to reply to your question, as well as Robert's... it's the thermal difference that we need to use. Sometimes it is easier to chill one part instead of heating the other. Not so in this case. Also, chilling bearings or other parts can cause a lot of condensation of water onto them. This is the reason we would heat a housing, for example, instead of cooling the bearing going into it.
In Viet Nam, the J79 was routinely replaced in aircraft such as the Phantom II every 200 hours. Subjected to the stresses of combat, many were replaced at every 100 hours. Sheesh! It takes thousands of hours to overhaul one...
Our cold chamber is out the door at -25C... but bringing the cold part inside makes water condense on it. Also, as can be seen in this video, the oven created a sufficient temp difference that cooling the shaft was not necessary.
If we back up just a little bit, and remember this is an engine out of a 60 year old fighter, we might be more inclined to believe the maintenance schedule printed in the engine overhaul manual, where it says replace thrust bearing assembly every 400 hours. You're free to debate with the OEM manual, but I don't do that.
Turbine engines are commonly described as having a hot section and a cold section, but there is also a "warm" section, which is the shaft and associated machinery that passes through the hot section, but is not exposed to hot gas flow, and is both air and oil cooled. This is where the thrust bearing lives, and the temps in this area are usually kept below 400F. ...many hundreds of degrees below heat-treating temps.
Tapered rollers are optimized for one direction of axial load, and they are great at very high loads and moderate speeds. Deep groove ball bearings are better at handling loads in both axial diractions, and are better at moderate loads and high speeds. I could go on and on, but my comments about bearings always invite great criticism. Which I want to avoid.
6:30 So fun to see the SKF made these military quality ball bearings even all the back in 1962! SKF as we all know is Swedish ball bearing factory, the brand to choose to advanced military things even back then, dam, that says a lot.
Thank you so much ! I'm studying Aeronautical Engineering at the moment (third year already) and I've got to say ... your vlogs are huge support. I get so excited seeing that you are showing a good part of what I'm learning about in school ! Huge thumbs up !
These questions are very important, and the "what if"s reach out to infinity. So I will just tell you there are requirements for each engine, set out by the manufacturer, and we follow those instructions without any attempt to second-guess them. If an owner wants us to violate a requirement of the OEM manual, we will happily ship his partially disassembled engine wherever he wants.
Merry Christmas. Thank-you for your time and energy in posting all these amazing videos. Just can't get enough! Have a wonderful 2013. Cheers from Seattle!
Working on jet engines sounds like a good Christmas to me! I'm stuck writing my graduate thesis, but I always take a break to watch your vids. Thanks for another good one and merry Christmas, Jay!
I love the problem solving aspect of this type of work! I do databases for a living and although I don't work in the same way, we deal with creative problem salving of our own :)
What a great video! I am looking for some video didn't watch, and this one is very nice. I liked that, "mechanical pain". It is correct, use an electric oveb to assembly parts, makes the job easier. Sometimes I used a pan with heated oil, and parts slide so easy. thanks Jay for these great videos.
We don't keep it in the shop, and for us it's a special order from Edmonton... a six hour drive away. Could use dry ice as well. The manual specifies an arbor press. I'm just using thermal expansion here as an alternate method.
This type of work is never done "in the field". This is an engine overhaul shop and we are 5,000Km from this engine's "home". It's good to see you're thinking about safety, though. Thumbs up.
There are more industrial versions of this engine making power on the ground than there are flying ones. Most of the industrial engines have had an OEM upgrade to a larger single bearing.
Using any torch on a bearing is an easy way to destroy it. If you make it change color, it's junk. Also, all of the metals that actually do get hot in operation, like turbine nozzles, blades, seals, and combustor liners do not gain their properties from heat treating. Therefore they can not lose their properties by being heated up.
I never saw this comment before, so I just read it. I don't think you quite read mine right. I was stating that none of the hot section metals or alloys are heat treated. They have their properties in the annealed state. Since they have not been heat treated, they can not lose what they don't have. The continual heating cycles would destroy any heat treatments, so they have none. That's what I was trying to say.
