Automotive Calculating radial and axial loads for a tapered roller bearing

AI Thread Summary
The discussion focuses on calculating radial and axial loads for a tapered roller bearing in a differential system, specifically with an input torque of 333.5 N-m at 4000 RPM. The user initially attempts to derive the radial force using torque and bore radius but realizes the need for a more accurate approach, emphasizing the importance of the bearing's position and pitch radius. It is noted that pinion bearing selection often relies on experience rather than strict calculations, with pre-loading being crucial for maintaining pinion alignment. The conversation also highlights the necessity of understanding the 3D position and direction vector of the pinion contact area to accurately resolve forces on the bearings. Resources for further guidance on this topic are suggested, though some may require payment.
voyager14
Messages
2
Reaction score
0
Hi

I'm analyzing a tapered roller bearing as part of a differential. I know the shaft is providing input torque of 333.5 N-m @ 4000RPM, and I know the bore size of the bearing, 30mm. I need to find the radial and axial forces given that torque, so I can move on to finding C10, L10, rated load, and lifetime.

I've tried:
1. Diving torque by bore radius (which I realized is tangential force, which is different)
2. Using
Fr = m(ω)2r
where
ω = (RPM/60)2π
this got me
Fr = 1052N or 1.052kN

I don't know if that's correct, and I could also use help with the axial force.
Thank you.
 
Engineering news on Phys.org
If the tapered roller bearing is one of two on the input shaft to the pinion, then the pitch radius of the pinion, and the position of the two bearings will be important.

If the tapered roller bearing is one of the two that supports the differential assembly in the carrier, (axial with the axle shafts), then the pitch radius of the crown wheel will be important.

You will need to know the profile and the offset of the hypoid pinion and crown to resolve the axial forces.
 
Baluncore said:
If the tapered roller bearing is one of two on the input shaft to the pinion, then the pitch radius of the pinion, and the position of the two bearings will be important.

If the tapered roller bearing is one of the two that supports the differential assembly in the carrier, (axial with the axle shafts), then the pitch radius of the crown wheel will be important.

You will need to know the profile and the offset of the hypoid pinion and crown to resolve the axial forces.

Thank you. It is one of the bearings on the input shaft to the pinion. Are there any resources you know of to help walk me through this?
 
voyager14 said:
Are there any resources you know of to help walk me through this?
I don't know of a reference, but will take a look.

Pinion bearing selection is not normally a computed parameter, it has evolved through experience. If it fails, differential manufacturers will use the next bearing up, if it never fails, try the next smaller bearing.

Radial and axial thrust may not be the critical selection parameters. The pinion bearings are always pre-loaded against each other, in order to hold the pinion in a well defined position relative to the crown wheel.

If you know the 3D position and direction vector, normal to the pinion contact area on the crown, you should be able to solve the vector problem to find the forces on the two bearings due to the input shaft torque.
 

Thread 'HP Required to move a robot 10meters at 1.5m/sec'

I need some assistance with calculating hp requirements for moving a load. - The 4000lb load is resting on ball bearing rails so friction is effectively zero and will be covered by my added power contingencies. Load: 4000lbs Distance to travel: 10 meters. Time to Travel: 7.5 seconds Need to accelerate the load from a stop to a nominal speed then decelerate coming to a stop. My power delivery method will be a gearmotor driving a gear rack. - I suspect the pinion gear to be about 3-4in in...
View full post »
Thread 'Calculate minimum RPM to self-balance a CMG on two legs'

Thread 'Calculate minimum RPM to self-balance a CMG on two legs'

Here is a photo of a rough drawing of my apparatus that I have built many times and works. I would like to have a formula to give me the RPM necessary for the gyroscope to balance itself on the two legs (screws). I asked Claude to give me a formula and it gave me the following: Let me calculate the required RPM foreffective stabilization. I'll use the principles of gyroscopicprecession and the moment of inertia. First, let's calculate the keyparameters: 1. Moment of inertia of...
View full post »
Thread 'Turbocharging carbureted petrol 2 stroke engines'

Thread 'Turbocharging carbureted petrol 2 stroke engines'

Hi everyone, online I ve seen some images about 2 stroke carbureted turbo (motorcycle derivation engine). Now.. In the past in this forum some members spoke about turbocharging 2 stroke but not in sufficient detail. The intake and the exhaust are open at the same time and there are no valves like a 4 stroke. But if you search online you can find carbureted 2stroke turbo sled or the Am6 turbo. The question is: Is really possible turbocharge a 2 stroke carburated(NOT EFI)petrol engine and...
View full post »

Similar threads

How to obtain Axial Load Capacity from Tapered Roller Bearings Catalog
Replies
4
Views
2K
Tapered Roller Bearing - Static Radial Rating
Replies
1
Views
1K
Calculate the radial force acting on bearings in a carousel
Replies
3
Views
3K
Bearing loads for roller skates or skateboards
Replies
2
Views
3K
Bearing requirements calculation
Replies
2
Views
1K
How to calculate the applied radial load on a bearing?
Replies
5
Views
8K
Torque calculations: Rotating vertical shaft
Replies
5
Views
5K
Calculating the normal force due to moment load on a thrust bearing
Replies
5
Views
3K
Bearing Basics: Axial, Radial, & Tangential Loads
Replies
5
Views
4K
Are Axial Forces on a Drive Shaft Negligible in Bearing Design?
Replies
2
Views
11K

Hot Threads

Recent Insights

Back
Top