Compare the Meerkat. How much does a breakdown cost? How much does a bearing cost? How much does one of the fancy bearing condition monitors cost? Simple.■

Originally Posted by sganesh

Dear Experts,

In the bearing catalogs, I can find out the bearing clearances

1) Before mounting

2) How much can be reduced during initial mounting

But they do not suggest, how long a bearing can be allowed to run as far as the clearances are concerned. Should I consider that the before mounting clearance as the maximum limit ? I feel it is not economical to replace the bearing as I feel that it has still life to be operated.

I need to balance between getting maximum life of bearings and before meeting the breakdowns.

Your valuable suggestions please.

Regards

==========================================================

Sganesh the bearing life depends on many parts to a single puzzle.

Assuming you have a castle nut and locking tab to secure the bearing:

!. With a cup and cone bearing set its simply a matter of installing the cup of the bearing and making sure it is fully seated as it is a press fit bearing.

and must be heated with a bearing heater or an oven to allow the slip fit to the bottom of the shoulder.

2. Then installing the cone which carries the bearings rollers and bearing sure it is fully in contact with the cup.

3. Then the next thing to do is tighten down the locking nut until you can no longer tighten it by hand and slightly more pressure with a punch and then locking down the tab against one face of the locking nut.

The cup and cone bearing allows a bit of leeway for adjustment to increase bearing life- the problem is deciding how long that bearing will last.

==========================================================

With roller bearings either ball, barrel, tapered barrel or double roller, barrel, double barrel, double tapered roller barrel sets everything is complete unless you buy roller ball bearings that allow you to install an additional ball.

the bearings are nested in the housings and locked in placed with a taper lock or key on the shaft and will run until they fail due to age and wear.

==========================================================

A bearings service life which is its B10 life depends on many things;

the type of bearing

that type of bearings B10 life

the lubricant being oill or grease

the mounting tolerances being a press fit or slip fit.

The application for that type of bearing.

The operating speed of the designed application as this affects the life of the bearing.

The proper installation of thet bearing no matter the type.

I always used spring pressurised grease cups to delver grease to bearings on conveyor belts for several reasons.

Much less grease is wasted reducing the mess from grease and its trapping dirt.

The bearings are not over greased which will blow out the seals and as long as grease is kept in the cup and not allowed to run out it will delver a measured amount only when the bearing is rotating.

I wish I could give you a single cut to fit answer but it is not possible. But I can telll you that the grease cups do work and save bearings from failure.

If you are using cup and cone bearings for all your applications i would suggest looking at a different bearing type to fit the size of the bearing housing-but it all depends upon the application, as you can not use a roller bearing on an axle housing for a mining scoop or an on the road truck.

lzaharis ■

Originally Posted by lzaharis

==========================================================

Sganesh the bearing life depends on many parts to a single puzzle.

Assuming you have a castle nut and locking tab to secure the bearing:

!. With a cup and cone bearing set its simply a matter of installing the cup of the bearing and making sure it is fully seated as it is a press fit bearing.

and must be heated with a bearing heater or an oven to allow the slip fit to the bottom of the shoulder.

2. Then installing the cone which carries the bearings rollers and bearing sure it is fully in contact with the cup.

3. Then the next thing to do is tighten down the locking nut until you can no longer tighten it by hand and slightly more pressure with a punch and then locking down the tab against one face of the locking nut.

The cup and cone bearing allows a bit of leeway for adjustment to increase bearing life- the problem is deciding how long that bearing will last.

==========================================================

With roller bearings either ball, barrel, tapered barrel or double roller, barrel, double barrel, double tapered roller barrel sets everything is complete unless you buy roller ball bearings that allow you to install an additional ball.

the bearings are nested in the housings and locked in placed with a taper lock or key on the shaft and will run until they fail due to age and wear.

==========================================================

A bearings service life which is its B10 life depends on many things;

the type of bearing

that type of bearings B10 life

the lubricant being oill or grease

the mounting tolerances being a press fit or slip fit.

The application for that type of bearing.

The operating speed of the designed application as this affects the life of the bearing.

The proper installation of thet bearing no matter the type.

I always used spring pressurised grease cups to delver grease to bearings on conveyor belts for several reasons.

Much less grease is wasted reducing the mess from grease and its trapping dirt.

The bearings are not over greased which will blow out the seals and as long as grease is kept in the cup and not allowed to run out it will delver a measured amount only when the bearing is rotating.

I wish I could give you a single cut to fit answer but it is not possible. But I can telll you that the grease cups do work and save bearings from failure.

If you are using cup and cone bearings for all your applications i would suggest looking at a different bearing type to fit the size of the bearing housing-but it all depends upon the application, as you can not use a roller bearing on an axle housing for a mining scoop or an on the road truck.

lzaharis

here is a link to mcmaster carr for the grease cups I mentioned

www.mcmaster/#grease-cups/=424cc9

Disclaimer

I have no financial or other affiliation with McMaster Carr inc. ■

Originally Posted by sganesh

Thanks a lot for a detailed reply.

