Plain bearings Flashcards
Friction bearings or journal bearings are another name for:
plain bearings
This type of bearing has no rolling elements.
plain bearings
Plain bearings can either be 1._____________ bearings to support radial loads or 2._______________ bearings to support axial loads.
- journal
- thrust
What is the function of plain bearings?
to hold the journal in the required location and support the intended load
What is another name for a thrust load?
an axial load
The _______________ is the part of the shaft in contact with a bearing.
journal
On a plain bearing, a shaft collar is used in conjunction with a ___________ bearing.
thrust
What are shaft collars also known as?
thrust collar and runners
How can axial force be controlled in both directions when using a plain thrust bearing?
by using one collar sandwiched between two thrust bearings
What is the term bearing, or journal bearing used to describe when talking about plain bearings?
the bushing or shell that fits around the outside of the journal
True or false:
The term bearing typically describes a radial type of load.
true
- generally the axial or thrust component would be mentioned
What type of bearing is used to locate a shaft in a specific axial position without interfering with the shafts rotation?
a thrust bearing
What two components make up linear bearings?
- guide or rail
- bushing or carriage
Why are bearings usually made of softer materials than the shaft journals that they support?
to make the bearing the sacrificial component
What material are shaft journals usually made of?
the same material as the shaft, just machined to a tighter tolerance
True or false:
Bearing material must be strong enough to support the shaft loads at minimum operating temperatures.
false;
at maximum operating temperatures
What effect does wear resistance have on the compressive strength of a bearing?
wear resistance ↓ = compressive strength ↑
This type of bearing resistance is resistance to cracking and flaking by loads that increase and decrease in rapid cycles.
fatigue resistance
How is fatigue resistance of a journal bearing increased?
by keeping the liner material as thin as possible to allow the backing to absorb the stresses
When it comes to bearings, what is embeddability?
how well the bearing material handles contaminants without failing
True or false:
A bearing material with high embeddability allows abrasive contaminants to become embedded into the bearing material.
true
What effect does compressive strength have on the embeddability of a bearing material?
compressive strength ↑ = embeddability ↓
This journal bearing material characteristic allows the material to yield to misalignment or imperfections in the shaft.
deformability/conformability
When referring to the conformability of bearing material, this is referring to:
the deformability
conformability = deformability