for a company that makes dressers for grinding these blades for 25 years…nice to actually see an explanation of how they all come together. I will recommend to coworkers.
I remember learning about single-crystal turbine blades back in engineering school. My university's mechanical engineering department at the time were doing a lot of R&D on machining the x-mas tree for the turbine roots.
I don't remember how I found this channel but the amount of useless (to me) info I have learned about Jet turbine engines is nuts. Dope ass channel
It's the way you used (!) the word "useless" that really got my attention here...
Gas turbine blades are commonly made in directional solidification casting process to produce blades made from a single crystal of alloy.
The hollow passages are created by small ceramic cores that the metal flows around. A blade takes hours to cast because the solidification is controlled to produce that single crystal. They are quite an engineering accomplishment.
Sounds like the blades are designed for Acoustic resonance resistance... -:)
I'm enjoying the heck out of your videos, you're very entertaining. I was a USAF jet engine mechanic back in the late 60's doing 1600 hour hot section inspections on J57-55s with AB and J57-59s with water injection. Then moved on to TF-33s and finally teeny GE85s in hueys. Also ran test cell. Neat memories of a long time ago. Thanks for sharing your tremendous knowledge.
Great to hear from real jet people!
Amazing that you did that cutaway so well. Thanks for the video.
Each time I see one of your videos, I learn more about turbines and how they are design. So thank you so much for making this videos
For those who interested in the Electrical Discharge Machining, there's a channel Applied Science that has an excellent video about that.
I love this channel, as thank you for teaching me how to do the stainless wire twist, as used the techniques on my V8 range rover tubular heat wrap, as works perfectly
We use GE26 turbines at the power station I work at, that first GE blade you picked up looked similar to one of those blades. They have holes all the way down the leading edge and on the end of the tip, it's really interesting to look at!
Thank you for having us.
thank you for showing us this and explaining. Very interesting stuff!
As a mechanic, I can watch this stuff all night long!👍
If you had the time for it, it might be a fun project to get those old blades etched to bring out the grain structure.
13:11 The moulds for single crystal blade also have a pigtail shape in the bottom to make sure that only one crystal will grow through into the mould.
They now even put a "seed" of metal in the bottom of the mould before they cast which has a known crystal orientation, so not only does the blade have a single crystal, the individual atoms in that crystal are all aligned along a certain plane which gives the best performance.
Single crystal blades are interesting for another reason, grain boundaries give metal a lot of strength, almost every other application of metal aims to get the crystals as small as possible to get the best properties. It's only when you get to very high temperatures, near to the melting point, the grain boundaries suddenly turn into weak points.
So it's a compromise, essentially the blades are made intentionally weaker than they could be, to get better properties in the very specific application of an engine turbine.
Love your video's..been watchin for several years...im just an average joe in mpls mn, however quite interesting info here to me...airplane engines like these are just so interesting...thanks for posting!!
I Grew up at Flemming field in s.s.p / inver grove! Hope your staying warm! I moved to FL!
@@stefanmolnapor910 ehh this winter's not bad sofar..few cold days then warms back into the mid 30's..here ..i can still work in my shed with no gloves(small engine repair)..thanks for the comment enjoy florida!!
@@leeharris3061 good! Sounds like fun! I miss the summers there! Take care Sir!
Thanks AGZ...turbine engines are fascinating, you do a great job explaining things.
You leave me curious about the state of that Orenda 10. It sounds like an interesting story to follow. Thanks for taking the time to share.
And my informal education continues. So much to learn.
"Jet turbine engine blade" seems to be the standard description on that site. Likely the average seller there struggles with technical descriptions. And I suppose this works because many buyers don't know the difference. Lack of knowledge is curable and it's always good to have an expert clarify things. Thanks again.
Actually just got a job making blades for P&W.. Pretty cool video !
Great video! You have a lot of knowledge on blade design/development and manufacturing techniques.
I’m a huge nerd in turbine blades and vanes those little components are engineered with so many variables taken into account, it is truly amazing. For a little over six years I have worked as a quality engineer at P&W as well as smaller suppliers solely working around blades and vanes.
For your 3D printing question within the video I have a little bit of an answer. Printed blades are not produced for production engines as of yet. The parent material for blades are typically exotic materials where traditional FDM printing is not a viable option. I do know that there is significant research and effort presently to produce blades by printing but it seems we are not anywhere close to that being used as a manufacturing method. There are experimental blades that are printed but strictly for development types of application.
If you have any question on these types of components I would be more than happy to answer what I know! Keep making these excellent videos my friend!
