Luffing Mechanism and Operation Methods of Truck Crane

Luffing Mechanism and Operation Methods of Truck Crane

The amplitude mechanism is mainly used to extend or retract the double cylinder, make the boom elevation angle increase or decrease, achieving to change the working radius.

The boom elevation angle can vary from -2 degrees to 78 degrees. The -2 degree boom angle provides great convenience for overhauling the boom head parts. The joystick of the amplitude mechanism sets in the control room (see picture 5-1). The operation method is as follows.

Amplitude mechanism operation instruction
Push the level forward Boom decline
Pull the level backward Boom rise
Stop: move the level back to the neutral position, the boom stops.

There is balance valve in the hydraulic system, it not only can makes the landing smoothly, but also allows the boom to stay in any position.

1) Smooth operation is very important, the sharp operation will bring great impact to the crane when lifting a heave object.
2) If the work radius increases, accidents may be easily caused due to the overload, when lifting the object. The operator must limit maximum work radius according to the lifting characteristics table.
3) When the main boom unloaded extended fully, the minimum elevation angel must not be less than 20 degrees (the elevation angle can be read from the angle indicator).
4) Before lifting the boom, should fully lower the hook in advance.