Compared to production loss, the cost of bearing and the bearing checking instrument cost will be much lower.

I wanted to highlight ( hope I am right ) that there is no upper limit suggested for the tapered bore spherical roller bearings for their internal clearances.

When the bearing starts failing what will be it's first indication? Heat ? Noise ? Vibration?

Regards,

Greetings and salutations SGanesh,

The upper limit simply does not apply with a manually adjusted cup and cone bearing set as it is adjusted by hand and is allways a tight fit which allows for some take up-a cup and cone bearing set is used three ways typically as an exposed axle bearing that must be repacked periodically or an oil lubricated bearing in planetary axles or internal axle shaft support bearings in 4 wheel drive vehicles with out plantetary drives.

When a cup and cone bearing set fails it is a catastrophic failure with lots of noise and growling until it seizes and snaps a shaft or breaks a housing

leonz ■

Dear sganesh

Kindly , I try to help with using my site experience with that topics so :-

You didnt mentioned the application , rotation speed , etc..? , the upper limite or the indicatores of bearing is not matter than the mounting way

For taper bore bearing

Lets talk about shaft diameter 135 -- 140 mm

Bearing = 22230 MB SC3 K

Radial Clearance = Between 0.15... 0.2 mm

Direction of lock net tightening have to be revers to application rotation direction for fans , hummers , etc...

Tight till clearance equal to 0.17 ( just with new shaft ) and then adjust the lock net washer .

for start up you could find the grease ( less than 1000 rpm ) weight and type to add read the application operation instruc. manuals .

What we talked about is taper bore bearing and that deals with grease lubrication for majority. So the grade of grease must be as recomanded consistency .

In applications subject to vibration , the grease heavily worked as its continuously thrown back in to bearing by vibration , so that should used mechanically stable greases . the grease some how containing some water 1-2.5 % and that is a problem specially with high ambit temp.

Carefull with good monitoring and grease type selection will give you the max. life for you`re bearing .

For all of failures of sleeve bearing or taper bore bearing resultant on above reasons and that all .

Thanks ■

Adjusting tapered bore spherical roller bearings is not for the faint hearted. Is there any chance someone noted the original radial and / or axial clearances prior to disassembly? Please take into account that the radial clearance is indicative of the axial clearance since it is about 1/5 of it (1 over 5 ratio). This means that you have about for instance 0.2mm axial clearance if your radial clearance is 0.05mm. This can really mess up axial rotor clearances if the rotor is to clear housing parts. Also, you can take those readings only with a dial indicator whilst rotating the rotor . shaft back and forth a little - otherwise the rolling elements will not settle properly and indicate a false clearance. Do not use grease the taper or shaft prior to assembly; only use very light oil and wipe any excess lubricant off. The taper must fit really tight in the inner race of the bearing. Sometimes tapping the face of the shaft nut prior to using the spanner wrench helps moving the adjustment along.

figuring out what the original clearance was or needs to be is your first and most important job. Once you have figured that out you will be able to adjust the bearing.

Ralf ■

Dear Sirs.

Kindly I try to used the recommendation of bearings manufacturer at this time and I guess its very clear and helpful for new bearing again its for new assembly , please see what below :-

1-Check Shaft Tolerance .

2- Position adapter sleeve on shaft, threads outboard as indicated, to approximate location with respect to required bearing centerline. Micronized or powdered (not flaked) graphite or light oil applied to the sleeve outside diameter surface, results in easier bearing mounting and removal.

3-Measure the unmounted radial internal clearance in the bearing by inserting progressively larger feeler blades the full length of the roller between the most vertical unloaded roller and the outer ring sphere. Do not roll the feeler blade through the clearance: slide it through. Record the measurement of the largest size blade that will slide through. This is the unmounted radial internal clearance.

4-Mount bearing on adapter sleeve, starting with the large bore of the inner ring to match the taper of the adapter. With the bearing hand tight on the adapter, locate bearing to the proper axial position on the shaft. (Do not apply lockwasher at this time because drive up procedure may damage lockwasher.) .

Apply the locknut with the chamfered face toward the bearing. Use a lubricant on the threads and face of the locknut where it contacts the inner ring face of the bearing to make easier mounting for larger sizes. Larger size bearings will require a heavy duty spanner wrench and sledge hammer to obtain the required reduction in radial internal clearance. Do not attempt to tighten the locknut with hammer and drift. The locknut will be damaged and chips can enter the bearing. In larger bearing sizes it will be impossible to tighten the locknut far enough with a drift. If lower half of housing is in position, support the shaft such that the bearing outer ring is free to rotate. This will prevent internal damage to the bearing during tightening of the locknut. Remeasure internal radial clearance at this time. Tighten locknut and measure radial internal clearance with feeler blades between the most vertical unloaded roller and the outer ring sphere or at the 6:00 position if the

5-bearing is hanging free on the shaft, until the radial internal clearance is less than the measurement in Step 3 .

