Main mechanisms of dock slewing fixed crane

The structure of dock slewing fixed crane generally includes: 2 sets of lifting mechanisms; 1 set of variable-length mechanism; 2 sets of rotating mechanisms; 1 set of hooks; 1 set of double-rope grab buckets; 1 set of foundation steel embedded parts; 1 set of electronic control system; 1 set of lubrication system.

Lifting mechanism

The performance of the lifting mechanism fully meets the technical requirements of the buyer and the requirements of actual use. The lifting mechanism consists of variable frequency motor → flexible coupling → brake → reducer → toothed coupling → wire rope drum (including wire rope pressure device). Two sets of lifting mechanisms are used to adapt to the working conditions of hooks and grab buckets.

The electronic control device of the lifting mechanism has good speed regulation performance, and uses variable frequency speed regulation to meet the requirements of lifting speed under different lifting weights. The winding of the lifting wire rope and the arrangement of the pulley group are conducive to the replacement of the wire rope and the improvement of the service life of the wire rope, and the winding method is adopted. The drum is single-layer winding, and is equipped with a good performance wire guide and rope pressure device to prevent the wire rope from loosening and jumping. In order to reduce the jumping of the wire rope, rubber pads are arranged along the boom. It is equipped with a double hydraulic disc brake, which has good heat dissipation and a stable friction coefficient. It can ensure accurate and safe stopping at any height position during long-term busy use.

The lifting mechanism is equipped with safety interlock protection devices such as lifting weight detection, position limit of lifting height and lowering depth, and speed limit.

When the rated load is lifted to 95%, there is an audible and visual alarm. When the rated load reaches 110%, the protection device cuts off all controllers and only allows the cargo to be lowered.

Luffing mechanism

Rack type: single arm or four-link combination arm. The luffing mechanism adopts AC frequency conversion speed regulation, the luffing drive device adopts gear rack transmission, the arm self-weight balance adopts lever-live counterweight type, and the counterweight in the balance beam adopts a removable cast iron block. The drive of the luffing mechanism consists of a variable frequency motor → coupling → double disc brake → reducer → gear and rack. The luffing mechanism is equipped with a maximum and minimum amplitude limit device, and a maximum and minimum amplitude front deceleration limit protection device to ensure the safety of equipment and personnel during work. The luffing mechanism is equipped with a buffer with good performance. The layout of the luffing mechanism takes into account the convenience of installation, adjustment, maintenance and maintenance.

Wire rope type: The luffing device consists of a set of independent hoisting devices, namely: motor → coupling (including brake) → reducer → wire rope drum.

The luffing mechanism adopts a rotor series resistance speed regulation system, which has good speed regulation performance, ensuring uniform luffing speed, smooth operation, reliable operation, convenient maintenance and low noise.

In order to reduce the power loss of the boom and improve the operating performance of the crane, a wire rope compensation system is used in the mechanism to ensure that the cargo is approximately horizontally shifted within the entire range of the boom.

The boom brake has sufficient braking torque and safety factor. Within the boom range, when the boom is in any position in the space, it can be safely positioned and braked. The braking device is flexible, safe and reliable.

The boom mechanism is equipped with a limit switch with good performance, reliable use, and automatic stop when the boom reaches the maximum and minimum amplitudes;

During maintenance, the boom can be placed at a height of 1 meter on the dock surface to repair the boom head.

Rotating mechanism

This mechanism consists of a set of rotating support devices and two sets of rotating drive devices. The rotating support device adopts a three-row roller slewing bearing; the rotating drive device consists of a motor → coupling → foot-operated variable frequency variable force brake → vertical planetary reducer → output shaft → open pinion → slewing bearing outer gear ring (external meshing). It is also equipped with electric centralized lubrication to force lubricate the rotating support.

This mechanism works smoothly, safely and reliably, and can rotate 360° forward and reverse. A rotating anchor device is provided and interlocked with the rotating mechanism. The unevenness, inclination and stiffness of the upper and lower bearing surfaces of the slewing bearing meet the assembly accuracy requirements of the slewing bearing. A latch-type rotating anchor device is installed between the rotating part and the door column, and two anti-rotation anchor sockets are provided on the cylinder.

Lubrication system

The whole machine is provided with a set of electric centralized lubrication devices, including the slewing and upper pulleys and booms, etc., to provide reliable and effective lubrication conditions for bearings, gears, pulleys and other moving parts. The intelligent centralized lubrication system has a signal that can be sent by the crane control system to the centralized lubrication system to start or stop, realizing remote control. At the same time, the total fault signal of the centralized lubrication system can be fed back to the crane control system for reporting, so as to facilitate the query and processing of relevant personnel.