Greetings, I am really enjoying watching your videos .... while watching a few before I was wondering about the bearings... specifically, what bearings that could handle the demands of a jet engine and still allow it to turn by hand looked like... now I know after watching this video. Question: You used heat to very carefully remove the outer housing.... could you use dry ice or liquid nitrogen inside the shaft to shrink the shaft to facilitate an easy removal? Thanks, this is awesome!
If you had ever rebuilt a two stroke dirtbike engine like a YZ250, this is the only way to replace the main ball bearings. You dont even have the luxury of the back of the bearing being open, meaning the bearing is sat into a bowl that is the crank case half, with no hole on the other side. New bearings go in a sealed zip-lock bag and a freezer overnight, then the cast aluminum crank case is heated with a MAP gas torch, to reinstall that new set.
Nice to see that you can just fit 50 year old bearings. Is there no deterioration of the carrier material over time? They do not spin with the full 8000 rpm, but even so there must be pretty high centrifugal forces acting on them. Are this type of bearings regularly tested by the manufacture? I assume that they could advice to fit a newer carrier. Very nice series of videos. A real pleasure to see all the minute details that are so often skipped on Discovery Channel. - Olaf / The Netherlands
Sheet of cardboard under the bearing: Good to have some sort of catch device. I use some variety of this idea all over my shop. Jeff The Alignment Guy ®
Touche. I just took a course about mechanical components/selection in school. It's very nice to see this outside of lectures and text books. Thank you for this video! Another quick question regarding the Iroquois. How the hell did you find it?! It makes me shed a tear every time I think about that beautiful bird we killed. It makes me extremely excited to see its journey to restoration!
would it be easier to put the shaft into dry ice? I suppose not if you already have an oven on hand. ive seen airplane wing bolts fitted by chilling in dry ice to shrink them ever so slightly.
AgentJayZ...are you sure the overhaul cycle on this bearing is 400 hrs? Most engines (and there internal parts) run several thousand hrs between overhaul/replacement cycles. Airliners frequently accumulate 400 hrs in a couple of months time and replacing this bearing would be considered major engine maintenance. Maybe it's 4,000 hrs?
Merry Christmas! Quick question. Why are ball bearings used instead of tapered roller bearings? Or is this just one example of a jet engine using ball bearings...? I know that roller bearings yield a longer service life at higher equivalent radial loads. What's the turbine worlds' explanation? Cheers! Happy holidays
Lol, I have no life either, I took my powerplant cert. Exam xmas eve! Nice gift to myself though! Love the thermal differential installation! I do it a lot too but also utilize the freezer on tighter parts. Is there any industrial Type 14s in use?
Hi Jay, I work at Rolls-Royce at the large fan blade facility in Barnoldswick in the uk, we make all the fan blades for every commercial jet with our engines, I inspect the blades on CMM's the largest being the XWB for the new A350, do you overhaul any of our engines and if so do you inspect the fan blades?
Jay 2 questions for you. 1. Is this going back into a currently flying Saber mk.6 or one under restoration? 2. Have you ever had a pilot of an aircraft who's engine has been overhauled by you ever comment about your videos?
Damn, those are some sexy bearings. What is the fate of the old bearing? If possible, it'd be really cool to make a coaster or something out of one of those.
Haven't thought about purchasing an induction heater instead of using an oven? In saying that, it looks like the oven works just fine. edit: Could the induction heater create uneven hot spots that you'd rather avoid?
Can you please discuss regulatory issues sometime? If a private owner wanted to use that bearing beyond its 400hr rated life, would he be able to? Would the old bearing require specific tests before being returned to service? Would you guys be responsible if the engine subsequently failed? Etc. How do you determine what can and cannot have its service life 'stretched?' The manual + factory service bulletins? Gov't guidelines? Seat-of-the-pants judgement? Or? Thanks for the vids!
1962? is phenolic resin reliable at such an age? I noticed it said SKF. Do they have most of the market? do they make for small engines like WIlliams FJ44 as well? or PW600. And PT6
Packed in preservative grease since whenever means brand new to me. There are several manufacturers of aerospace bearings in the world. I don't know the market share of each. The manufacturer's part number is often different from the engine manufacturer's number. I would expect all turbine engine bearings to be very similar, differing mainly in just their size.
+Greg Ewing There's a lot of work, parts and time between: "It's probably OK to fly those hundreds of passengers over the ocean for another few months" ...and... "We have done everything we can to ensure the safety of you passengers". How much of your life do you want to risk for a discount? (please choose from the following options: 1) All 2) None Thank you! Come again!
Some modern jet engines have had an on wing life of 40000 plus hours. Provided parts that have a ‘life’ aren’t exceeded, engines will normally remain on wing for as long as possible. If the engine during routine inspections proves to be healthy, it will remain on wing. Totally different philosophy for an old military engine like this. This is one of the reasons air travel is affordable to the masses these days unlike 50 years ago.
If the main bearing is the only thing holding the shaft in place axially, wouldn't axial forces on the bearing be tremendous? Related: if the engine is held vertically, isn't the bearing holding the whole weight of the shaft?
+AgentJayZ somewhere between the weight of the shaft and the thrust of the engine. If the shaft wants to move axially, the main bearing's negligible surface area is the only thing stopping it?
I wish you much health and luck. Thank you for you hard efforts you put into the videos. All best wishes to you from germany :) When we will see a turbine powerd motorcycle^^
@agentjayz have they ever made a jet engine with the main thrust bearing at the front or closer to the front for easier serviceability. Or is there a reason it's in the middle ?
Yes, the thrust bearing of some engines is the front bearing. This is not for ease of serviceability ( no such thing with jet engines!), but for design reasons, such as with a large turbofan, making the heavy shaft between the fan and the thrust bearing as short as possible, or even eliminating it.
1. It is very difficult to install an engine in an aircraft that is already flying. 2. If they have, it has been without them identifying themselves to me.
I submit that what you say here reguarding heat treated metals is really half true. heat treated metals are frequently heated and cooled in a very specific way and I submit that careless reheating can in fact change the temperment of the metal :)
Have you ever seen where they immerse a part into liquid nitrogen where the part temperature drops so low that it shrinks and then they drop it into its position. Doing that instead of pressing it into place with a hydraulic press.
+Gilbert Menendez I've done that before in a shop that went to the expense of keeping a stock of liquid nitrogen on hand. Doing that with a bearing instead of heating the outer housing is not advised because after the cold bearing is installed, water in the air condenses onto and into it. Where possible, you could heat it back up with an electric heat gun. Propane or other torches contain a lot of water in their exhaust.
Thats one reason why even fighter jets are replaced sooner or later by new models or are upgraded with new engines... maintenance on military stuff is one of the major costs with these things... I wonder how they wouzld do it during a long war...400hrs is nothing for me.. Whats with newer military engines, how many hours between overhauls ?
Contrary to what you say in the video, the bearing carrier (technical term is cage) has forces exerted on it by the rolling elements, the balls. It is a loaded part and I find it quite strange, that it is made ouf ot plastic, normally bearings this size and meant for high loads have cages made of brass.
to reply to your question, as well as Robert's... it's the thermal difference that we need to use. Sometimes it is easier to chill one part instead of heating the other. Not so in this case. Also, chilling bearings or other parts can cause a lot of condensation of water onto them. This is the reason we would heat a housing, for example, instead of cooling the bearing going into it.
SKF = Svenska Kullager Fabriken (Swedish Ballbearing Factory) Started in my home town in 1907 :-)
Just watched every video on thrust bearings. Loved it. Thanks again 👍🏻
This procedure is performed about 2 times per year in our shop. So the oven is the best multi-purpose heater for our needs.
