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T.Hoffman
09-30-2010, 09:16 AM
I got all my new bearings in for my older drill press, and wondering about the best way to install them.

Besides pressing in by force, I've read that you can heat the bearing for installing on a shaft, or heating the part for installing the bearing in a bore.

Good idea? What temp should I be considering so that the bearing and/or grease isn't damaged?

A.K. Boomer
09-30-2010, 09:50 AM
Before heating you need to verify there are no seals and or nylon cages and such,

Depends on the application but I rarely heat bearings and many times don't even use a press, The trick is not loading the bearing running surfaces themselves while either pressing or tapping them in,


most times I tap bearings into their boss, a small ball peen hammer and a brass drift does the trick - if its a shaft then use the brass drift on the inner race - if its a bore then use it on the outer, I alternate 180 degrees apart or sometimes 120 depending how tight the bearing.

Concerned about galling? use some anti-seize compound on both surfaces...

T.Hoffman
09-30-2010, 10:06 AM
Double sheilded bearings.

They are pressfit in the bore and on the shaft at the same time... I was thinking about heating the outer housing in the oven and freezing the shaft for installation all at once.

polepenhollow
09-30-2010, 10:09 AM
I usually make an arbor for pressing bearings.
Arbors are usually made on a lathe from Al, but I have even made them of wood.
Pilot and OD of arbor are usually .005 to .010 undersize.
Clear away material from the arbor so the non loaded dia of the bearing is not pressed.
If you are installing a bearing so the OD is the press, clear around the inner race so it is not loaded during the assembly. Vice versa applies also.
Use grease or anti-sieze.
Worst case use a socket to install bearing.
Inspect the bore of the hole before pressing. Make sure there are no slivers on the edge of the bore. I use a small round stone to make sure the bearing is going into a clean chamfer on the bore.
Inspect the chamfer on the bearing also for similiar condition.
Check for the thrust faces on the bearing before assembly. Make sure bearings are installed in the proper realtionship to thrust loads.
(Ball thrust bearings)
K Lively

paulx
09-30-2010, 10:20 AM
I use a 200 f degree temperature indicating crayon.Others I`ve worked with wet their fingertips with water to test.When the bearing sizzles to the touch it is ready.Wear gloves.Need to carefully line it up and slide the bearing on quick or it will shrink before seated.

lazlo
09-30-2010, 10:53 AM
Ditto the other posts: I use 200°F. The Old Timer's trick was to put the bearing on a light bulb -- that's pretty close to the right temperature.

One thing to note: hold the bearing in place until it cools down. Ask me how I learned that lesson :p

A.K. Boomer
09-30-2010, 11:04 AM
Double sheilded bearings.




So how can you see the cage material?

Spin Doctor
09-30-2010, 11:08 AM
One point. Never, ever use brass on bearings. brass is much more likely to chip than other materials. If a punch must be used, the best material is either a plastic sleeve that is sized to the outer and inner diameters (especially if you are going into a bore and the shaft at the same time) or is it is on just one a mild steel sleeve or punch. The reason you will hear that you should not use steel punches on bearings is because people will grab a hardened punch and that you never want to do

Boucher
09-30-2010, 11:21 AM
I got started using an old electric iron to degrade locktite and epoxy when taking barrels and glued in actions apart on guns that I was working on. You use the linen setting and set the iron on the action wrench and leave it for a while. That led to using the Iron to heat bearings and the IR thermometer to monitor the temperature.

A.K. Boomer
09-30-2010, 11:22 AM
Totally disagree Spin, brass drifts are just fine - and in fact its one of the main reasons they build them,
all material will chip if not maintained - even lead, It just common sense that you want a nice little chamfer on both the hammer end AND the driving end of the drift and you will avoid chipping --- that goes for any drift - hardened metal - soft metal - brass - aluminum or even copper.

Brass transmits shock loads very well without having the ability to bumfuque the surface.
It's for this reason that brass is ideal for situations like bearing installations.

Mcgyver
09-30-2010, 11:30 AM
One point. Never, ever use brass on bearings. brass is much more likely to chip than other materials. If a punch must be used, the best material is either a plastic sleeve that is sized to the outer and inner diameters (especially if you are going into a bore and the shaft at the same time) or is it is on just one a mild steel sleeve or punch. The reason you will hear that you should not use steel punches on bearings is because people will grab a hardened punch and that you never want to do

SD, I always operate on the principle that you're fine so long as you're not loading the roller elements; ie make a sleeve out of pipe or such to fit the inner race when pressing on a shaft......but how to do you install something that that's a press on both bore and shaft as OP says is the situation here? just assume the races are the same height or that there's enough play and use a flat faced tool against both? thanks

Boucher
09-30-2010, 11:35 AM
I have used 1/2" drive sockets for a bushings to push on the bearing or the race for pushing it into position. They often fit. When they don’t I make a bushing from 7075-T6 which is surprisingly tough and works good in this application. I got started using 7075 when I lucked into some cheap at the salvage place. It worked so well that I now stock it in several convenient sizes.

T.Hoffman
09-30-2010, 11:41 AM
I looked up the manufacturer specs, and they do mention heating the bearings as an installation option, but not above 170* F.

There is a plastic spacer that goes between the two bearings on the shaft, so I'm hesitant to start using great pressure to install them on the shaft or in the bore without distorting that plastic spacer.

Is freezing the bearings harmful in any way? I wouldn't think so, but just asking.... I was thinking I could install the bearings on the shaft first by freezing the shaft and slightly warming the bearings. Then, freeze the entire shaft with bearings installed, and heat the outer bore housing for final installation. Sound like a plan?

Stepside
09-30-2010, 12:09 PM
It is my understanding that either the inner race or the outer race should be a tight slip fit to allow for shaft length changes due to temperature. The load on the bearing is controlled by spring washers or other methods to keep load constant as the shaft gets warmer or cooler. Am I making a mountain out of a molehill or is it an issue?

J. R. Williams
09-30-2010, 12:13 PM
I use an old electric clothes iron to heat a bearing at installation. I hold the iron in my vise with the plate level and add a couple drops of lube oil to the surface the improve contact with the iron. I heat the bearing to about 150 deg F and it will slide on to the shaft very easy.

JRW

Spin Doctor
09-30-2010, 01:27 PM
Back in my old job when I was rebuilding spindles this is what we used for shaft and bore fits at the same time.

http://www.skf.com/files/267023.pdf

Evan
09-30-2010, 01:31 PM
Then, freeze the entire shaft with bearings installed, and heat the outer bore housing for final installation. Sound like a plan?

Don't freeze steel bearings for installation. At most you may cool them in the refrigerator. Bearing steels have a high ductile/brittle transistion temperature that may be only a small amount below the freezing point of water. Below that temperature they are very sensitive to shock loads and may crack if subject to impact. It is one of the reasons that rail cars used in cold climates still use plane bearings in most cases instead of roller bearings.

leesr
09-30-2010, 01:36 PM
a cheap way is to buy very small chunks of dry ice in a cheap foam chest.
never use dry ice in a sealed container due to explosion.

place & cover the shaft in the dry ice for 30 min. use an IR temp gage to monitor the temp. dry ice is at -120 deg F
use protective gloves to prevent freeze burns.

what is the outer housing made from ? steel
heat to 275 deg F & soak 1 hour per inch thickness.

make fixturing from soft tooling, aluminum, brass etc
ditto on every one else's comment about where to locate from.

thermal assembly must be done fast or it will seize. then must use press force.

leesr
09-30-2010, 01:43 PM
Just wanted some opinions.

Is it OK to press bearings with out thermal treatment (freeze & heat)

press bearings in a press only

your thoughts gentlemen.

paulx
09-30-2010, 02:03 PM
Just wanted some opinions.

Is it OK to press bearings with out thermal treatment (freeze & heat)

press bearings in a press only

your thoughts gentlemen.

I think its ok.Heating & freezing is easier for large bearings .Small bearings can be pressed or even knocked on with a hammer.The main thing is not to transmit force thru the balls(rolling element).

leesr
09-30-2010, 02:16 PM
Paulx

thanks for the reply.
I would like to hear more comments.