My oldest brother retired from PWA and was an electronics tech working on the lasers that made the single crystal blades. I worked Middletown PWA assembly for a couple years in the late 70s.
Years ago I did a sales visit to BAE in Filton. They had a neat test rig to look at blade cooling efficiency, they made scale models of the blades in clear plastic then fed air into them and looked at the airflow pattern etc. The models were about 5x bigger than the real ones.
I think that visit would have been to Rolls-Royce Bristol. Flow visualisation using 'Perspex' models was being done when I was an apprentice back in the 1960s. It can all be done on a computer now.
grahamj9101 Hi Yes sorry RR Bris, BMW were also involved. We supplied the mass air flow sensors for the test rig. We also supplied lots 😀 of ultrasonic fuel flow meters for the fuel test rigs! Sad to see it all shrinking now.
What I find with 3d Metal printing is that they come up with project that are built to "prove" they can do everything better, than standard techniques. But once you get into the detail of what their creation can do you realise it is significantly limited. All 3d Metal printers have to be heat treated and some often under the HIP (Hot isostatic pressing) process very much what is done with CNC Milling inserts. Basically re-meltng the part under pressure almost to melting and then regrowing the crystal boundaries into something that actually has strength. This is also a very high failure rate process. It can produce some geometries that are harder to do with castings if you have a mold producing your wax shape. However, what is often done is you simply print in wax with the same geometric fidelity, up to 20 micron accuracy, and then its even better than 3d metal printing because you have less warpage of parts. 3D metal printing is often printed a very thick, up to 3 inch thick, bases to stop the parts potatoe chipping (yep thats the phrase used) when they printed. So while they say its been completely 3D printed it didn't come out of the machine and onto the engine. This is what they leave out. And they also leave out that they threw away 8 of 10 parts and that there was alot of CMM work to figure out which ones were good. And if they say this geometry can only be 3D metal printed they don't tell you that 3D printed Lost wax can do it better because it doesn't need the HIP process. 3D metal printing is where computers were in the 1990s lots of smoke and mirrors to say they can do incredible things but really they are struggling to get there.
excellent video, thanks for your time
Has the Canadian Navy ever invited you aboard a ship to see a marine power plant and talk to the engine room ratings? I don't think I've ever seen such as I've worked my way through your years of output. I think that would make a pretty cool video. The frigates seem to have 2 LM 2500s and a diesel.
As a LAME, I can see you live and breath your work with a true passion. You my friend, is what our industry lacks. Keep up the good work!
Back in 87 whist in college I spent some time at Deloro Stellite where one of the products made were stellite turbine blades which were cast using the lost wax process.
I've been making wax molds for investment castings since the 70's. I've seen that industry go through a lot of changes over 50 years. I've made blade molds, some big, some small. The one thing they all have in common is how accurate they have to be. When I started, the machines used to produce the molds were not computer controlled. We built models of the blades that were about 5 times larger and then used expensive German made pantographs that would reduce the model down to size. It worked but it was time consuming and very expensive. BTW, EDM machines have been around since before I came into the business 50 years ago. It's amazing what they have been adapted to do.
Why exactly is the yield output so low in casting turbine blades/vanes? I have worked every other process for these components but never had the experience to see the casting process.
Full size metal 3D printed turbine blades are used, but only for tooling and manufacturing trial purposes. The structure of the metal is not of high enough quality to withstand the stresses and temperatures of engine running.
After the casting and cooling technologies, coating is the other key enabler to today's ultra high turbine temperatures.
The next big step forward is CMCs (Ceramic Matric Composites). GE is already using these for blade shrouds in the LEAP engine and possibly HPT NGVs in the GE9X. HPT blades have been tested, but unlikely to be in production use. CMCs also need coating, but for slightly different reasons to nickel base alloys.
I think the first use of air cooled blades was in the GE YJ-93 engine that was used in the XB-70
The first use of air cooled turbine blades was in some of the German engines during WWII. Nazi Germany didn't have access to sufficient supplies of nickel, etc, and had to resort to cooling fabricated stainless steel blades.
@AgentJayZ I don’t think we’re ever going to see 3D printed high pressure turbine blades because of the porousness, and lack of creep resistance, unlike a single crystal. However, 3D printing could be used to make wax molds for investment casting, especially for the internal cooling passages. You’d have to do something clever to get the outer surfaces of the blade nice and smooth, though.
