Amount of grease
The amount of grease used in any given situation will depend on many factors relating to the size and shape of the housing, space limitations, bearing’s rotating speed and type of grease used. As a rule of thumb, bearings should be filled to 30 to 40% of their space and housing should be filled 30 to 60%. Where speeds are high and temperature rises need to be kept to a minimum, a reduced amount of grease should be used. Excessive amounts of grease cause temperature rises which in turn cause the grease to soften and may allow leakage. Oxidation and deterioration of excessive grease fills may cause the lubricating efficiency to be lowered. Moreover, the standard bearing space can be found by formula (11.1)
V ＝ K ・ W …………………………… (11.1)
where,
V : Quantity of bearing space open type(approx.), cm3
K : Bearing space factor (see value of K in Table 11.4)
W : Mass of bearing, kg
A predetermine amount of grease is filled in the bearing with a grease gun or a syringe. After sealing it is not possible to spread the grease by hand - only by rotating the bearing by hand.
