After the bearing is installed, in order to check whether the installation is correct, an operation inspection must be performed. Small machinery can be rotated by hand to confirm whether it rotates smoothly. Inspection items include poor operation due to foreign matter, scratches, and indentations, unstable torque due to poor installation and poor machining of the mounting base, excessive torque due to too small clearance, installation errors, and sealing friction, etc. wait. If there is no abnormality, the power operation can be started.