The holy grail of turbine materials that shifts to the right at the rate of about 12 months per year is ceramic matrix composites (CMCs). Same stuff as the Space Shuttle leading edges were made from. Great strength at very high temps, but they just can’t match the superlative toughness super alloys like you mentioned. On their latest engines, GE is using CMCs for combustors and nozzle guide vanes, but more development and service history is going to be needed before anyone makes turbine blades out of them.
A shop here has an EDM machine and the fluid IS water, which is common. Few people know it, but pure water is an insulator. The machine also has an elaborate water purifier and conductance measurement system.
Anything can be used as a working fluid just as long as it is a dielectric.
Finally you post new video. This is super nice info, thank you for sharing with us. I appreciate it.
Interesting to see the air cooled holes. Dam expensive. Thanks for explanation
I just watched the video where you pluck the turbines on a cross section. The tone is amazing. I just ordered one blade because this video made me want one really bad. Now I’m realizing a bunch of them would make an a great musical instrument.
I’m only guessing the air cooled blades sound completely different. I don’t know. But these videos are inspiring on many levels.
There was a time when I thought I’d never get a grasp on the basics of how a jet engine worked. Written descriptions didn’t give me a working mental model. But now I have an even greater appreciation with my better understanding.
And a better appreciation for Canadians! Just kidding.
Those were compressor blades. Turbine blades will sound like rocks.
There is an instrument out there that was made from a j79 compressor. It's called the Turbinophone, and it has its own internet presence. Have a quick search for it.
AgentJayZ Thanks, I’ll check it out. I want my own obviously. And the blades plucked in the video were outside for a long time and were stuck in place, thus the tone.
We got rotors for free... if you handle the shipping. They show up in the scrap bin once in a while. They weigh about 500 lbs. Get on the list today!
AgentJayZ wow, 500 lbs from Canada might be a little too pricey at the moment but at some point or something smaller. Where’s the list?
They only come in one size.
I'm amazed that alot of this was designed by hand on paper back in the 1930-40's without computers. Even the manufacturing back then is insane.
After the 1st world war, the world really leaped ahead in time!
That Industrial Olympus HP turbine blade, which AgentJayZ showed us, was designed by hand, on paper, in 1971. I watched it happen, as I was on the next drawing board, designing the LP turbine blade. Drawing boards were in use into the 1990s.
PS To be absolutely correct, we drew on plastic draughting film, not paper - and we did a lot of our calculations using a slide rule.
@@grahamj9101 Good on you, that's awesome!
Another fact filled bag of goodies from AgentJayZ. With every post I learn more. Good stuff.
Thank you, professor Z.
3D printing reintroduces problems associated with earlier polycrystaline blades. This is an issue for the hottest parts because of creep. It is possible to get quasi-directional grains in the build direction which may help. We can add tungsten, and some other elements to help at the grain boundaries. A recent paper even introduced nano powder yttria to great effect. However, single crystal currently remains the best method to maximizing the metallurgical properties of the blade.
So cool, very interesting, more videos about turbine blade please
i work at investment foundry where we cast these types of blades, we use only lost wax method, as far as i know right now there is no possibility to 3d print rotating engine parts because of the microporosity you get in that process, printed blades would not meet today's standards so they would be much weaker comparing to the cast ones
Another great and well explained video 👍
Nowadays, 5 axis CNC machines are also used to make blades, quite a few videos on RUclips
First British and Canadian blades were made of wrought alloys, such as nimonic series. (90 for the 14 I think) The North Americans also used forgings in the j47 and then castings. Orenda introduced the IN713 on the Iroquois, which is cast. An excellent alloy that is used to this day and very inexpensive. RR had been using forged blades for quite some time, even cooled, which was very expensive. The external holes were made with electrochemical milling. That technique is still used.
The only 3D printer, commerical compressor blades can be found in GE's neu 9X. The blades are made of TiAl ceramic in an Arcam Spectra H 3D printer.
That wax method is called investment casting and generally used to cast complex shape materials.
Always love your vids I know how turbine blades are made but never saw the inside of one absolutely amazing keep up the great work I'm always looking forward to your next vid one of your biggest fans madcat45
The dielectric fluid in the EDM process is to flush the swarf away, and keep the bubbles which contain hydrogen from igniting. Makes a scary mess if the fluid runs low. Or you forget to close the drain....But now I'm ready for that trick blade question!
I worked on 3D printed rocket engine parts. It's very expensive at this point and they still have be finish machined because the process is not quite accurate enough for a precision fit.
you are an awesome teacher!!!!