Thank You

Leesr

Mcgyver
09-30-2010, 02:18 PM
. Below that temperature they are very sensitive to shock loads and may crack if subject to impact. It is one of the reasons that rail cars used in cold climates still use plane bearings in most cases instead of roller bearings.

what about all the cars on the road?

Evan
09-30-2010, 02:42 PM
They have rubber tires.

MuellerNick
09-30-2010, 03:15 PM
Generally, bearings can stand temperatures up to 120 °C (at least during mounting). Special bearings go up to 300 °C (addendum S0 .. S3).
The lower working temperature is -30 °C to -20 °C, but more because of the cage and lubrication. I'm not aware of anyone having shattered a bearing because of freezing it (even in dry ice).

If you do have a temperature difference of 100 °C, mounting should work smooth in most cases. But time is critical!

I have heard not to use brass several times. Even from people that do have some clue about bearings.


Nick

Evan
09-30-2010, 03:20 PM
Freezing a bearing doesn't shatter it. Pounding on it while frozen will.

The Fixer
09-30-2010, 03:28 PM
I use a hot oil bath to heat bearings for installation on a shaft, this works better than the frying pan etc. as it provides a more even and consistent temp control. Also there is less likelihood of overheating the brg as well. I've seen guys heating bearings with everything from a torch to a toaster! lol In the bush we'd get a metal 5 gal pail, some hydraulic oil, and a tiger torch for a field fix.
Edit: The torch and electric stove element is a good way to take the temper out of the bearing as well, if it gets hot enuf to change the surface color you've changed the temper of the bearing.
al

MuellerNick
09-30-2010, 03:29 PM
Pounding on it while frozen will.

I prefer pressing them in.


Nick

Black_Moons
09-30-2010, 03:49 PM
It is one of the reasons that rail cars used in cold climates still use plane bearings in most cases instead of roller bearings.

Wow, thats just amazing to think of trains running on plane bearings.. All that weight. Wonder what size those bearings must be..

T.Hoffman
09-30-2010, 04:17 PM
Freezing a bearing doesn't shatter it. Pounding on it while frozen will.

If you freeze the bearing and heat the housing, will any (or much at all) pressure be needed to get them in?

leesr
09-30-2010, 04:50 PM
normally it will fall in. if the heat temperture is high enough &
if the freeze temp is low enough.

it depends on what the heating temperature-room temperature (70deg F) x the the coefficient of thermal expansion(find it in the machinery handbook)
then x the size of the diameter= the expansiom amount.

linear expansion per unit length per deg F steel= .00000633"

leesr
09-30-2010, 04:53 PM
OK poll
is it advisable to press bearings at room temperture.

no thermal expansion.

:eek:

Evan
09-30-2010, 07:10 PM
Wow, thats just amazing to think of trains running on plane bearings.. All that weight. Wonder what size those bearings must be..


Plane bearings are the weight handling king of the bearing world. They are used for the really heavy applications such as truly large cranes, propellor shafts on ships and very large machinery like draw bridges and similar.

As for the ductile/brittle transition effect in steels it isn't just limited to high strength steels although they tend to have the highest transition temperatures.




Background
History: Why would a steel that is normally capable
of sustaining great loads and capable of ductilities
greater than 20 percent suddenly, when cold, become
so brittle that it could be shattered by a minor blow
or similar impact? This was the question asked over
a hundred years ago when fractures occurred in steel
structures in severe weather. Since then many similar failures have been documented. There a
number of possible reasons for such failures: fatigue, corrosion, fabrication and design errors, poor
quality steel, etc. The most dramatic and unexpected cause of brittle failure in ferrous alloys is their
tendency to loose almost all of their toughness when the temperature drops below their ductile to
brittle transition temperature. This has been the cause for numerous dramatic and catastrophic
failures, i.e. the rupture of a 2.3 million gallon molasses storage tank in the winter of 1911, bridge
failures, liberty ships breaking in half in the harbor and at sea during World War II and other
disasters (see ASTM STP 158, and the figures and text following the references). The earliest
record of such failures dates back to 1879. This was when good, cheap Bessemer and open hearth
steels had just begun to become widely used. (The Bessemer process was introduced in 1860. Prior
to that, steel had been made by an expensive process of carburizing wrought iron. The expense
limited the uses of steel to special applications.) The problem of brittle failure of steel structures
was severe during and just after World War II. Between 1942 and 1952 around 250 large welded
steel ships were lost due to catastrophic brittle failure. Another 1200 welded ships suffered
relatively minor damage (cracks less than 10 feet long) while over 1900 riveted ship have broken
in two or lost at sea. Over 58 cases of non-ship failures had been reported. Many of these may have
failed by non-brittle processes while many failures probably have gone unreported due to adverse
publicity it would generate [3].

http://www.kstreetstudio.com/science/experiments/files/DuctileBrittleTransition.pdf

Mcgyver
09-30-2010, 08:15 PM
Wow, thats just amazing to think of trains running on plane bearings.. All that weight. Wonder what size those bearings must be..

Its slow (hundreds not 1000's of rpm) and heavy..like a bulldozer vs lady in high heels, psi is less for the bulldozer. Given the small area of contact with roller bearings that's what i would have guess was the why, not that the steel wouldn't stand the shock....but apparently they've got steel now that can perform in sweater weather, I haven't had a truck apart recently but it seems roller element bearings are common in rail.

http://www.timken.com/en-us/solutions/rail/Documents/Trackside%20Inspection.pdf

http://www.skf.com/portal/skf/home/products?maincatalogue=1&lang=en&newlink=1_21_9

lakeside53
09-30-2010, 10:09 PM
OK poll
is it advisable to press bearings at room temperture.

no thermal expansion.

:eek:


It depends on the fit of the shaft and outer casing. In my experience, most drill press issues are fine at room temperature, but do use a simple mandrel and use an arbor style press (so you can feel). Make sure everything is square and that you support the item receiving the bearing in the same way.

I have installed literally thousands of bearings into steel and aluminum/mag cases. With aluminum and mag, I heat the cases to 225-250F in a convection oven for 20-30 minutes minutes - the bearing is simply placed into the case by hand - a lot of room to spare. Same temperature with steel, but some press pressure is required.

Hot oil is an excellent way to place bearings (steel cages) on a shaft. I heat the the oil and bearing to 250F, cool the shaft over night in the freezer - the bearing just drops on or slides with small pressure.

gearedloco
10-01-2010, 01:51 AM
Its slow (hundreds not 1000's of rpm) and heavy..like a bulldozer vs lady in high heels, psi is less for the bulldozer. Given the small area of contact with roller bearings that's what i would have guess was the why, not that the steel wouldn't stand the shock....but apparently they've got steel now that can perform in sweater weather, I haven't had a truck apart recently but it seems roller element bearings are common in rail.

http://www.timken.com/en-us/solutions/rail/Documents/Trackside%20Inspection.pdf

http://www.skf.com/portal/skf/home/products?maincatalogue=1&lang=en&newlink=1_21_9

Roller bearings are now required on rail cars used in interchange service, IIRC. For the first hundred years or so of railroading, friction bearings were
used just about exclusively. I believe roller bearings started to be used widely after WWII.

The "journal" , which is actually the end of the axle, was finished and polished to a fairly high degree. The bearing or "brass," which rode on the journal, was usually made out of some brass alloy. The bottom part of the journal box contained a wad of cotton waste, which was soaked in a fairly heavy oil. The top of the wad rubbed against the bottom of the journal, which wicked oil up to lubricate the bearing.

On occasion, a strand or three of the waste would stick to the journal and be pulled between the journal and the brass. This didn't do the surfaces any good, and the resulting friction would often set fire to the cotton waste and oil.:eek: This was known as a "hot box."

If the folk in the caboose were doing their job and watching the train, one or more would notice the problem, and usually partially apply the train brakes by venting the train brake air line, to get the attention of the engineer who would then stop the train.

The crew would attempt to extinguish the fire and inspect the journal. The usual result was to proceed slowly to the next spur, where the offending car would be set out of the train.

