What is a slewing bearing used for?
A slewing bearing or slew[ing] ring (also called a turntable bearing) is a rotational rolling-element bearing that typically supports a heavy but slow-turning or slowly-oscillating loads in combination (axial, radial and moment loads), often a horizontal platform such as a conventional crane, a swing yarder, or the …
How do you test a slewing bearing?
One of the most basic indicators of slewing ring bearing problems is the condition of the lubricant. If metal particles or flakes are apparent, some form of wear is taking place. Grinding, popping, or clicking noises from the bearing typically mean there is inadequate lubrication and/or excessive wear in the raceway.
What is a slewing gear?
A slew drive is a gearbox designed to handle radial or axial loads using high rotational torque. A descendant of the “worm” screw, slewing drives are present in construction machinery, manufacturing, military equipment and many other applications that require strength and precision.
What is slewing in Crane?
Slewing is the rotation of an object around an axis, usually the z axis. An example is a radar scanning 360 degrees by slewing around the z axis. This is also common terminology in astronomy. In crane terminology, slewing is the angular movement of a crane boom or crane jib in a horizontal plane.
What is rocking test of Crane & how frequently you should perform it?
every six months
-‘Rocking tests’ are carried out every six months and that the results are recorded and monitored in order to ensure the wear tolerances remain within the limits. – The ship is adjusted to have least possible trim, preferably on even keel. – Bad weather / Windy situations are avoided.
What is Crane rocking test?
The rocking test comprises the measurement of the deflection between the crane pedestal and the rotating crane housing in the way of the slewing ring using a dial test indicator to determine the bearing clearances.
What is luffing and slewing?
The ability to lift and slew a load is common to all cranes. To luff means to move the jib of a crane vertically to lift a load. A luffing jib moves under power (hydraulic or cable) with a load or into a working angle to lift a load.
What is crane rocking test?
