Turbine Blade Production Techniques

As turbine blades have become more complicated, their manufacture has gone through some changes.

[todddembsky]

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.

[Dave-tyqp]

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.

[MarcusWolfWanders]

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.

[sillykanji]

I'm a sheet metal guy of a decade and my head just exploded. That's some in-depth metallurgical information there.

[crooked]

His voice and the way he explains it is the reason I watch this channel. I know only what he explained about engines and planes and this information is living rent free in my brain.

[grahamj]

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!

[engineerlyfe]

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.

[richglenn]

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.

[marshie]

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

[flyndoug]

Another amazing video with lots of technical detail. Love these! Going on 6 years of watching your videos!

[stephaniesinger]

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.

[philr]

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!!

[opler]

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.

[jacquesblaque]

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.

[deangiacopassi]

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.

[julioramirez]

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

[forestfishburne]

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.

[flt]

Amazing that you did that cutaway so well. Thanks for the video.

[wickedcabinboy]

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.

[sam_mcl]

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!