After the problem was reported at the next station or crew-change point, a crew of 3 or 4 carmen would be sent out to repair the problem. This was done by dragging a _HEAVY_ jack to the offending journal box, jacking the weight off of the "brass" (bearing) and replacing it with a new brass. The journal would be inspected, the cotton waste replaced and oiled, and the jack removed.

A later train would be assigned to pick up the car and take it to the next repair yard.

If there were signs of damage to the steel journal, a "slow order" would be placed on the train moving the car, and at the repair yard the wheel-set (axle and 2 wheels) would be replaced with a serviceable unit, the "brasses" replaced, and the journal packing would be replaced and oiled. Then the car would be sent on it's way.

On occasion, the journal bearings would fail catastrophically. But I've babbled on way to long to go there!:rolleyes:

And that is why roller journal bearings took over on the railroads rather rapidly after they were developed and proven.

A visit to your local rail museum would probably make the above a bit more understandable, if you are really interested.

-bill

Evan
10-01-2010, 04:57 AM
Its slow (hundreds not 1000's of rpm) and heavy..like a bulldozer vs lady in high heels, psi is less for the bulldozer.

Crankshaft bearings are plane (plain) bearings. So are most turboshaft engine bearings. Plane bearings are still widely used in railcar service in cold climates.

MuellerNick
10-01-2010, 05:46 AM
Crankshaft bearings are plane (plain) bearings.

They do have pressure lubrication (hydrostatic). Ever seen an oil pump at a railway car?


Nick

Spin Doctor
10-01-2010, 06:39 AM
Totally disagree Spin, brass drifts are just fine - and in fact its one of the main reasons they build them,
all material will chip if not maintained - even lead, It just common sense that you want a nice little chamfer on both the hammer end AND the driving end of the drift and you will avoid chipping --- that goes for any drift - hardened metal - soft metal - brass - aluminum or even copper.

Brass transmits shock loads very well without having the ability to bumfuque the surface.
It's for this reason that brass is ideal for situations like bearing installations.

If that's the case then why do bearing manufactures specifically say to avoid using brass along with spindle manufactures who's schools I've been to.

Evan
10-01-2010, 08:35 AM
They do have pressure lubrication (hydrostatic). Ever seen an oil pump at a railway car?


No. There isn't one on my South Bend either. Hydrodynamic bearings will work without pressure oil even a fairly high rpms. It even works in millions of small engines at reasonably high rpms with no oil pump and crap for bearing materials.

That however isn't the point. The point is simply that it isn't a good idea to freeze a hardened steel bearing and then drift it into place. It may crack. If you doubt me then try freezing a bearing outer race and see how easily it breaks.

gary350
10-01-2010, 08:48 AM
NEVER hit the bearing with a hammer to install it.

I never use heat either. Heat will last only long enough to get the bearing started then the heat transfers to the cold part and the bearing gets stuck. Put some grease on both parts and press them together.

A.K. Boomer
10-01-2010, 08:49 AM
" If that's the case then why do bearing manufactures specifically say to avoid using brass along with spindle manufactures who's schools I've been to. "



Guess it depends on the school you go too;)

The one I went to was about 32 years ago and stated exclusively to use brass, I been doing it ever since and never had a problem, another good thing about brass is if there are small particulates left behind the ball/rollers and races will not be damaged when they roll over them under load.

Mild steel is fine too although maybe not as forgiving if little pieces are left behind,
Like someone else stated good quality aluminum can work great also and will not harm the running surfaces.

Its not rocket science - you can basically use anything that works as long as its not hardened - ohh yeah - stay away from using exploding bolts, that wouldn't be a good choice either.

The trick to using any drift is to finesse the bearing in place - many guys get the bearing mis-aligned and not only keep hammering in the wrong area but hammering harder, the first 1/3 of insertion is the most critical for cocking -- if the bearing starts to self wedge and your eyes aren't that good to tell which direction its off then stop "tapping" on it and get your calipers and use the end as a depth gauge to find out where you need to hit, The other trick is to use a very small little compact ball peen hammer, if you have a dead blow ball peen that can be very good also,
You take a look at the situation -- bearing size and such and you do not surpass your pre-determined shock load - if it gets stuck then somethings wrong, don't beat on it harder - find out whats going on.

There's always tricks you can do to get the bearing in place without utilizing more and more force, easy press bearing will go in with just using the side to side 180 degree opposed method - harder ones may require a walk around of 120 degree's --- really hard ones require a close knit walk around of 60 degree's or even less...

Brass is just fine to use and when given the options its my drift of choice.
As far as making the statement to "never ever use brass" ------- that's BS...

Ed P
10-01-2010, 09:10 AM
The following is taken from the Barden Bearing Corporation catalog. (The capitals are mine.)
"7. Assemble only clean burr-free parts. Make sure the bearing seats on the shaft and in the housing are clean.
8. For interference fits, use heat assembly (differential expansion) or an abbor press. NEVER USE A HAMMER or a screw driver and NEVER APPLY SHARP BLOWS.
9. Apply force to the ring being press fitted. A tube made of a softer material and with the end faced square to its axis should be used to press against the ring being press-fitted.
Never push the outer ring to force the inner ring onto a shaft, or brinelling could result..."

Ed P

Richard-TX
10-01-2010, 09:17 AM
http://www.ntnamerica.com/industrial_mountings.htm

lazlo
10-01-2010, 09:21 AM
http://www.ntnamerica.com/industrial_mountings.htm

That's a good link Richard. I don't like using a hammer either (I usually use a PVC "drift") but sometimes there's no other way.


Cold Mounting
Interference fits require even more care during installation due to the bearing having a smaller bore or a larger outside diameter than the mating part. Bearings with relatively small interference fits can be press fit at room temperature by using a sleeve against the ring face as shown in figure 1. Bearings are frequently mounted by striking the sleeve with a hammer; however, if available, a mechanical or hydraulic press will apply a more uniform force.

When mounting a non-separable bearing on a shaft and in a housing at the same time, a pad that distributes the fitting pressure evenly over the inner and outer rings should be utilized as shown in figure 2.

Heated Mounting
Bearings with large inner ring interference (and large bore bearings), require a considerable amount of force to mount at room temperature. Mounting in these cases is facilitated by heating and thus expanding the inner ring. The amount of heating required depends on the amount of interference and the shaft diameter.

A commonly used method to heat bearings is to immerse them in hot oil. To avoid overheating, the bearing should be suspended inside the heating tank on a wire grid. Never bring bearings in direct contact with the heating element or bottom of the heating tank.

Another commonly used method to heat bearings, including pre-lubricated sealed and shielded types, is by using a hot plate. Gaps between the inner ring and the abutment are avoided by holding the inner ring against the shaft abutment during cooling.

It is essential to apply heat uniformly throughout the entire bearing. It is recommended that a torch not be used to heat the inner ring during installation due to the very high localized heat torches produce. No matter what method is used: NTN Bearings should never be heated above 120°C (248°F)

lazlo
10-01-2010, 09:30 AM
I never use heat either. Heat will last only long enough to get the bearing started then the heat transfers to the cold part and the bearing gets stuck.

Heat is much gentler to the bearing. The bearing has enough mass that you have about 20 - 30 seconds (depending on the size of the bearing) to get it on. After that, like I alluded earlier, the bearing will grab the shaft wherever it happened to be, in whatever orientation it happened to be.

SKF, Barden, Timken... sell bearing heaters, both hot plate heaters and induction heaters:

http://www.beltco.com.my/catalog/images/SKF/SKF%20BEARING%20HEATER%20TIH%20210M.jpg

ikdor
10-01-2010, 09:32 AM
Bearing steels have a high ductile/brittle transistion temperature that may be only a small amount below the freezing point of water. Below that temperature they are very sensitive to shock loads and may crack if subject to impact. It is one of the reasons that rail cars used in cold climates still use plane bearings in most cases instead of roller bearings.

Judging from this article, rolling bearings are also used on freight trains in arctic climates.
http://evolution.skf.com/zino.aspx?articleID=296&lan=en-gb

With regards to using a hammer to install small bearings, the SKF mounting kit even includes a dead blow hammer....
http://www.mapro.skf.com/images/f_tmft36.jpg

Igor

MuellerNick
10-01-2010, 11:52 AM
There isn't one on my South Bend either.

