How does an excavators strong magnetic chuck work

 1. Electromagnetic strong magnetic chuck (the most common type)
Its core is to generate a magnetic field using electric current, and realize "attraction" and "release" by controlling the on-off of the current.  
- Structural composition: It mainly includes a chuck panel (made of magnetically conductive materials, such as low-carbon steel), internal coils (wound with copper wires), a shell (non-magnetically conductive material to prevent magnetic leakage), and a control system (solenoid valve, cable, etc.).  
- Working process:  
  - Attraction phase: When the excavator's hydraulic system or a dedicated power supply supplies power to the chuck coil, the current passes through the coil to generate an electromagnetic field. The magnetic field forms a closed magnetic circuit through the magnetically conductive panel, making the surface of the panel generate strong magnetic force, thereby firmly attracting ferromagnetic metal materials.  
  - Release phase: When the power supply to the coil is cut off, the electromagnetic field disappears, and the magnetic force weakens accordingly (or rapid demagnetization is achieved through reverse current), causing the materials to fall off under the action of gravity.  
- Characteristics: The magnitude of the magnetic force can be controlled by adjusting the current intensity, and the attraction/release operations are flexible, making it suitable for scenarios that require frequent loading and unloading.

 2. Permanent magnetic strong magnetic chuck
It relies on the inherent magnetic force of permanent magnets (such as neodymium-iron-boron magnets) and controls attraction and release by changing the direction of the magnetic field through a mechanical structure.  
- Structural composition: High-strength permanent magnets are embedded inside, along with a rotatable magnetic circuit switching device (such as a yoke) and an operating handle/hydraulic push rod.  
- Working process:  
  - Attraction phase: Through mechanical or hydraulic control, the magnetic field path of the permanent magnet is conducted through the chuck panel, forming a strong magnetic area to attract metal materials.  
  - Release phase: The switching device is operated to change the direction of the magnetic field of the permanent magnet, making the magnetic lines of force close inside the chuck (without external magnetism), the magnetic force on the panel disappears, and the materials are released.  
- Characteristics: It does not require continuous power supply, is energy-saving and has high safety (it can still maintain magnetic force when power is off), but the magnetic force is fixed, and the adjustment flexibility is low.

 Summary
Whether it is the electromagnetic type or the permanent magnetic type, the core logic of the excavator's strong magnetic chuck is to achieve material grabbing through the attraction of the magnetic field to ferromagnetic substances. The only difference lies in the generation of the magnetic field (electric current or permanent magnet) and the control method (current on-off or mechanical switching). This design allows excavators to efficiently replace manual labor or traditional hooks in scenarios such as metal recycling, steel handling at construction sites, and waste cleaning, greatly improving work efficiency.

The strong magnetic sucker of an excavator works mainly based on the principles of electromagnetic induction or the magnetic properties of permanent magnets. It generates a strong magnetic field to attract ferromagnetic metal materials (such as steel, scrap iron, steel bars, etc.), enabling efficient material handling operations. The specific working process varies slightly depending on the type of chuck (electromagnetic or permanent magnetic), and the details are as follows: