Specifications

Thrust ball bearing 51108
1.Purely axial loads
2.Single/Double direction
3.High Grade Balls
4.ISO:9001:2000

Thrust ball bearing in single direction 51108 bearing

Ball Bearing

A ball bearing is a type of rolling-element bearing that uses balls to maintain the separation between the bearing races.The purpose of a ball bearing is to reduce rotational friction and support radial and axial loads. It achieves this by using at least two races to contain the balls and transmit the loads through the balls. In most applications, one race is stationary and the other is attached to the rotating assembly (e.g., a hub or shaft). As one of the bearing races rotates it causes the balls to rotate as well. Because the balls are rolling they have a much lower coefficient of friction than if two flat surfaces were sliding against each other.

Ball bearings tend to have lower load capacity for their size than other kinds of rolling-element bearings due to the smaller contact area between the balls and races.However, they can tolerate some misalignment of the inner and outer races.

 Thrust bearing

A thrust bearing is a particular type of rotary bearing.Like other bearings they permit rotation between parts, but they are designed to support a high axial load while doing this.Thrust bearings come in several varieties.

Thrust ball bearings,composed of ball bearings supported in a ring, can be used in low thrust applications where there is little axial load.

Cylindrical thrust roller bearings consist of small cylindrical rollers arranged flat with their axes pointing to the axis of the bearing.They give very good carrying capacity and are cheap,but tend to wear due to the differences in radial speed and friction which is higher than with ball bearings.

Tapered roller thrust bearings consist of small tapered rollers arranged so that their axes all converge at a point on the axis of the bearing. The length of the roller and the diameter of the wide and the narrow ends and the angle of rollers need to be carefully calculated to provide the correct taper so that each end of the roller rolls smoothly on the bearing face without skidding.These are the type most commonly used in automotive applications (to support the wheels of a motor car for example),where they are used in pairs to accommodate axial thrust in either direction, as well as radial loads.They can support rather larger thrust loads than the ball type due to the larger contact area, but are more expensive to manufacture.

Spherical roller thrust bearings use symmetrical rollers of barrel shape,rolling inside an outer race with a spherical inner surface.They can accommodate combined radial and axial loads and also accommodate misalignment of the shafts.They are often used together with radialspherical roller bearings.Fluid bearings, where the axial thrust is supported on a thin layer of pressurized liquid—these give low drag.Magnetic bearings, where the axial thrust is supported on a magnetic field.This is used where very high speeds or very low drag is needed, for example the Zippe-type centrifuge.They are commonly used in automotive,marine,and aerospace applications.

Thrust bearings are used in cars because the forward gears in modern car gearboxes use helical gears which, while aiding in smoothness and noise reduction,cause axial forces that need to be dealt with.The double helical or herringbone gear balances the thrust caused by normal helical gears.One specific thrust bearing in an automobile is the clutch "throw out" bearing, sometimes called the clutch release bearing.

Thrust ball bearings consist of two precision chrome steel washers (ring) and a ball complement spaced by bronze retainer. They can be supplied with or without radius ball grooves in the rings. Thrust bearings are used under purely axial loads.

Thrust ball bearings are classified into those with flat seats or aligning seats depending on the shape of the outer ring seat (housing washer). They can sustain axial loads but no radial loads.For Single-Direction Thrust Ball Bearings, pressed steel cages and machined brass cages are usually used The cages in Double- Direction Thrust Ball Bearings are the same as those in Single-Direction Thrust Ball Bearings of the same diameter series.

Thrust Ball Bearing is separable,which can only carry axial load.The single direction bearings of them can only carry axial load in one direction,while the double can carry alternating axial load in either direction.Before using they have to be preloaded.The thrust ball bearings are used in lathe centers,automobile clutches,reducers and so on.The double direction angular contact thrust ball bearings are suitable for machine tool spindles,while the single are used to support ball screws.

Thrust ball bearings are produced as single direction or double direction thrust ball bearings.They are designed to accommodate axial loads only and must not be subjected to any radial load. 
Thrust ball bearings are separable, i.e. the shaft washer,housing washer(s), ball and cage assembly(s) can be mounted separately. Shaft washers have a ground bore to enable an interference fit.The bore of the housing washer is turned and always larger than the shaft washer bore.

Single direction thrust ball bearings

single direction thrust ball bearings consist of a shaft washer,a housing washer and a ball and cage assembly (fig 1).As their name implies,single direction thrust ball bearings can accommodate axial loads and locate a shaft axially,in one direction only.

Double direction thrust ball bearings

double direction thrust ball bearings consist of one shaft washer,two housing washers and two ball and cage assemblies (fig 2). The housing washers and ball and cage assemblies are identical to those found in single direction bearings.Double direction thrust ball bearings can accommodate axial loads and locate a shaft axially, in both directions.

 

Thrust ball bearings with sphered housing washers

 

To accommodate initial misalignment between the shaft and housing, KLT supplies both single and double direction thrust ball bearings with sphered seat surfaces on the housing washers (fig 3).They can be used together with a sphered seat washer adjacent to the housing washer (fig 4 and fig 5) or adjacent to a machine component manufactured with asphered surface. 
Appropriate sphered seat washers must be ordered separately. Depending on the bearing series, they have the basic designation U 2, U 3 or U 4 followed by a two-digit number,which identifies the size (e.g.sphered seat washer U 320 for bearing 53320).

Features

 

Available in two designs: single direction and double direction.

 

To accommodate initial misalignments in an assembly both designs are available with spherical aligning seats or aligning seat washers.

 

High quality steel-ultra clean steel to extend bearing life by up to 80%.

 

Advanced Grease Technology - KLT  lubricants that can extend grease life and performance.

 

High Grade Balls - Quiet and smooth operation even at high speed.

 

Parts  models of Thrust Ball Bearings

Axial Load Thrust Ball Bearings:

NO.	d(mm)	D(mm)	H(mm)	Weight(kg)
51100	10	24	9	0.0193
51101	12	26	9	0.0214
51102	15	28	9	0.0243
51103	17	30	9	0.0253
51104	20	35	10	0.038
51105	25	42	11	0.056
51106	30	47	11	0.066
51107	35	52	12	0.083
51108	40	60	13	0.12
51109	45	65	14	0.15
51110	50	70	14	0.16
51111	55	78	16	0.24
51112	60	85	17	0.29
51113	65	90	18	0.324
51114	70	95	18	0.36
51115	75	100	19	0.392
51116	80	105	19	0.433
51117	85	110	19	0.46
51118	90	120	22	0.655
51120	100	135	25	1
51122	110	145	25	1.08
51124	120	155	25	1.2