2. It is strictly forbidden to use cast iron or cast steel shackles. The buckle body can be forged with killed steel, and the shaft pin can be machined after forging from bar material.
3. The shackle should not be drilled or welded to repair. After the buckle body and the shaft pin are permanently deformed, no repairs are allowed.
4. When in use, check the buckle body and the bolt, and avoid serious wear, deformation and fatigue cracks.
5. When in use, the horizontal spacing must not be subjected to tension, and the shaft pin must be inserted with a safety pin.
6. After the shaft pin is assembled correctly, the width of the buckle body must not be significantly reduced, and the threaded connection is good.
7. The use of shackles shall not exceed the specified safe load.