Maybe a lathe has zero load when the spindle is not running?


Hydrodynamic bearings will work without pressure oil even a fairly high rpms.

Too funny! They even don't work at all at zero RPM or low RPM.


It even works in millions of small engines at reasonably high rpms with no oil pump and crap for bearing materials.

Maybe because the load increases with RPM? Maybe because when there is some load, there is a minimum RPM (called idle)?
Does a train get heavier the faster it goes?


Nick

MuellerNick
10-01-2010, 11:54 AM
With regards to using a hammer to install small bearings, the SKF mounting kit even includes a dead blow hammer....


The rings are out of PA or POM, the hammer is plastics too.


Nick

Evan
10-01-2010, 12:32 PM
Now you have stopped making any sense Nick. Another useless discussion.

leesr
10-01-2010, 01:03 PM
Lazlo

nice post on the bearing heaters.
an other nice option if assembling large qty's.

Evan

always nice info on your post

nice post every one nice brain storming going on
I like seeing the different opinions

have open air furnace at my disposal, so that is what is used here.
liquid nitrogen is what is used here for assembling other than bearings.

what about assembling plain bronze bearings into housings or similar?

nice post every one.

Leesr

T.Hoffman
10-01-2010, 01:23 PM
I don't have a heater plate, wouldn't a normal kitchen oven do just as well?
Set at around 160-170*F with my temp monitor keeping an eye on things?
Might stink a little bit, but that's ok.
Maybe a half-hour or so in the oven to get them to temp?

....."how would you like your bearings done sir?"
"Medium-well please."....

Also, what about localized freeze spray used in electronics to cool things down? That stuff is pretty potent from what I remember.... Obviously the more mass you have, the more spray it would take, but still it might assist with install.

MuellerNick
10-01-2010, 01:56 PM
Now you have stopped making any sense Nick. Another useless discussion.


Ah, Mr. Even tries to simulate the educated!
Maybe you start referencing what exactly you mean with "Now you have stopped making any sense Nick".

You can't argue, you can't explain, you can't give reasons, you can't discuss, you don't know!

Or what exactly didn't you understand about the critical phase of a hydrodynamic bearing?


Nick

tdmidget
10-01-2010, 03:55 PM
Evan could give an example of a railroad using plain bearings? It wouldn't be in North America since cars have to be interchangeable and Plain bearings have not been acceptable in interchange since 1994.

paulx
10-01-2010, 04:25 PM
...or you could use a piece of aluminum plate and heat the underside with a propane torch.

The spray idea sounds expensive.

leesr
10-01-2010, 04:45 PM
I don't have a heater plate, wouldn't a normal kitchen oven do just as well?
Set at around 160-170*F with my temp monitor keeping an eye on things?
Might stink a little bit, but that's ok.
Maybe a half-hour or so in the oven to get them to temp?

....."how would you like your bearings done sir?"
"Medium-well please."....

Also, what about localized freeze spray used in electronics to cool things down? That stuff is pretty potent from what I remember.... Obviously the more mass you have, the more spray it would take, but still it might assist with install.

it made contaminate your oven, smoke from the parts.
otherwise it would work
possible use Propane torch to heat up the housing. use a cheap IR temp gage from Harbor Freight.
use the dry ice it's very cheap.
make some cheap tooling from soft stock on hand.

Evan
10-01-2010, 04:53 PM
Evan could give an example of a railroad using plain bearings? It wouldn't be in North America since cars have to be interchangeable and Plain bearings have not been acceptable in interchange since 1994.

We have a large number of what are called "unit trains". They primarily transport wheat and coal to the Prince Rupert terminal from the coal mines in northern BC and Alberta as well as wheat from the central provinces. They are not interchanged or even uncoupled. They travel through some of the coldest parts of the country with winter temperatures as low as minus 50 and routinely at -30. Since these carriages are never interchanged they are not required to have roller bearings. That is also the case in the US.

Evan
10-01-2010, 04:56 PM
Ah, Mr. Even tries to simulate the educated!
Maybe you start referencing what exactly you mean with "Now you have stopped making any sense Nick".


I see you don't understand. Not surprising.

[ignore=on]

MuellerNick
10-01-2010, 05:05 PM
This is an excerpt from SKF-INA (unfortunately in German):
"Ist ein fester Sitz des Außenrings vorgesehen, so wird das Gehäuse meist angewärmt. Bei sperrigen und großen Gehäusen stößt das mitunter auf Schwierigkeiten; in diesem Fall kühlt man das Wälz- lager mit einer Mischung aus Trockeneis und Alkohol. Dabei sollte die Temperatur von –50 °C nicht unterschritten werden."

Source (http://www.fag-ina.at/explorer/download/waelzlager/MontagevonWlzlager.pdf), chapter 3.2.6

Basically, they suggest to cool down the bearing with a dry ice-alcohol-mixture. They suggest not to go below -50°C.

An other "idiot" suggesting dry ice is NTN: Read this, page A100 (http://www.ntnamerica.com/pdf/2200/brghndlg.pdf).

But fools collect! Read this (http://www.nsk.com/services/maintenancerepairs/mounting.html)

As someone -unwillingly- already said: Useless discussion!


Nick

MuellerNick
10-01-2010, 05:25 PM
Now to the necessary temperature difference:

The "worst fit" you find in bearing fits is a shrink fit.
The tolerance is P6. Clearly a shrink fit!
At 100 mm diameter, the undersize is 15 to 52 µm (for a standard bearing, precision bearings have tighter tolerances at the diameter).

Termal expansion rate of steel is 13 * 10^-6 K^-1. At 100 mm, that makes 1.3 µm/K. 100 °C (or K, if you prefer) difference makes an expansion of 130 µm or 0.13 mm. Nuff for the 0.052 mm I guess.

As I said previously, 100 °C difference are enough.

But I'm only telling nonsense ...
Nick

MuellerNick
10-01-2010, 05:30 PM
I see you don't understand. Not surprising.

I see, you are one of that kind who picks the lamest excuse he could find to retract when he was driven into a corner and can't stand to have to admit that he told nonsense.

Thanks for ignoring me, one **** less to discuss with.:D

Nick

MuellerNick
10-01-2010, 05:59 PM
And now for the temperature range:
As I said earlier, standard bearings (they do come greased) start at -20 °C (some at -30°C). The reason is the cage, but more the grease. Contact the manufacturer!

Here, you can read it: Linky (http://www.mt-online.com/lmt-rokstories-places-holder/246-julyaugust2009/1321-the-lowdown-on-lubricants-for-rolling-bearings.html) Chapter operating temperature. But you can get aviation grade grease that works below -70 °C


But I'm too stupid to understand ...
Nick

lazlo
10-01-2010, 06:15 PM
I don't have a heater plate, wouldn't a normal kitchen oven do just as well?
Set at around 160-170*F with my temp monitor keeping an eye on things?


That would probably be fine -- I've used the 100 Watt lightbulb trick before, and it works just as well.

I have an industrial hot plate in my shop, and I use one of those cheap Chinese infrared thermometers to set a reading of 200°F on the bearing race on it. Another option would be the Tempil temperature crayons which you can get at any welding supply, but they're $8, and I think the infra red thermometer runs $20 at Sears or Harbor Freight...

MuellerNick
10-01-2010, 06:21 PM
"The needed bearing lifetime also varies with the application. For example, Tedric A. Harris reports in his Rolling Bearing Analysis[3] on an oxygen pump bearing in the U.S. Space Shuttle which could not be adequately isolated from the liquid oxygen being pumped. All lubricants reacted with the oxygen, leading to fires and other failures. The solution was to lubricate the bearing with the oxygen. Although liquid oxygen is a poor lubricant, it was adequate, since the service life of the pump was just a few hours."

Source (http://en.wikipedia.org/wiki/Rolling-element_bearing)

As a reminder, oxygen's boiling point is at -182.95 °C

And the Space Shuttle has NO rubber tires (well, just for landing), so that doesn't count for an excuse. :D



Nick

Evan
10-01-2010, 07:40 PM
You are amusing when you become desperate Nick. You neglected to mention just what sort of bearings that SKF technical document is referring to.

http://ixian.ca/pics7/nick1.jpg

I do read German just fine. They don't just "suggest" that you not cool it below -50. They post it in large red letters beside the paragraph you quoted.

http://ixian.ca/pics7/nick2.jpg

You accidentally failed to mention that they strongly recommend that the bearings be pressed on, not hammered. If they must be "hammered" then it should be with a very light hammer used to tap the bearing in place.

