Crane grab is a kind of lifting equipment used to grab and carry bulk materials or large materials. It can be divided into many types according to the structure, driving mode and working object. It is widely used in ports, metallurgy, construction, mining and other fields. The following are the main classifications and their typical applications:
1. Classification by driving mode
Mechanical grab
Opening and closing are achieved by retracting and releasing the wire rope. The structure is simple and maintenance is convenient.
Application: Suitable for loading and unloading of general bulk materials (such as grain and coal).
Hydraulic grab
Driven by hydraulic cylinder, it has strong grabbing force, stable movement and strong controllability.
Application: Suitable for heavy materials (such as ore, scrap steel) or precision operations (such as garbage disposal).
Electric grab
Built-in motor drive, no external hydraulic system is required, suitable for occasions with convenient power supply.
Application: Commonly used for bulk material handling in fixed places such as power plants and docks.
2. Classification by structural form
Double-flap grab (double jaw plate)
The most common type, with two jaw plates designed symmetrically, is suitable for grabbing loose materials.
Application: Loading and unloading of bulk cargo such as coal, sand and gravel, and grain.
Multi-petal grab (multi-jaw plate, usually 4-8 petals)
Petal-shaped design, fits the surface of irregular objects when closed.
Application: Grabbing of large or sharp materials such as scrap steel, ore, and construction waste.
Wood grab
Jaw plate with sharp teeth to prevent wood from sliding.
Application: Loading, unloading and stacking of logs and round timber.
Shell grab
Good airtightness to prevent material scattering.
Application: Dust-like or easily contaminated materials (such as cement, chemical raw materials).
3. Classification by material characteristics
Light grab
Used for low-density materials (such as grain and fertilizer), light weight and large volume.
Heavy grab
Reinforced structure, wear-resistant design, suitable for high-density or sharp materials (such as iron ore and gravel).
Explosion-proof grab
Use explosion-proof motors or spark-free materials, used in flammable and explosive environments (such as chemical plants and granaries).
4. Match by crane type
Girder crane grab: commonly used in workshops and warehouses, used with electric hoists.
Gantry crane grab: the main equipment for loading and unloading bulk cargo at ports.
Marine crane grab: corrosion-resistant design, used for offshore material transfer.
Excavator grab: modified into a hydraulic grab, used for building demolition or material sorting.
5. Special purpose grab
Garbage grab: corrosion-resistant, with a sealed design, used in garbage incineration plants or landfills.
Electromagnetic grab: combined with electromagnetic suction cups, used for magnetic materials such as scrap iron.
Remote control grab: wireless control, suitable for high-risk or confined environments.
Application scenario examples
Port terminal: double-flap grab for loading and unloading coal, multi-flap grab for handling scrap steel.
Metallurgical industry: heavy-duty grab for transporting ore, hydraulic grab for cleaning slag.
Construction site: multi-petal grabs for cleaning up rubble, shell grabs for transporting cement.
Garbage disposal: anti-corrosion grabs for sorting garbage, remote-controlled grabs to avoid manual contact.
Selection points
Material characteristics: particle size, density, humidity, corrosiveness.
Operation frequency: wear-resistant and high-strength grabs are required for high-frequency operations.
Crane compatibility: matching the crane's lifting capacity, voltage and control system.
The correct selection of crane grabs can significantly improve operating efficiency and safety, and needs to be comprehensively evaluated in combination with specific working conditions.
