Product Introduction

Working principle

When the material is being excavated, the coal stacker remains stationary and continuously cuts and collects the material by the combined movement of the rotating front bucket wheel and the rotating arm. When the bucket rotates to a certain height, the materials fall onto the receiving conveyor belt under the effect of gravity, and then are discharged from the bucket onto the unloading conveyor belt. They are then transported to the designated location by trucks or other conveying systems. After one layer of excavation is completed, the machine moves forward or the boom descends to dig the next layer. The depth of material removal is controlled by the machine's forward movement or the extension of the boom, while the excavation width is determined by the rotational speed. The traveling function of the excavator is an auxiliary function. Its operation is continuous. The bucket is specifically used for digging, and the material transportation is managed by the conveyor belt.

Structural features

The coal stacker crane is composed of six major systems: the traveling system, the rotating system, the working system, the conveying system, the electric drive system and the hydraulic system. The main features include:

(1) Travel system

Most modern coal stackers adopt crawler traveling systems, while a few use traveling mechanisms. Small and medium-sized coal stackers usually adopt a double-track configuration, while large excavators use a multi-track design (three tracks or four tracks) to reduce the specific pressure on the ground.

(2) Rotary system

This platform consists of a rotary platform and drive components, and is equipped with a power unit, drive mechanism, control equipment and a cab inside. The drive assembly is equipped with slewing bearings and can rotate 360° around the vertical axis.

(III) Work System

It is composed of a bucket wheel, a boom, a luffing mechanism and driving components. The bucket wheel is a rotating wheel with evenly distributed buckets, installed at the front end of the boom. The boom is hinged to the gantry frame of the platform and adjusted through steel wire ropes or hydraulic cylinders to position the bucket wheel on the excavation plane. The length of the boom can be fixed or extended. The bucket wheel drive unit (including the motor, safety coupling and reducer) is installed on the front side of the boom to provide power for rotation.

(4) Conveying system

It includes the receiving conveyor belt, the hopper and the unloading conveyor belt. The bridge excavator is also equipped with a transfer conveyor belt on the bridge structure.

(5) Electric drive system

All units are equipped with externally powered frequency converter systems.

(6) Hydraulic system

The luffing of the boom and the positioning of the unloading boom are mainly driven by the hydraulic cylinder.