A bearing in those sizes doesn't cool or warm very quickly and the expansion and contraction is proportionately much greater than when dealing with the sizes used in a home shop.

Also, the ductile to brittle transition for standard 52100 bearing steel doesn't happen suddenly between -50 and -51. It starts at a much higher temperature and it also depends on the alloys. Stainless steel bearings are not a problem in that respect but they are very expensive. It's the sort of thing that NASA would use.

Here is a representative chart of the ductile/ brittle transition temperatures (dbtt) for various steels. Note that as the carbon content goes up the brittleness goes up so the curve is flattened. As well, the DBTT rises. 52100 steel is 1% carbon steel with a low amount of chromium added. It begins to grow more brittle at around zero celsius.

http://ixian.ca/pics7/nick3.jpg
http://www.feine-klingen.de/PDFs/verhoeven.pdf

If you pay attention Nick you might just learn something.


But, I doubt it.
click! clickety-click! Damn, the ignore button seems to be intermittent.

MuellerNick
10-02-2010, 04:13 AM
You accidentally failed to mention that they strongly recommend that the bearings be pressed on, not hammered. If they must be "hammered" then it should be with a very light hammer used to tap the bearing in place.

You willingly failed to read posting #59. And who was talking about a sledge hammer?


A bearing in those sizes doesn't cool or warm very quickly and the expansion and contraction is proportionately much greater than when dealing with the sizes used in a home shop.

OH MY GOOD! How brainless is this argument?
If it cools slow, take more time. Thermal expansion rate is not size dependent, it only depends on the temperature difference.


They don't just "suggest" that you not cool it below -50. They post it in large red letters beside the paragraph you quoted.

Maybe you read the text. They say "sollte nicht" (= avoid to). This is not imperative. It would read "darf nicht" (shall not) as you translated.
Anyhow, did you read the other links, where that limit is missing? Did you read the quote from the Space Shuttle? Or were you once more too selective in your reading? And didn't you tell that it gets brittle a 0°C?



Note that as the carbon content goes up the brittleness goes up so the curve is flattened. As well, the DBTT rises. 52100 steel is 1% carbon steel with a low amount of chromium added. It begins to grow more brittle at around zero celsius.

Yes, too funny! 100Cr6 (BS: 2S135, 535A99; AFNOR: 100C6; SAE: 52100) is a ball bearing steel, for example. 1% carbon.
And now, Mr. FailingArgument, where is the 1% carbon line in your diagram? Is the lower transition point somewhere near PLUS 300 °F? And is the curve even more flat? Yes, almost flat, as you said!

May I quote from the PDF you posted?
"For steels, a CVN energy value of 15 ft-lbs is often taken as the onset value for brittle failure. Fig. 5.9 at 15 ft-lbs shows that for this criteria, steels with %C above around 0.5% would be considered brittle at room temperature."

So, well, that's what hardened steels are: Brittle. And compared to higher temperatures, the brittleness doesn't change considerably, because they are brittle by intent. And that even above room temperature. At 0.67% C it is (by the definition quoted) at PLUS 200 °F. PLUS! And that with just 0.67 % carbon.
And, Even, did you understand that the diagram actually shows the annealed state and not the hardened state that makes the steel even more brittle?


You are funny behind repair!

So please, don't bend your own cites to make them fit your ignorance. You quoted that and now it's your turn to actually understand it.


click! clickety-click! Damn, the ignore button seems to be intermittent.

No wonder that you even don't get that right. :D

Nick

Evan
10-02-2010, 05:28 AM
OH MY GOOD! How brainless is this argument?
If it cools slow, take more time. Thermal expansion rate is not size dependent, it only depends on the temperature difference.


Rate? Do you know what rate means? I did not mention rate. It is volumetric expansion that is in question here, not linear expansion. Oh oh, thinks Nick...

Also, the expansion is proportionately greater compared to the tolerances that must be achieved when fitting the parts. Oh oh says Nick again...



If it cools slow, take more time.

That is a good thing Nick. Another failure to understand.


And didn't you tell that it gets brittle a 0°C?


Didn't you even look at the graph?


And, Even, did you understand that the diagram actually shows the annealed state and not the hardened state that makes the steel even more brittle?


You really don't know anything about this topic. The annealed vs hardened state doesn't change the transition temperature at all.

What a waste of time.

vpt
10-02-2010, 09:28 AM
I was thinking about heating the outer housing in the oven and freezing the shaft for installation all at once.



This is how superchargers are assembled. They have a sequence where you have to heat and cool different parts and bearings multiple times to get everything together.

MuellerNick
10-02-2010, 10:29 AM
Rate? Do you know what rate means? I did not mention rate. It is volumetric expansion that is in question here, not linear expansion. Oh oh, thinks Nick...


Diameter is volumetric. I'm on a different planet than you.

Even, you tell such a huge pile of nonsense, that it doesn't make sense to answer it specifically.
What is sad about your POS is, that other readers here might believe in what you tell here.
If someone follows any discussion with you that starts with a wrong statement by Even, he will always discover the same pattern: Every argument against, is answered by pulling out of his hat a new rabbit (AKA buzz-word). Rabbit? In fact, it is a stinking fish. I only see a huge collection of half-knowledge that lacks any connections and background.

I don't try to argue with Mr. Knowsitall (electronics, metallurgy, gear construction, internal combustion engines, wood, gas bottles, ... whatever) because it is a useless discussion. I'm writing this only for those who like to understand how things relate to one another.


First, how obvious dumb Even's argument about brittleness is:
He says, that ball bearings shatter in Canada at the temperatures they have at a very special place. That's why they use plain bearings. But -how strange- the axles to not break, albeit they do have the same load and the same temperature. Don't forget, the spring is behind the bearing in the sequence track::wheel:bearing::spring::chassis. Go figure!
And, Even doesn't know, the steel part of a plain bearing is hardened too. 50 to 52 HRC when running on bronze. Ball bearings do have about 65 HRC. Both do use quite similar steels.

About brittleness, hardness, ductility and ultimate strength:
-------------------------------------------------------------------
[Keep in mind, a ball bearing (and even a plain bearing) are hardened.]

Brittleness: Is a dynamic property. It is mainly the ability to absorb energy without failure. Absorbing energy can be achieved by plastic deformation.
Brittleness changes with temperature. The plot looks a bit like one half of a hysteresis curve. It depends by all extend from the material. A material that is already brittle at a high enough temperature won't get much more brittle at lower temperatures. Obvious. And! the increase (if any) is very flat.

Hardness: Hardness is the resistance to withstand impacts without plastic deformation.

Ductility: Is the ability to withstand plastic deformation without failure (breakage)

Ultimate strength: The ability to withstand (pulling) force until failure. That may include a plastic phase right before failure. Some steels almost completely lack that plastic phase.

Now how does that work together?
A hardened material (ball bearing) has (almost) no ductility. It either springs back after some load or suddenly fails. HSS bits for example. They do have at about 55 HRC. Remember, BB's have about 65 HRC! As stated, brittleness is the ability to absorb energy (it's a dynamic property, Even denies that IIRC) by ductility. As you know, a hard material is not ductile, so it is brittle. And it is always brittle (below the annealing temperature). By hardening something, the ultimate strength increases. There is even an accepted relation between hardness and strength.

So if Even says BBs break at low temperatures because of brittleness, he forgot that they are brittle already at higher temperatures.

