· 1, should the shaft/s be check for straightness. tolerance. For 1, probably if you have doubt regarding manufacture etc. For 2. Depends on length, bearing spacing, speed etc. It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts.
· supplied by two oil pumps, stops automatically if there is no oil; cooled by water, heating the motor firstly if start the machine in winter. lifting when changing or checking the spare parts which makes it easy and convenient in maintenance. brand SKF or TIMKEN of the bearing makes the machine work well and few problems.