Remove locknut and mount lockwasher on adapter sleeve with inner prong of lockwasher toward the face of the bearing and located in the slot of the adapter sleeve. Reapply locknut until tight. (Do not drive bearing further up the taper as this will reduce the radial internal clearance previously secured. Check to make certain clearance has not changed.) Find lockwasher tang that is nearest a locknut slot. Bend one of the lockwasher tangs in a slot in the nut. If slot is slightly past tang, don’t loosen nut, but tighten to meet a washer tang.

6-Remove any paint and burrs from the mating surfaces at the split and thoroughly clean the housing. The vertical hole at the bottom of each enclosure groove must be free of foreign matter. Set lower halves of housings on base and oil the bearing seats. Place shaft with bearings into lower halves of housings, carefully guiding triple seals into the seal grooves and being certain that the bearing outer rings sit squarely in the pillow block bearing seats. Bolt the held housing securely in place. (The free bearing housing) will be located and bolted after completing and centering the free bearing in the free pillow block bearing seat .

7-The bearing seat in the upper half of the housing (cap) should be checked for burrs, thoroughly cleaned, oiled and placed over the bearing. Especially with oil lubrication, use of a sealing compound must be applied sparingly: wipe a thin film near the outer edges. Excessive amounts are forced not only out but also in between the housing bore and bearing O.D. and this can pinch an outer ring or make a free bearing actually held. The two dowel pins will align the upper half of the housing .

Thank you

Ali Awad ■

Dear Sirs.

Kindly I try to used the recommendation of bearings manufacturer at this time and I guess its very clear and helpful for new bearing again its for new assembly , please see what below :-

1-Check Shaft Tolerance .

2- Position adapter sleeve on shaft, threads outboard as indicated, to approximate location with respect to required bearing centerline. Micronized or powdered (not flaked) graphite or light oil applied to the sleeve outside diameter surface, results in easier bearing mounting and removal.

3-Measure the unmounted radial internal clearance in the bearing by inserting progressively larger feeler blades the full length of the roller between the most vertical unloaded roller and the outer ring sphere. Do not roll the feeler blade through the clearance: slide it through. Record the measurement of the largest size blade that will slide through. This is the unmounted radial internal clearance.

4-Mount bearing on adapter sleeve, starting with the large bore of the inner ring to match the taper of the adapter. With the bearing hand tight on the adapter, locate bearing to the proper axial position on the shaft. (Do not apply lockwasher at this time because drive up procedure may damage lockwasher.) .

Apply the locknut with the chamfered face toward the bearing. Use a lubricant on the threads and face of the locknut where it contacts the inner ring face of the bearing to make easier mounting for larger sizes. Larger size bearings will require a heavy duty spanner wrench and sledge hammer to obtain the required reduction in radial internal clearance. Do not attempt to tighten the locknut with hammer and drift. The locknut will be damaged and chips can enter the bearing. In larger bearing sizes it will be impossible to tighten the locknut far enough with a drift. If lower half of housing is in position, support the shaft such that the bearing outer ring is free to rotate. This will prevent internal damage to the bearing during tightening of the locknut. Remeasure internal radial clearance at this time. Tighten locknut and measure radial internal clearance with feeler blades between the most vertical unloaded roller and the outer ring sphere or at the 6:00 position if the

5-bearing is hanging free on the shaft, until the radial internal clearance is less than the measurement in Step 3 .

Remove locknut and mount lockwasher on adapter sleeve with inner prong of lockwasher toward the face of the bearing and located in the slot of the adapter sleeve. Reapply locknut until tight. (Do not drive bearing further up the taper as this will reduce the radial internal clearance previously secured. Check to make certain clearance has not changed.) Find lockwasher tang that is nearest a locknut slot. Bend one of the lockwasher tangs in a slot in the nut. If slot is slightly past tang, don’t loosen nut, but tighten to meet a washer tang.

6-Remove any paint and burrs from the mating surfaces at the split and thoroughly clean the housing. The vertical hole at the bottom of each enclosure groove must be free of foreign matter. Set lower halves of housings on base and oil the bearing seats. Place shaft with bearings into lower halves of housings, carefully guiding triple seals into the seal grooves and being certain that the bearing outer rings sit squarely in the pillow block bearing seats. Bolt the held housing securely in place. (The free bearing housing) will be located and bolted after completing and centering the free bearing in the free pillow block bearing seat .

7-The bearing seat in the upper half of the housing (cap) should be checked for burrs, thoroughly cleaned, oiled and placed over the bearing. Especially with oil lubrication, use of a sealing compound must be applied sparingly: wipe a thin film near the outer edges. Excessive amounts are forced not only out but also in between the housing bore and bearing O.D. and this can pinch an outer ring or make a free bearing actually held. The two dowel pins will align the upper half of the housing .

Thank you

Ali Awad ■

Dear Mr. Sganesh

I guess the attached will help you .

Warm thanks

Ali

Attachments

247573 (PDF)

■

Maybe invest in some equipment and training ---

http://www.skf.com/portal/skf/home/p...267044&lang=en ■