A closer look at ball bearings:
----------------------------------
Ball bearings (and tapered roller bearings, needle bearings, ...) do have a line contact. But only at a first glance!
It was Mr. Hertz who developed a formula that showed how deep the (temporary) impression a ball makes is. Interesting enough, the only material dependent parameter is the modulus of elasticity. You find the formula (http://de.wikipedia.org/wiki/Hertzsche_Pressung) here. The modulus of elasticity is material dependent. It is almost the same for all kinds of steels and at all temperatures. So the line contact becomes in fact a area contact. This is important to understand. Because now, we come to the point where hardness, ductility and ultimate strength play a role. The ball (or roller, ...) may not make a permanent (plastic) impression. If it does, the bearing is ruined right at that moment. Ductility does not serve here at all. It is just hardness that counts. And as I said above, hardness and ductility and ultimate strength do work hand in hand. An alloy for ball bearings does not have to be ductile, it has to be hard, has to have a high strength. The price is brittleness (at all temperatures). But as there is nothing in a BB that has to withstand plastic deformation, no one cares.
You might even try to bend a BB and see how much it plastically bends before it breaks. Wear eye protection!



Nick

tdmidget
10-02-2010, 11:21 AM
Evan , what railroad would that be?

MuellerNick
10-02-2010, 01:31 PM
Evan , what railroad would that be?


Must be this (http://www.youtube.com/watch?v=Ms3eBRmF57U) one.


Nick

Evan
10-02-2010, 01:47 PM
So if Even says BBs break at low temperatures because of brittleness, he forgot that they are brittle already at higher temperatures.


They become even more brittle at low temperatures. The curve isn't flat.

Roller bearing journals on railcars have significant problems here. A plain bearing can run 30 to 50 kilometres with a hot box. A roller bearing can be dead cold and then burn off the journal within 5 kilometres. This has caused numerous accidents because it was never detected. The hot box detectors are spaced about 30 kilometres on most lines.


The failure mechanism for truck bearings is usually not possible to determine as they are badly damaged. All bearing failures result in a hot box or burned off journal regardless of the initial reason for damage. As for determining how many cars still use plain bearing that information isn't available. Maybe some day I will take some pictures as the trains run 10 feet behind my wife's shop.

However, cold fractures are not uncommon. Even truck side frames fracture.


1.4.2 Other Documented Truck Side Frame Failures
Canadian Pacific Railway indicated that there have been five similar failures since 1994. These all occurred to truck side frames where roof liners were applied at Procor Limited. The ambient temperatures at the time of all five truck side frame failures were recorded to be below minus 20 degrees Celsius. All five truck side frames met Class B steel specifications and were manufactured between 1965 and 1975. Four of the failures resulted in derailments.

2.2.1.3 Material Properties
The material from the truck side frame did not meet all the requirements in the AAR specifications for truck side frames. Although the material was cast as Grade B steel, as required, the hardness and fracture toughness of the material were both below the minimum acceptable range. Furthermore, the minimum acceptable range is considered to be unsatisfactory, given the low ambient temperature experienced in the Canadian climate in the winter months and the susceptibility of such metal to brittle fracture at low temperatures.
http://www.tsb.gc.ca/eng/rapports-reports/rail/1997/r97t0075/r97t0075.asp

MuellerNick
10-02-2010, 02:16 PM
Roller bearing journals on railcars have significant problems here. A plain bearing can run 30 to 50 kilometres with a hot box. A roller bearing can be dead cold and then burn off the journal within 5 kilometres.

Moving targets!
How long did you explain the collected foolishness at HSM that those bearings break because of brittleness? And now, they burn!?
What will we read at page 15? Cryogenic treatment?

Wrong grease, contact the manufacturer. I think I said that 4 pages back.


However, cold fractures are not uncommon. Even truck side frames fracture.

Smoke grenades! Hat, rabbit, stinking fish!
Completely unrelated, you are once more just trying to distract from the subject of "brittle bearings". Don't tell us/me that the quoted side frames were hardened.

Fix your filter. Best would be, you filter yourself. :D

Nick

MCS
10-02-2010, 03:06 PM
I've got the FAG catalogue here.

It states:

"Deep groove ball bearings with lip seals can be used at operating temperatures from -30 C to 110 C, limited by the grease and sealing material"

Further they don't expand too much on minimum temperatures, although they give the operating range of "Multitop" grease as -40 C to 160 C.

Looks like, compared to the figures here, the manufacturers are also handing out BS.

Just because I grew utterly distrustful at forums I tend to believe and keep the printed version.

Evan
10-02-2010, 03:27 PM
Smoke grenades! Hat, rabbit, stinking fish!


How predictable of you. When you run out of facts then you start with the accusations.

This entire sidetrack by you is unrelated to the original point. You even provided proof that a bearing manufacturer imposes a lower temperature limit when installing bearings. I wonder why if it makes no difference?

No answer?

Evan
10-02-2010, 03:36 PM
"Deep groove ball bearings with lip seals can be used at operating temperatures from -30 C to 110 C, limited by the grease and sealing material"

Further they don't expand too much on minimum temperatures, although they give the operating range of "Multitop" grease as -40 C to 160 C.


It gets that cold here, never mind further north. We had -40 last winter. You have to be very careful when you start driving a vehicle because if you aren't almost anything might break. Even the tires are "square". Especially sensitive are springs which are very similar to bearing steels. It is common for various bearings in the engine accessories to screech for a few seconds when the engine starts. Certainly not good for them. Very cold conditions at start will produce spalling and brinelling at what are normally acceptable loads. Plane bearings have no such limitation. They warm up almost instantly and can run with insufficient lubrication for long periods. Crankshaft bearings are a good example. Have you ever seen what engine oil looks like at -40? It pours about like caramel.

John Stevenson
10-02-2010, 03:43 PM
With regards to using a hammer to install small bearings, the SKF mounting kit even includes a dead blow hammer....
http://www.mapro.skf.com/images/f_tmft36.jpg

Igor

Don't believe all you read even from the makers, can anyone spot whats wrong in the above picture ?

If we had fitted bearings this way we would have got a sharp smack about the head no mistake.

.

tdmidget
10-02-2010, 03:52 PM
Yes John. He driving on the outer race not the inner. Probably because they assigned a task to a photographer rataher than someone who knew what he was doing.

Evan
10-02-2010, 03:58 PM
Can you supply a car number?


When? I don't live by the tracks.

MCS
10-02-2010, 04:00 PM
Especially sensitive are springs which are very similar to bearing steels. .

Did a quick research on this statement.

Only the silicium percentage matches. Dissimilar are Carbon, Manganese and Chromium. Springsteel has Vanadium.

They are thus dissimilar, that's why the one is called ball bearing steel and the other spring steel.

Going back to "watch-car-crash-mode".

Evan
10-02-2010, 04:03 PM
Check out 1095 spring steel. Then check out 52100 bearing steel. The only significant difference is a low percentage of chromium.

MuellerNick
10-02-2010, 04:09 PM
This entire sidetrack by you is unrelated to the original point.

Who's the one pulling out new rabbits? Me?
Was it really me who pulled the rabbit .. er .. stinking fish with the truck frames?
Who came up with the $hit that the volumetric expansion is of interest when you are interested in the diameter? Me?
Smoke grenades that once more went off right in your head.


You even provided proof that a bearing manufacturer imposes a lower temperature limit when installing bearings. I wonder why if it makes no difference?

Selective reading? It doesn't help!
Read the posting with the three links to mfg data. Understand them! Next, accept that you don't completely understand German (nothing to be ashamed of). Read MCS's posting. Understand it!
Understand what 65 HRC means! Understand what the Charpy test measures and how it relates to ball bearings, NOT.

IT IS ALL ABOUT UNDERSTANDING.
Replicating buzz words and blindly shooting around with half-knowledge might impress some. But not all.


No answer?

There's only one answer to the POS getting bigger: Useless discussion.


Nick

ikdor
10-02-2010, 04:33 PM
Yes John. He driving on the outer race not the inner. Probably because they assigned a task to a photographer rataher than someone who knew what he was doing.

Well that's not really true, those kits support both the inner and outer race at the same time.

http://www.mapro.skf.com/images/f_tmft36dw.jpg

Igor

MCS
10-02-2010, 04:42 PM
Check out 1095 spring steel. Then check out 52100 bearing steel. The only significant difference is a low percentage of chromium.

For steel a significant difference is a significant difference.

The percentages X, Y, Z and on and on are alloying, not polluting, thus attributes to the specific behaviour. It's science.

