a thick film of lubricant between the journal and the bearing
In a hydrodynamic journal bearing , there is a thick film of lubricant between the journal and the bearing.
In hydrostatic lubrication, the load supporting high pressure fluid film is created by an external source like pump. The lubrication which is pressurized externally is supplied between the two surfaces. So, in hydrostatic lubrication the motion of one surface relative to other is not required.
the shaft tends to vibrate vigorously in transverse direction
Whirling speed is also called as Critical speed of a shaft. It is defined as the speed at which a rotating shaft will tend to vibrate violently in the transverse direction if the shaft rotates in horizontal direction. In other words, the whirling or critical speed is the speed at which resonance occurs.
Tearing strength of punched plate/ tearing strength of the solid plate
Tearing efficiency of a riveted joint is the ratio of = (Tearing strength of punched plate)/ (tearing strength of the solid plate)
D/T
Module Module is the length of pitch circle diameter per tooth. It is denoted by 'm'.
where m= d/T
d=Pitch circle diameter
T = Total number of teeths in gear
bending, torsion and thrust load
In lathe, the main spindle shaft holding the chuck is subjected to bending, torsion and thrust load.