In Viet Nam, the J79 was routinely replaced in aircraft such as the Phantom II every 200 hours.
Subjected to the stresses of combat, many were replaced at every 100 hours.
Sheesh! It takes thousands of hours to overhaul one...
Our cold chamber is out the door at -25C... but bringing the cold part inside makes water condense on it.
Also, as can be seen in this video, the oven created a sufficient temp difference that cooling the shaft was not necessary.
If we back up just a little bit, and remember this is an engine out of a 60 year old fighter, we might be more inclined to believe the maintenance schedule printed in the engine overhaul manual, where it says replace thrust bearing assembly every 400 hours.
You're free to debate with the OEM manual, but I don't do that.
Turbine engines are commonly described as having a hot section and a cold section, but there is also a "warm" section, which is the shaft and associated machinery that passes through the hot section, but is not exposed to hot gas flow, and is both air and oil cooled.
This is where the thrust bearing lives, and the temps in this area are usually kept below 400F.
...many hundreds of degrees below heat-treating temps.
Tapered rollers are optimized for one direction of axial load, and they are great at very high loads and moderate speeds.
Deep groove ball bearings are better at handling loads in both axial diractions, and are better at moderate loads and high speeds.
I could go on and on, but my comments about bearings always invite great criticism. Which I want to avoid.
6:30 So fun to see the SKF made these military quality ball bearings even all the back in 1962! SKF as we all know is Swedish ball bearing factory, the brand to choose to advanced military things even back then, dam, that says a lot.
Thank you so much ! I'm studying Aeronautical Engineering at the moment (third year already) and I've got to say ... your vlogs are huge support. I get so excited seeing that you are showing a good part of what I'm learning about in school ! Huge thumbs up !
These questions are very important, and the "what if"s reach out to infinity.
So I will just tell you there are requirements for each engine, set out by the manufacturer, and we follow those instructions without any attempt to second-guess them.
If an owner wants us to violate a requirement of the OEM manual, we will happily ship his partially disassembled engine wherever he wants.
My second favorite quote,” aerospace bearings are fun to play with”!!!!
merry christmas/happy holidays to ALL, and, jay, your vids are a present that keeps on giving!! thanks
I'm new to your channel, but I gotta say, it's amazing how much you know about all these critical and complex engines! Congrats man, awesome videos!!
Merry Christmas. Thank-you for your time and energy in posting all these amazing videos. Just can't get enough! Have a wonderful 2013. Cheers from Seattle!
Merry Christmas, Jay. You answered my questions about engine heat while I was typing it. Well played...
Working on jet engines sounds like a good Christmas to me! I'm stuck writing my graduate thesis, but I always take a break to watch your vids. Thanks for another good one and merry Christmas, Jay!
If you we're around doing these vids when I was young, I would have gone into your line of work. Well presented Sir!
If you tube were in my younger years.. ..im sure your vids would've strongly influenced me into the aerospace industry. ..cool vid....
Why I have missed this amazing video for these years
Ah, the tingling of anticipation every time the agent uploads a new video! Keep up the good work, sir!
I love the problem solving aspect of this type of work! I do databases for a living and although I don't work in the same way, we deal with creative problem salving of our own :)
What a great video! I am looking for some video didn't watch, and this one is very nice. I liked that, "mechanical pain". It is correct, use an electric oveb to assembly parts, makes the job easier. Sometimes I used a pan with heated oil, and parts slide so easy. thanks Jay for these great videos.
Thank you AgentJayZ for sharing these videos and Merry Christmas:
I've learned more from your videos than from university courses
Amazing work Z! Such attention to detail and fine craftsmanship from S&S. You have an amazing life, you work on freaking JET ENGINES :)
Excellent engineering practice Jay, Merry Christmas to you.
Man, YOU ARE HELL OF A GENIUS
love you, your channel, your way of putting every thing together
We don't keep it in the shop, and for us it's a special order from Edmonton... a six hour drive away.
Could use dry ice as well.
The manual specifies an arbor press. I'm just using thermal expansion here as an alternate method.
9:09 ''...certain that youre certain..."
very profound
This type of work is never done "in the field". This is an engine overhaul shop and we are 5,000Km from this engine's "home". It's good to see you're thinking about safety, though. Thumbs up.
There are more industrial versions of this engine making power on the ground than there are flying ones.
Most of the industrial engines have had an OEM upgrade to a larger single bearing.
I really enjoy these videos.
Using any torch on a bearing is an easy way to destroy it. If you make it change color, it's junk.
Also, all of the metals that actually do get hot in operation, like turbine nozzles, blades, seals, and combustor liners do not gain their properties from heat treating. Therefore they can not lose their properties by being heated up.
They are scrap, but sought after by people who are fascinated by shiny things...
Agent, you are good. Very very good indeed.
I never saw this comment before, so I just read it. I don't think you quite read mine right.
I was stating that none of the hot section metals or alloys are heat treated. They have their properties in the annealed state. Since they have not been heat treated, they can not lose what they don't have.
The continual heating cycles would destroy any heat treatments, so they have none.
That's what I was trying to say.
Just another piece of equipment taking up space. The oven takes more time... but we're in no hurry!
Going back and catching up is fun.
AgentJayZ no buy. Trade. Cool stuff. Like say before, thrust bearings very hard to get.
Greetings,
I am really enjoying watching your videos .... while watching a few before I was wondering about the bearings... specifically, what bearings that could handle the demands of a jet engine and still allow it to turn by hand looked like... now I know after watching this video. Question: You used heat to very carefully remove the outer housing.... could you use dry ice or liquid nitrogen inside the shaft to shrink the shaft to facilitate an easy removal? Thanks, this is awesome!
lol he said it keeps the balls happy
Merry Christmas AgentJayZ! Love the Vids!
If you had ever rebuilt a two stroke dirtbike engine like a YZ250, this is the only way to replace the main ball bearings. You dont even have the luxury of the back of the bearing being open, meaning the bearing is sat into a bowl that is the crank case half, with no hole on the other side. New bearings go in a sealed zip-lock bag and a freezer overnight, then the cast aluminum crank case is heated with a MAP gas torch, to reinstall that new set.
"Aerospace bearings are a lot of fun to play with."
I'm glad I'm not the only one who plays with bearings.
Nice to see that you can just fit 50 year old bearings.
Is there no deterioration of the carrier material over time?
They do not spin with the full 8000 rpm, but even so there must be pretty high centrifugal forces acting on them.
Are this type of bearings regularly tested by the manufacture?
I assume that they could advice to fit a newer carrier.
Very nice series of videos. A real pleasure to see all the minute details that are so often skipped on Discovery Channel.
- Olaf / The Netherlands
Merry Xmas Mr. Agent, nice trick :)
Sheet of cardboard under the bearing: Good to have some sort of catch device. I use some variety of this idea all over my shop.
Jeff
The Alignment Guy ®
12:35 I think the more impressive figure is what is the load that it supports at 8000 rpm?
Touche. I just took a course about mechanical components/selection in school. It's very nice to see this outside of lectures and text books. Thank you for this video!
Another quick question regarding the Iroquois. How the hell did you find it?! It makes me shed a tear every time I think about that beautiful bird we killed. It makes me extremely excited to see its journey to restoration!
would it be easier to put the shaft into dry ice? I suppose not if you already have an oven on hand. ive seen airplane wing bolts fitted by chilling in dry ice to shrink them ever so slightly.
AgentJayZ...are you sure the overhaul cycle on this bearing is 400 hrs? Most engines (and there internal parts) run several thousand hrs between overhaul/replacement cycles. Airliners frequently accumulate 400 hrs in a couple of months time and replacing this bearing would be considered major engine maintenance. Maybe it's 4,000 hrs?
Merry Christmas! Quick question. Why are ball bearings used instead of tapered roller bearings? Or is this just one example of a jet engine using ball bearings...? I know that roller bearings yield a longer service life at higher equivalent radial loads. What's the turbine worlds' explanation?
Cheers! Happy holidays
Lol, I have no life either, I took my powerplant cert. Exam xmas eve! Nice gift to myself though! Love the thermal differential installation! I do it a lot too but also utilize the freezer on tighter parts. Is there any industrial Type 14s in use?
love it (haven't even watched it yet)
Thank you sir you are doing great job
Sir,
What is the normal working temp of the bearings in service?
Merry Christmas and thanks for this Outstanding channel.
Hi Jay, I work at Rolls-Royce at the large fan blade facility in Barnoldswick in the uk, we make all the fan blades for every commercial jet with our engines, I inspect the blades on CMM's the largest being the XWB for the new A350, do you overhaul any of our engines and if so do you inspect the fan blades?
Working Christmas Eve?
YOU'RE FIRED!
Oh, wait, you own the company. Oh well.
Go relax and take a full day off today!
Hey AgentJayZ Happy Christmas from Clive in the UK
Jay 2 questions for you. 1. Is this going back into a currently flying Saber mk.6 or one under restoration? 2. Have you ever had a pilot of an aircraft who's engine has been overhauled by you ever comment about your videos?
Damn, those are some sexy bearings. What is the fate of the old bearing? If possible, it'd be really cool to make a coaster or something out of one of those.
Haven't thought about purchasing an induction heater instead of using an oven? In saying that, it looks like the oven works just fine.
edit: Could the induction heater create uneven hot spots that you'd rather avoid?
Didn't know that SKF (Svenska kullagerfabriken- "Swedish ball bearing factory") had a plant in Canada in the sixties? Does it still exist?
Merry Christmas
That's OK JayZ, I was up till 2 this morning making the last of my xmas gifts. Steve .G
That was very clever good sir!
With the heat you applied, do you think it's possible to disrupt a quenched and tempered heat treat?
No. Assembly /disassembly heat is about 250 - 350 degrees F. Far too low to affect heat treatings.
Can you please discuss regulatory issues sometime?
If a private owner wanted to use that bearing beyond its 400hr rated life, would he be able to? Would the old bearing require specific tests before being returned to service? Would you guys be responsible if the engine subsequently failed? Etc.
How do you determine what can and cannot have its service life 'stretched?' The manual + factory service bulletins? Gov't guidelines? Seat-of-the-pants judgement? Or?
Thanks for the vids!
so smooth....is the max rpm on that 8k?
Did you put the assembly in the freezer first ?
Thanks Jay.
1962? is phenolic resin reliable at such an age? I noticed it said SKF. Do they have most of the market? do they make for small engines like WIlliams FJ44 as well? or PW600. And PT6
Packed in preservative grease since whenever means brand new to me. There are several manufacturers of aerospace bearings in the world. I don't know the market share of each. The manufacturer's part number is often different from the engine manufacturer's number.
I would expect all turbine engine bearings to be very similar, differing mainly in just their size.
Hopefully about 250F, but they can get up to 400F or more...
A 400 hour service life? Is that an aviation requirement or does that apply to the industrial version as well?
It is the overhaul interval for this engine type only, used in the Canadair Sabre jet fighter.
Every engine type has its own specifications.
Mmmm, SKF.... only the best!
I live a stones throw from their test facility... I used to work there. Indeed Only the best!!
400Hrs! That's all? sheesh. No wonder it is so expensive to operate turbine aircraft/craft/whatever.
+Greg Ewing There's a lot of work, parts and time between:
"It's probably OK to fly those hundreds of passengers over the ocean for another few months"
...and...
"We have done everything we can to ensure the safety of you passengers".
How much of your life do you want to risk for a discount? (please choose from the following options: 1) All 2) None
Thank you!
Come again!
+AgentJayZ I would have still assumed longer than that between replacements.