Not Googling for similarities to a not-so-spring steel to a not-so-bearing steel and still have a not-so-important difference.

MuellerNick
10-02-2010, 05:09 PM
When you run out of facts ...

I don't run out of facts, you supply enough to show how wrong you are. :D


...then you start with the accusations.

How predictable you are. If you run out of arguments, you try switch over to a different discussion. After that moment, I add some vinegar to my arguments. You can avoid that by keeping focused.


Nick

lazlo
10-02-2010, 05:22 PM
Check out 1095 spring steel. Then check out 52100 bearing steel. The only significant difference is a low percentage of chromium.

1095 is plain carbon steel.

Springs are usually made from 5160 (alloy steel). But in either case, trucks, Cats, ATV's... are often driven/operated in arctic environments, complete with spring steel leaf springs and 52100 roller bearings.

AISI 52100 is 0.98-1.10% Carbon (C), 0.25-0.45% Manganese (Mn), 0.025%(max) Phosphorus (P), 0.025%(max) Sulfur (S), 0.15-0.30% Silicon (Si), 1.30-1.60% Chromium (Cr)
AISI 5160.. is 0.56-0.64% Carbon (C), 0.75-1.00% Manganese (Mn), 0.035%(max) Phosphorus (P), 0.040%(max) Sulfur (S), 0.15-0.30% Silicon (Si), 0.70-0.90% Chromium (Cr)

wierdscience
10-02-2010, 05:57 PM
Wow wading around in it knee deep here:)

Millions of bearings are driven in using pipe sleeves and hammers every year nearly all of them successfully by shade tree mechanics.Millions more are pressed in using bottle jacks,porta-powers,arbor and hydraulic presses nearly all of them successfully.

Millions are installed using,freon,dry ice,LPG and household refrigerator freezers along with bearing heaters,oil baths and torches.

Frankly it's not rocket science and it shouldn't be made out to be rocket science.

If you do a lot of bearings like I do then these are nice,they even make them with a handy built in thermocouple preset to 250F-

http://img.photobucket.com/albums/0903/wierdscience/czc.jpg

If not then the rules are simple,check dimensions on both the bearing and it's mount and apply force to which ever race is being installed.If both must be installed simultaneously then make up a driver/press tool.

beanbag
10-03-2010, 03:49 AM
Must be this (http://www.youtube.com/watch?v=Ms3eBRmF57U) one.


Nick

In America, "train" wouldn't rhyme with "again".

vpt
10-03-2010, 08:37 AM
It gets that cold here, never mind further north. We had -40 last winter. You have to be very careful when you start driving a vehicle because if you aren't almost anything might break. Even the tires are "square". Especially sensitive are springs which are very similar to bearing steels. It is common for various bearings in the engine accessories to screech for a few seconds when the engine starts. Certainly not good for them. Very cold conditions at start will produce spalling and brinelling at what are normally acceptable loads. Plane bearings have no such limitation. They warm up almost instantly and can run with insufficient lubrication for long periods. Crankshaft bearings are a good example. Have you ever seen what engine oil looks like at -40? It pours about like caramel.



It has been awhile but about 10 years ago now we had -55F. My truck was not happy at all. All kinds of things just snap off in your hands. It is a very very different environment when it is that cold.

Evan
10-04-2010, 08:25 AM
1095 is plain carbon steel.

Springs are usually made from 5160 (alloy steel). But in either case, trucks, Cats, ATV's... are often driven/operated in arctic environments, complete with spring steel leaf springs and 52100 roller bearings.


1095 is spring steel.


Search Results[PDF] Admiral Steel Spring Steel CatalogFile Format: PDF/Adobe Acrobat - Quick View
For accuracy, always refer to the decimal thickness when ordering! Hot Rolled As Rolled. Hot Rolled P&O Spheroidized Annealed. SAE/AISI 1095 Spring Steel ...

www.admiralsteel.com/pdf/catalog.pdf - SimilarSpring Steel, Coil Steel, Cold Rolled AnnealedTMT handles a large selection of colled rolled annealed spring steel. ... .010, 1050-1075-1095 .4080 .062, 1050-1075-1095, 2.529 .012, 1050-1075-1095 .4896 ...

www.tmtco.com/products/spring-steel-cold-rolled.html - Cached - Similar1095 spring steel diameter measuring tapes by Pi Tape Corporation ...Pi Tape Corporation's 1095 spring steel diameter measuring tapes are delivered with a Calibration Report traceable to the National Institute of Standards ...

www.pitape.com/outsidediametertape-1095springsteel.htm - Cached95 Carbon Spring Steel - Precision Steel Warehouse NINETY-FIVE CARBON, COLD ROLLED ANNEALED STRIP STEEL is the very finest of commercial quality (standard grade) High Carbon Spring Steel Strip available. ...

www.precisionsteel.com/spring-steel/95-carbon - Cached - SimilarAnnealed (spheroidized) Spring Steel - Mead Metals, IncSpheroidized Annealed Spring Steel Standard Specification to Steel, Strip, High-Carbon ... AISI - 1095 - SAE. Normalizing Temp. 1550 - 1650 F. 1550 - 1650 F ...

www.meadmetals.com/annealedspringsteel.htm - Cached - SimilarSpring Steel on ThomasNet.comCompany Profile: ISO 9001:2000 & ISO 9002 certified distributor of spring steel. Materials used include HR 1075/1080, HR 1095, CRA 1095 & HR 5160 steel. ..


For steel a significant difference is a significant difference.


Yes it is.
The chromium increases the high temperature strength. It actually reduces the low temperature toughness.


IT IS ALL ABOUT UNDERSTANDING.
Replicating buzz words and blindly shooting around with half-knowledge might impress some. But not all.


So far you haven't demonstrated even that much. You give yourself too much credit.

lazlo
10-04-2010, 08:33 AM
1095 is plain carbon steel.

Springs are usually made from 5160 (alloy steel). But in either case, trucks, Cats, ATV's... are often driven/operated in arctic environments, complete with spring steel leaf springs and 52100 roller bearings.

1095 is spring steel.

Search Results[PDF] Admiral Steel Spring Steel CatalogFile Format: PDF/Adobe Acrobat - Quick View

Admiral also calls 1035 (medium carbon steel) "Spring Steel". So are ball bearings similar to 1035 :rolleyes:

Like I said, automotive springs are made from 5160, and ball bearings are made from 52100. Many vehicles are operated daily in arctic conditions with no issues.

http://i164.photobucket.com/albums/u15/rtgeorge_album/AdmiralSteel.png

Evan, is this ridiculous rant about plain bearings being superior to roller bearings just so you can justify measuring a micron on your Southbend??

Evan
10-04-2010, 08:37 AM
I didn't mention vehicle leaf springs. You did.


Admiral also calls 1035 (medium carbon steel) "Spring Steel". So are ball bearings similar to 1035

I also didn't mention 1035 steel, you did.

leesr
10-04-2010, 02:37 PM
Please both you guy's are smart fellas.

Both of you let it go.

The original OP wanted advice on bearing installation.
I would say from my observations, that it is not recommended to freeze bearings below -120 Deg F, and definitely it is better to use a press. but for the home mechanic, it is done with soft tooling & a ball peen hammer.

I believe that a steel just like any material, that is taken to a low freezing temperature it is more likely it will have lower fracture critical properties.

this is a test for myth busters. yes.

what about install recommendations for bronze bearings ?

MuellerNick
10-04-2010, 04:05 PM
So far you haven't demonstrated even that much. You give yourself too much credit.


I didn't expect a different answer from a solipsist.


Nick

John Stevenson
10-04-2010, 05:19 PM
Right I'm going to play the bad guy and invoke Goodwins Law.

Evan and Nick sound like Hitler arguing against himself.

Now because the Hitler comparison has been made this thread is now finished.
protocol says whoever mentioned Hitler [ me] has lost. OK fine I wasn't arguing anyway.

So can you two Nazi's pack it in ? :D

oldtiffie
10-04-2010, 05:37 PM
You're right John.

