Spiral continuous ship unloader is a type of efficient and continuous bulk cargo unloader that utilizes horizontal screw conveyors, vertical screw conveyors, and specially designed material retrieval devices as the main working mechanisms. An efficient continuous ship unloader that uses a mechanical rotation mechanism to lift and transport materials to the rear dock.
The screw unloader mainly consists of vertical arms, horizontal arms, rotating towers, end screw conveyors, and gantry components. The vertical arms include box shaped covers and vertical screw conveyors. The vertical screw conveyor is composed of an inner screw and an outer screw of the casing. The inner screw is used for vertical lifting of materials, and the outer screw is used for material loosening and feeding. The horizontal arm includes two parts: a box shaped arm frame and a horizontal screw conveyor.
When unloading the ship, the reverse spiral feeding device is first lowered into the material to be unloaded. The material is pushed downwards under the action of the forward spiral in the feeding device, and then the material is lifted towards the center by the feeding screw and squeezed at the reverse spiral. The reverse spiral transports the material to the spiral lifting pipe, and then the inner spiral lifts the material vertically. The material is then transported to the predetermined feeding point through a horizontal conveyor.
Advantages: Lightweight structure, completely sealed, good performance, can effectively prevent dust leakage and noise pollution, easy operation, low labor intensity of on-site personnel, and more suitable for unloading materials with poor fluidity (such as agglomerated materials). Compared with unloading ships with the same productivity, it has the lightest self weight.
What are the types of spiral continuous ship unloaders?
Spiral unloaders can be divided into three types based on whether the entire machine can be moved and the installation position: self-propelled, fixed, and floating. They are suitable for different dock loading and unloading process systems.
The characteristic of a self-propelled spiral ship unloader is that it has a walking mechanism and can walk along the track laid at the forefront of the dock. It uses the coordination of walking, turning, pitching, and swinging actions to unload the cargo hold of a seagoing ship. The unloaded materials can not only be unloaded onto the belt conveyor parallel to the dock shoreline, but can also be transferred onto the belt conveyor that can pitch around the hinge point at the end of the gantry, directly delivering the materials to the yard.
The self-propelled spiral unloader is suitable for coastal and inland ports with upright quay walls, targeting various bulk cargo ships. In the loading and unloading process system of specialized terminals for bulk cargo such as cement, fertilizers, grains, and coal, self-propelled screw unloaders have had many successful experiences and are increasingly proving to be an economical and efficient unloading equipment. Self propelled screw unloaders are also widely used in coal unloading operations at power plant docks.
The fixed screw unloader is directly installed on the pier pier pier. The ship unloader utilizes the coordinated actions of the rotating, pitching, and swinging mechanisms for unloading operations. The fixed spiral unloader is suitable for unloading materials from open barges in inland ports, and its operating range should meet the requirements of the ship’s width direction. The arrival of the unloading position in the captain’s direction can be achieved by moving the ship.
Floating screw unloaders are installed on barges and can be either fixed or mobile depending on their mobility. A floating movable screw unloader is installed on a floating flat bottomed pontoon dock or a floating transfer dock, and can move along the longitudinal track attached to the floating dock to unload or transfer ocean going cargo ships.