Different components have different service lifetimes.
Newer engines have longer inspection and overhaul intervals.
Some modern jet engines have had an on wing life of 40000 plus hours. Provided parts that have a ‘life’ aren’t exceeded, engines will normally remain on wing for as long as possible. If the engine during routine inspections proves to be healthy, it will remain on wing. Totally different philosophy for an old military engine like this.
This is one of the reasons air travel is affordable to the masses these days unlike 50 years ago.
Any idea of what the residual value is of a thrust bearing like that after it's hit its 400 hours?
You are a genius
Not really. I just like well made machines. Got that from my uncle Jack.
If the main bearing is the only thing holding the shaft in place axially, wouldn't axial forces on the bearing be tremendous? Related: if the engine is held vertically, isn't the bearing holding the whole weight of the shaft?
+Isaac Lubow what's the definition of tremendous?
The roller bearings at the ends of the shaft also hold up the shaft.
They handle radial loads only.
+AgentJayZ somewhere between the weight of the shaft and the thrust of the engine. If the shaft wants to move axially, the main bearing's negligible surface area is the only thing stopping it?
I wish you much health and luck. Thank you for you hard efforts you put into the videos.
All best wishes to you from germany :)
When we will see a turbine powerd motorcycle^^
@agentjayz have they ever made a jet engine with the main thrust bearing at the front or closer to the front for easier serviceability. Or is there a reason it's in the middle ?
Yes, the thrust bearing of some engines is the front bearing. This is not for ease of serviceability ( no such thing with jet engines!), but for design reasons, such as with a large turbofan, making the heavy shaft between the fan and the thrust bearing as short as possible, or even eliminating it.
AgentJayZ thanks for the reply 👍🏼
1. It is very difficult to install an engine in an aircraft that is already flying.
2. If they have, it has been without them identifying themselves to me.
I submit that what you say here reguarding heat treated metals is really half true. heat treated metals are frequently heated and cooled in a very specific way and I submit that careless reheating can in fact change the temperment of the metal :)
1962，its amazing .
Have you ever seen where they immerse a part into liquid nitrogen where the part temperature drops so low that it shrinks and then they drop it into its position. Doing that instead of pressing it into place with a hydraulic press.
+Gilbert Menendez I've done that before in a shop that went to the expense of keeping a stock of liquid nitrogen on hand. Doing that with a bearing instead of heating the outer housing is not advised because after the cold bearing is installed, water in the air condenses onto and into it. Where possible, you could heat it back up with an electric heat gun. Propane or other torches contain a lot of water in their exhaust.
8000 rpm with hell of a load, talk about quality.
Those out of a Orenda type 14?
Thats one reason why even fighter jets are replaced sooner or later by new models or are upgraded with new engines... maintenance on military stuff is one of the major costs with these things... I wonder how they wouzld do it during a long war...400hrs is nothing for me..
Whats with newer military engines, how many hours between overhauls ?
We never see any civil aviation engines. Industrial, military and experimental only.
where are you located in canada..May I visit your service centre "once"
Contrary to what you say in the video, the bearing carrier (technical term is cage) has forces exerted on it by the rolling elements, the balls. It is a loaded part and I find it quite strange, that it is made ouf ot plastic, normally bearings this size and meant for high loads have cages made of brass.
www.skf.com/us/products/bearings-units-housings/roller-bearings/principles/bearing-data-general/materials-for-rolling-bearings/cage-materials/index.html
If it did more than provide spacing for the balls I'm sure it would be destroyed in seconds once running
cant u just cool the centre tube with dry ice?
The cold parts cause condensation, which can cause corrosion.
At 4.03 if it was not a split inner race it would not be possible to pack as many balls as this bearing contains.
nice !
As a pilot... I like you, we can be friends.
happy late christmas :D
Like magic! :D
👍
शायद हैलीकॉप्टर में थ्रस्टर्स बैरिंग इस्तेमाल होते है
Merry xxxmas