What are the steps to replace a broken wall?

The crushing wall is the main wear-resistant component that directly contacts the material in a cone crusher and needs to be replaced after a certain period of use. The correct replacement steps not only affect whether the new broken wall can be reliably fixed, but also directly affect the stability and safety of the equipment's subsequent operation. The following introduces the complete replacement steps of the broken wall in the order of operation, covering preparation work, disassembly, installation, fastening, and commissioning.

1、 Preparation before replacement

Before starting to replace the broken wall, the following preparations need to be made.

1. Cut off the power and hang a warning sign: First, completely cut off the power of the cone crusher, turn off the main switch, and hang a warning sign in a prominent position that reads "under maintenance, no closing" to prevent other personnel from starting the equipment without knowledge. The lubrication pump also needs to undergo pressure relief treatment.

2. Prepare all necessary tools and materials: Prepare in advance the new crushing wall, cutting ring that needs to be replaced (note that a new cutting ring should be installed every time the dynamic cone lining plate is replaced, and this part cannot be reused), conical feeding tray (also known as feeding cone hopper, which should be replaced together with each replacement of the dynamic cone lining plate), casting materials such as zinc alloy or epoxy resin, pressure sleeves, pressure caps, sealing rings, pressure covers, cone heads, as well as the required tools (such as gas welding equipment, lifting equipment, calipers, torque wrenches, jacks, etc.). In addition, asbestos, clay, lubricating oil, and butter should be prepared.

3. Preheating: To avoid accidental injury to operators caused by splashing water vapor during the pouring process, the lining plate, body or adjustment sleeve should be uniformly preheated to about 60-80 ℃. Preheating can also remove surface moisture to a certain extent.

2、 Dismantle the old broken wall

1. Lift out the spindle components: The broken wall can be replaced directly on site. Firstly, lift out the main shaft components of the crusher and place them flat on a sturdy support platform. During this process, attention should be paid to protecting the sphere and cone from damage.

2. Blocking oil holes: Use a clean cloth or temporary sealing material to block all oil holes to prevent dust, impurities, and metal shavings from falling into the oil system. This is more important because blockages or impurities entering the oil circuit may cause malfunctions such as poor oil supply during subsequent equipment operation.

3. Disassemble the upper components in sequence: Remove the distribution plate, locking washer, locking nut (or compression nut), melting washer, and other fixed parts located above the crushing wall in sequence. It is recommended to operate and store the removed parts according to the equipment manual when dismantling these fixed components.

4. Install lifting lugs and lift out the broken wall: Weld two lifting lugs at 180 ° apart on the old broken wall (accurate relative position of the two lifting lugs helps with smooth lifting), and use lifting equipment to lift out the old broken wall smoothly. If the old lining plate is difficult to remove, it can be disassembled and removed by gas welding cutting.

3、 Cleaning and Inspection

After dismantling the old broken wall, it is necessary to inspect the mating surfaces and related components.

1. Cleaning the mating surface: Thoroughly remove any remaining old zinc alloy, rust, oil stains, and other impurities on the body, exposing the metallic color of the body surface to ensure that the newly cast filler can bond firmly.

2. Check the wear of relevant components: While replacing the broken wall, check whether there are scratches or burrs on the mating surface of the moving cone, and if so, remove them. It is also necessary to check the wear of the fixed cone, adjustment ring, locking thread, counterweight and counterweight guard plate. If the wear is severe, new parts should be replaced together to reduce the time for secondary replacement and disassembly.

3. Apply lubricating oil: Apply a thin layer of lubricating oil on the inner surface of the lining plate and the body contact surface. This not only prevents moisture, but also avoids adhesion between the subsequently poured zinc alloy and these surfaces. Note that for certain models of cone crushers, the seat area should not be lubricated as maintaining friction helps to enhance performance.

4、 Install a new broken wall

1. Lifting in place: Weld two lifting lugs at 180 ° apart on the newly broken wall, and use lifting equipment to place them steadily on the body. Adjust the position of the broken wall to ensure it is aligned with the body - misalignment of the liner center can cause collisions during subsequent operation, resulting in uneven wear of the liner.

2. Install the compression nut: After aligning the new broken wall, first install the compression nut to preliminarily position the broken wall before pouring.

3. Sealing joints: Use asbestos and clay to seal the gaps at the joints of the lining board to prevent zinc alloy from leaking from the gaps during subsequent casting.

4. Casting zinc alloy: Inject zinc alloy into the gap between the crushing wall and the body using specialized tools. During the pouring process, attention should be paid to controlling the pouring speed and temperature to ensure that the filling material fills the gaps tightly and avoids the formation of bubbles or voids. If resin fillers are used instead of zinc alloys, they should be operated according to the instructions provided by the filler supplier. After the zinc alloy solidifies, carefully clean the excess alloy adhering to the broken wall end face and other surfaces.

5. Install other components: sequentially install the pressure sleeve, pressure cap, sealing ring, pressure cover, and conical head in place, and firmly lock the pressure cap. During the tightening process, a torque wrench should be used to operate according to the force value given in the equipment manual - too little pre tightening force can cause the broken wall to loosen, while too much pre tightening force can generate excessive additional stress inside the broken wall, which poses a risk of rupture.

5、 Inspection after installation completion

1. Check the fastening condition: Newly installed or replaced broken walls should be stopped for 6 to 8 hours after the equipment is put into operation to check the fastening condition. If looseness is found, it should be tightened immediately. For the bowl wall fixed with U-screws, the U-screws should also be checked and tightened again at the same time after installation.

2. Empty machine test run: After completing all installation and fastening operations, an empty machine test run should be conducted to observe whether the equipment runs smoothly and whether there are any abnormal noises. After running the machine empty for a period of time and confirming that all indicators are normal, materials can be added to start normal production operations.

6、 Synchronous consideration on the replacement of the rolling mill bowl wall

The wear progress of the crushing wall and the rolling bowl wall, which work together in the crushing chamber, is usually correlated. In actual production, if the rolling mill wall is also approaching the replacement cycle, it is recommended to replace it at the same time as the crushing wall, so that the new pair of lining plates can enter the running in period synchronously. The main steps for replacing the bowl wall are as follows: first, unscrew the adjustment screw sleeve installed on the upper frame counterclockwise, remove the upper chamber hopper assembly, and lift the adjustment screw sleeve with lifting equipment; Remove and adjust the screw sleeve support plate bolts, then remove the old rolling bowl wall for replacement; Clean the outer surface during assembly, apply butter to the surface of the adjusting screw thread, and then reinstall and fix it in reverse order. The rolling bowl wall is fixed on the adjustment ring with U-shaped screws, and zinc alloy is injected between the two to make it tightly bonded