- Practice · 5 marks
Types of rolling contact bearings
Short answer
Deep groove ball (radial+moderate axial, motors), angular contact ball (combined, spindles), self-aligning ball (radial, line shafting), thrust ball (axial, crane hooks); cylindrical roller (heavy radial, rolling mills), spherical roller (radial+axial, crushers), tapered roller (combined, wheel hubs), needle roller (radial, U-joints). Rolling bearings: low start friction, standardised, limited fatigue life; sliding bearings: high start friction, damp vibration, need continuous oil.
Name the main types of rolling contact bearings and state the load direction each can carry and one typical application. Differentiate between rolling contact bearings and sliding (journal) bearings.
A rolling contact (anti-friction) bearing supports a shaft through balls or rollers placed between an inner and an outer ring, so that sliding friction is replaced by rolling friction.
Main types
| Type | Load carried | Typical use |
|---|---|---|
| Deep groove ball | Radial, plus moderate axial in both directions | Electric motors, gearboxes, general machinery |
| Angular contact ball | Combined radial and axial (one direction; used in pairs) | Machine tool spindles, pumps |
| Self-aligning ball | Radial, allows shaft misalignment | Long shafts, line shafting |
| Thrust ball | Axial only | Vertical shafts, crane hooks |
| Cylindrical roller | Heavy radial, no (or little) axial | Large motors, rolling mills |
| Spherical roller | Heavy radial and some axial, self-aligning | Crushers, vibrating screens |
| Tapered roller | Heavy combined radial and axial (one direction; used in pairs) | Automobile wheel hubs, gearboxes |
| Needle roller | Radial in small space | Universal joints, compact gearboxes |
Roller bearings have line contact and carry higher loads than ball bearings, which have point contact and run faster with less friction.
Rolling and sliding bearings
| Point | Rolling contact bearing | Sliding (journal) bearing |
|---|---|---|
| Friction at start | Low, almost same at all speeds | High at start, falls when film forms |
| Load capacity at low speed | Good | Poor |
| Space | Small axial width, larger diameter | Small diameter, larger length |
| Noise | Noisier, especially at high speed | Quiet, damps vibration |
| Life | Limited by fatigue, predictable | Long when film is maintained |
| Shock load | Poor resistance | Good |
| Cost and standardisation | Standard and interchangeable, higher cost | Usually cheaper, custom made |
| Lubrication | Little, grease usually | Needs continuous oil supply |
✓ Answer checked by Claude Opus 5.5 (high effort)
Related questions
- Journal bearing design with film thickness check · Machine Design I, chapter 7
- Bearing life, load rating and equivalent load · Machine Design I, chapter 6
- APA and MLA: book and journal article · Communication English, chapter 4
- UDL transferred to main cable from point load · Theory of Structures I, chapter 7
- Arch 100 m rise 15 m: rolling UDL 10 m, section 60 m · Theory of Structures I, chapter 6
- Path of contact and contact ratio numerical · Theory of Mechanism and Machine I, chapter 4