It is important to follow correct procedures when changing the wear parts of a jaw crusher to avoid any potential risks. Different types of jaw plates will require different methods for replacement.
For a two-piece jaw die rotation and replacement, the worn out jaw dies should be removed from the bottom of the crushing chamber. Work-hardened upper jaw dies should then be installed at the bottom of the crushing chamber, followed by installing new jaw dies at the top of the chamber.
For a one-piece jaw die rotation and replacement, the single-piece jaw dies should be rotated after 30% of the tooth profile has worn, and then rotated again when the tooth profile at the bottom of the jaw die is completely worn.
There are 13 steps to follow when changing jaw plates, which include preparing the necessary tools such as a 600 live-mouth wrench, wire rope, hand hammer, mast, sledgehammer, electric welding, and crane.
To begin, the feeding and operation of the crusher should be stopped, and insulated gloves should be worn to prevent electric shock from wet hands. The screw of the old jaw plate should be removed, and the side plate should be loosened and lifted with an overhead crane.
The clamps should be removed, and the stationary plate clamps should be slowly taken off and placed nearby. The welding hoisting ring should then be welded to both the moving plate and the fixed plate, ensuring a firm solder to prevent bruises during lifting.
The jaw plate should be lifted, and the crane should be started to lift the moving plate and the fixed plate and transport them to the waste material storage area. It is important to monitor the crane during this process to avoid any injuries, and the wire rope should be strong.
The new jaw plate should then be lifted, and the crane should hang the moving plate and the fixed plate separately. The clamps should be installed, placed in their proper position, and tightened with screws.
Finally, the stationary plate screws should be tightened, and the side plates should be installed. The gap of the discharge port should be adjusted before starting the jaw crusher and vibrating the mine for trial operation.