What is the difference between sn and SNK of vertical bearing seat?

Sn is equal diameter pass bearing seat (bearing seat with equal holes at both ends), SNK is reducing diameter pass bearing seat (bearing seat with unequal holes at both ends)

The bearing seat is scientifically defined as a member installed on the body or foundation of the turbine cylinder to support the bearing. In the conveyor belt machinery industry can not lack the bearing seat. Since the bearing seat is so important, do you know the role of the bearing seat?

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The bearing seat is used to support the bearing, fixing the outer ring of the bearing, only allowing the inner ring to rotate, the outer ring remains stationary, always in line with the direction of transmission (such as the direction of motor operation), and maintain balance. The concept of bearing is an assembly of bearing and box body, which is easy to apply. The advantage of the bearing is that it can have better coordination and convenient use, and the cost of using the manufacturer is less. A variety of shapes, usually a box bearing, can be mounted in it.