As far as I know there are 3D printed ceramic blades being developed but if they are already in production I don't know. Advanced ceramics are awesome because they can be cast as well and using an Isostatic/hydrostatic pressing followed by sintering process they cause the pores in the ceramic to close and turn into a glass like surface. Ceramics such as Aluminum Silicate have a very high melting point and VERY low heat absorption so the blades never even heat up to the point of failure.
I think in the future they may combine metal and ceramic 3d printing because ceramics are very weak and you could include metal frames for strength while keeping the benefits of an all ceramic blade.
Great info here, spot on!
I might be wrong, but one outstanding characteristic for a turbine blade is that it has a slot in its base for the locking pin, while the compressor blade doesn't (as appears in the clip, the ones you showed us). But maybe they do have a locking pin for compressor blades as well?
There are many designs out there. The RR Avon secures each compressor blade to its disc with a large pin, which functions in a different way than these locking pins.
Fantastic video! Thanks for taking the time to share these beautiful works of engineering with us 🙂
So highly interesting ! I learn a lot in your excellent videos !!
And your "commenting skills" are always awesome.
Best salutations from Quebec City, Canada.
As usual ... FANTASTIC. Thank you!
Awesome video! Such an interesting topic. Thanks!
can you introduce more about turbine blade defects, how many types, what are the typical defects and root cause?
A long while back, while doing Thermodynamics at Swinburne Uni in Melbourne, we analysed an Atar jet engine. From memory I think they had sodium filled blades. I think Atars came out of Mirage jets and were also used for peak hour electricity generation.
great video again!
Why hand polishing, versus wirewheel/polisher/bufferwheel? And what media can be used for bead blast, glass, walnut shells, sand…?
And where did your Avon (blade) come from, another Sabre jet? That was a big deal engine, Hawker Hunter (a fav), Fairey Delta (another fav), and EE Lightning - I hope to work on them on the Warbird circuit. And the Olympus…Like the Concorde Olympus?? Not the TSR2…??? (That would be priceless nowadays). Nice trophy.
Yes, I too am often buying turbine blades on eBay 😂
Helluva shop, very interesting.
Great video 👍 neat stuff 🤤
Awsome topic! Thx J!
I'm not sure that aircraft was their end destination, but Siemens has been developing (and to my knowledge have a few full-function ones in active use) 3D metal print machines to print parts for their steam turbine production facilities. I came across a few videos while looking at metal 3D printers to do a custom turbine profile for my big project. Desktop Metal also has some very high end machines that could print a multitude of aircraft parts in usable high nickel alloys and various stainless compositions, but the cost is, shall we say, business oriented. Their base machine is going for a cool 150K... Convenience ain't cheap!
Excellent work. Does CMC (ceramic material composite) blade fall in DS (directional solidification) category or single crystal blade? Also, on the table (near the blades), are they fuel pumps?
Thanks for teaching us...
Beautiful description...I love your videos
It's interesting how the compressor blade is formed at 11:40 because it's at an higer angle of attack at the tip than the root. With propellers, it's the opposite. The root is at an higer angle of attack, than the tip.
Industrial gems! Priceless. Thanks.
22:06 the machining here is just incredible. I mean I really appreciate 3d printing and the amazing things it's letting us do now, but jesus, there really will be an art lost when it basically replaces a lot of these complex machining methods.
Most of these blades are able to stand upright just on the narrow bottom. That shows nicely how the balancing was done so that the center of gravity, respectively the direction of the centrifugal force while in motion, runs straight through the middle of the piece, in order to stress the attachment evenly. I am sure many of the turbine lessons were learned by trial and error, and pushing the envelope.
Single Crystal is much, much stronger than 3D printing, 3D printed Turbine blades are not even on the horizon, yet, even for engines still on the drawing board. Much more likely to have blades made from ceramics (due to potential weight savings and heat resistance) than 3D printing. Ceramic blades would not need the intricate internal cooling schemes that metal blades require.
Before someone brings up GE9X "3D printed TiAl LPT blades", TiAl ceramic is a FORGED material. GE is just 3D printing the blanks that go into the forging process to reduce the amount of material to be machined off. Don't believe the "3D printed" hype.
For hole drilling, shaped cooling holes can now be made with LASER. Shaped cooling holes on parts made more than 10 years ago were all EDM.
The ridge and color change around the Squealer tips on some of the blades (the CF6ish) ones indicate a previous tip weld repair.
Hey, I have an LM2500 blade identical to your extremely melted one, same markings and everything! Mine’s not melted but it does have damage to the blade tip from rubbing on the shroud
Have there ever been sintered silicon carbide blades? Or other ceramic like materiel?
GE is currently building/using what they call Ceramic Matrix Composites in the combustor and possibly high pressure turbine stages of the LEAP series of engines. The idea is to use the temperature resistance of ceramic combined with the strength of more conventional metallic superalloys. As I understand it. Truthfully I havent payed very close attention to commercial aerospace in some time so by all means, do your own research. But its a good place to start.
Awesome video JayZ - good stuff! Thank you for this and the other videos you post
I was reading recently that we now have the technology to emulate a crystal grain structure in 3d printed metal - giving you the ability to control the grain size and orientation. That is very interesting (they're called "meta-crystals" if you'd like to check it out). If it is possible to be stronger than single crystal, 3d metal parts would require this kind of manufacturing technique.
Exelent description Sir !
Why all the effort to cool the turbine blades?
Because modern engines have higher combustion temperatures so that they achieve better efficiency?
Can a richer mixture also achieve a cooling effect?
Why did the first engines produce so much smoke? Like General Electric's J-79
or the Rolls Royce Avon.
Very good site here, thumbs up and subscribed.....greetings from Germany !
Combustion temp has always been the same... very high.
The mixture made up of combustion gases and cooling air needs to be as hot as possible for good power. For decades the turbine entry temp has been higher than the melting point of the metal in the turbine blades. Active cooling is the only way to keep the blades from melting.
Question: Those cooling air holes in the turbine blades are pretty small... do they filter the air before 'injecting'?
We're going to need a video to answer that. Stand by.
@@AgentJayZ Nice work AJZ
Very good point ! The accumulation of sand and dust inside turbine blades is a well known concern amont jet engine manufacturers.
As a partial answer based on my knowledge of CFM jet engines, there isn't usually a device that filters the air beforehand. Some patents exist but I don't know any engine that has such devices (maybe AJZ can help us with that).
However, on rotating turbine blades, there are usually holes with a larger diameter at the tip of the blades which allow sand and dust particules to escape. You have one large hole for each cavities.
@@TrafalgarDLaw do u have information about the this blades?
GE's CMC (ceramic matrix composite) are 3D printed then grown to make what ever carbide required.
GE is working on silicon carbide turbine blades. Silicon carbide is used for foundry crucibles, very high refractory material
I work for a company that gets casting of solid and vented blades and vanes. We use milling, EDM and grinders to bring them to their final shape for the customer. Some of the parts have as many as 30 operations before they leave for the customer.
Hey agent J, I found the wreckage of a B-57 hustler. # 61-2056, upon searching for anything cool, I found a few of what looks like hot section fins. However I also found one blade that had what looks like cooling air duct holes. I didn’t think the J79s from that time had any air cooled blades?
There is/was no such thing as a B57 Hustler. Sure, it's only one digit, but it calls into question your accuracy for other details.
For example, there are no parts called fins anywhere in a J79.
If you did find the wreckage of an aircraft, a very interesting find would be even a picture of an engine data plate.
Cooling air holes in a turbine blade confirms the engine to be something other than any J79.
blades rubbing against the shroud?
that's fine it's just automatic clearance adjustment
like an automatic drum brake adjuster
Love the explanation of the manufacturing and design of these blades. Appreciate you taking the time.
I work for a metal 3D printing company. I have only been with them a short time. It is amazing what can be printed. There is a turbine blade in the display case in the lobby I will see if I can snap some pictures of it.
Ask if they have any rejects that they could send me!
@@AgentJayZ I will see what I can do.
@@AgentJayZ no rejects. The part is a piece from the printer company. Do you have an email address I can send some pics to?
TEİ (Turkish Company) have done the 3d printed turbine blades and combastion chambers and started the jet motor. This is the first time in the world.
Cool.
Just relaxing and boom. Your videos popped up. Great timing. Sure I will enjoy. Thanks for sharing. I wonder what the Rockwell C value are on the different blades throughout the years? Is the hardness constant throughout?
Good job.
These info used to be top secrets in manufacturing those fins.
No fins anywhere.
@@AgentJayZ During the early development of the jet engine, when an inventor created something like a jet fin, he did not disclose it to others specially during the start of its development. Is it not? They patent it and keep the manufacturing process secret. Maybe you are talking about nowadays.
There's still secrets as far as planning and operations especially in defense contracting
I really like this vid, a lot of good info some info is vague but accurate
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Very, very interesting! You are awesome!