It does seem to be a "Godwin's Law" situation.

http://en.wikipedia.org/wiki/Goodwin%27s_Law_Of_Usenet

But perhaps they need to be sent to "Brat Camp" or "Naughty Corner/Chair".

http://en.wikipedia.org/wiki/Brat_Camp

http://en.wikipedia.org/wiki/Naughty_chair

MuellerNick
10-04-2010, 06:37 PM
So can you two Nazi's pack it in ?

Just read the machine gun thread, then you know who's the one to blame.
Same pattern.


Nick

leesr
10-04-2010, 07:07 PM
You're right John.

It does seem to be a "Godwin's Law" situation.

http://en.wikipedia.org/wiki/Goodwin%27s_Law_Of_Usenet

But perhaps they need to be sent to "Brat Camp" or "Naughty Corner/Chair".

http://en.wikipedia.org/wiki/Brat_Camp

http://en.wikipedia.org/wiki/Naughty_chair

ok thats a bit ?

lazlo
10-04-2010, 07:30 PM
Nick, your Inbox is full :)

jugs
10-04-2010, 08:09 PM
Right I'm going to play the bad guy and invoke Goodwins Law.

Evan and Nick sound like Hitler arguing against himself.

Now because the Hitler comparison has been made this thread is now finished.
protocol says whoever mentioned Hitler [ me] has lost. OK fine I wasn't arguing anyway.

So can you two Nazi's pack it in ? :D

Here's an interesting word "Atychiphobia ". (pop it in google)

john
:)

RussZHC
10-04-2010, 09:16 PM
Though I enjoy a good discussion...curious as to why, unless I missed something, that no one has mentioned using some sore of retaining compound


http://bbs.homeshopmachinist.net/showthread.php?t=35091

as opposed to heat/cold or a hammer?

I don't dislike either of those options but if something of a delicate nature, maybe not OP question, still...

Arcane
10-04-2010, 09:59 PM
Here's an interesting word "Atychiphobia ". (pop it in google)

john
:)

Unfortunately, "I Beat Atychiphobia" on a T-shirt just doesn't have the same flair as....http://media.ebaumsworld.com/2006/07/ibeatanorexia.jpg

ADGO_Racing
10-04-2010, 11:24 PM
My vote is for Nick, he is the one actually making sense.:cool:

jim davies
10-05-2010, 12:18 AM
Bearings with ODs 2 1/2" or less [common in my world] can be driven on cold with suitable procedures. Sunnen pin fit oil or Hypoid gear lube makes a good lubricant. A press is far better than a hammer but most shops I have worked in didn't have much in the way of presses or drivers so the old swing press [2lb ball pein] was usually the tool of choice. I learned to use a bigger hammer and a heavy drift to reduce shock as much as possible. The combination bounces less and moves the bearing without great force. Never apply force through the rolling elements is an important rule to remember whatever method is used.

Either brass or steel is the best choice for a drift, take your choice. I have a large collection of both, with my usual favorite being a big, heavy cold chisel ground down to get maximum square contact with the bearing side.

The good thing about a brass drift is it is softer. The bad thing is the minute chips and dust that come off it in use. Steel is actually recommended by some axle gear manufacturers for that reason. I have a large collection of both. In my own shop, I make the effort to use a press and proper drivers. You need a lathe to make and keep shopmade drivers square.

As for railcar bearings, I spent a few years working at a chlorine plant and daily duty as a utility man was prepping the loaded 85 ton chlorine cars, as well as the tankcars that caustic soda was shipped in. Many of the old c/s cars had sleeve bearing trucks and we had to lift covers and fill them with oil from the 45 gallon drums provided. All the newer cars, and all the chlorine cars had sealed bearing trucks and they were shipped everywhere, including Alaska by barge. This was in the '70s. FWIW.

S_J_H
10-05-2010, 12:33 AM
Wow wading around in it knee deep here

Millions of bearings are driven in using pipe sleeves and hammers every year nearly all of them successfully by shade tree mechanics.Millions more are pressed in using bottle jacks,porta-powers,arbor and hydraulic presses nearly all of them successfully.

Millions are installed using,freon,dry ice,LPG and household refrigerator freezers along with bearing heaters,oil baths and torches.



Ain't that the truth!!
Some of the things I saw being done during my drag car days was just crazy.
When I was younger and less informed, I may have grabbed a hammer to seat a bearing race a time or 2. :cool:
Steve

MuellerNick
10-05-2010, 08:46 AM
Nick, your Inbox is full

Sorry, fixed it (forgot to delete old msgs).


Nick

Evan
10-05-2010, 11:41 AM
Here is an example of why it can be very expensive to hammer in a bearing that is frozen. If you don't recall that is what I said shouldn't be done. I didn't say bearings shouldn't be frozen, I said they should not be hammered in cold.

This is a chart from Timken showing the charpy impact energies for various annealed bearing materials. These materials are used to make bearings and are left in the annealed state. The material is then carburised to add the required carbon to the outer portion of the metal. The part is quenched which brings up the hardness to the necessary degree while still keeping the annealed core for toughness. Two of the steels have service temperatures that are well below freezing and would be used for extreme weather duty. The other would be the type used to make bearings such as high quality spindle bearings and similar machine bearings in general. As they will never see service even close to freezing the fact that the CBS1000M alloy loses over half it's strength at only the freezing point is of no consequence in service.

It is however of great consequence when installing the bearing frozen. This shows that unless you are certain of the material the bearing is made from you risk destroying the bearing if impact force is applied during installation of a frozen bearing.

http://ixian.ca/pics7/bearing9.jpg

paulx
10-05-2010, 12:32 PM
If your using temperature differential to install a bearing everything should just fall together.Having to resort to hammers and presses means something went wrong.

leesr
10-05-2010, 01:08 PM
If your using temperature differential to install a bearing everything should just fall together.Having to resort to hammers and presses means something went wrong.

I agree
Thermal treatments & assemble
press only after parts are at room temperature.

Bill Akins
10-05-2010, 02:56 PM
Just read the machine gun thread, then you know who's the one to blame.
Same pattern.


Nick

I've been a member here since 2008 and while I enjoy reading this site a lot, I am usually quiet and post rarely. But when I did post again recently, I experienced Evan doing the same thing that he does with Nick here.

Nick is correct about Evan if Nick is talking about my machine gun looking stock thread here....
http://bbs.homeshopmachinist.net/showthread.php?t=43926

Evan does a lot of the same pattern in my thread as he has here, just as Nick said he does. First Evan came into my thread, completely ignoring the subject matter of my thread and my initial post, and instead he starts hijacking my thread by talking about other subjects unrelated to the specific subject of my thread. In fact at first, Evan didn't even address the subject matter of my thread. He just wanted to hijack it to talk about other things that had nothing to do with the specific subject of my thread's build.

Then Evan makes outrageous and unscientific statements about my stock build that he cannot back up scientifically. He seems to think his OPINION replaces science. When I repeatedly asked him to substantiate his statements and explain them scientifically, Evan instead either ignored my questions or just diverted to another subject without ever explaining his previous statements scientifically. Finally he got so desperate because he had an indefensible position science wise, that he simply devolved into silly childish insults. Because that's all he had left.

Nick is correct. I see the same exact pattern here. Evan likes to argue with people, and thinks very highly of himself and that he is never wrong, but when you pin him down on something he is wrong about, he either ignores that, or changes the subject, or just gets insulting. Evan even insulted and called me a troll at my OWN THREAD! When it was he who came into my thread to try and hijack it!

Evan would not back up his statements he made at my thread by using science. He just ignored my logical science questions because he had an indefensible position that he could not back up scientifically. To him science doesn't matter and only his opinion does. At best he is a legend in his own mind, at worst he is a thread hijacking troll.

Nick is correct about him.


.

beanbag
10-05-2010, 03:09 PM
Bill, I am sorry that your thread got locked.
But please don't post only to complain about others.

Bill Akins
10-05-2010, 03:18 PM
Bill, I am sorry that your thread got locked.
But please don't post only to complain about others.

My thread got locked? I didn't know that. Well thanks to Evan and dp for being so disruptive and insulting I guess the mods locked it.

But beanbag, I am not posting here only to complain about others. I am posting here to confirm that what Nick was saying is true. Nick brought up that the same pattern Evan uses on him, Evan also used at my thread. I'm just confirming what Nick said is true.