Reasons and solutions of jaw crusher returning and not cutting

Let's first analyze the material return phenomenon of the jaw crusher:
Cause Analysis
1. The problem of the equipment itself
Jaw crusher parts are inconsistent with the dimensions of the drawings, such as the length and thickness of the jaw, the length of the bracket, the angle of the bracket, and the size of the frame cavity are not standard, resulting in inferior machinery. After long-term use, the angle between the two jaws is more than twice the friction angle, so that sufficient friction cannot appear between the material and the jaws to overcome the upward component of the crushing force, and the material is extruded under the influence of the vertical upward force. , Slide to the direction of the material inlet.
2. Unbalanced forces on crushed materials
Under the action of the upper and lower force of the movable jaw, the vertical force of the material to be broken in the crushing cavity is easily unbalanced, and under the action of the upward component of force, the phenomenon of material return is likely to occur.
3. The width of the discharge opening is too large
Many outsiders believe that the wider the discharge port of the jaw crusher, the better. In fact, the larger the width of the discharge port of the jaw crusher of the same specification, the easier it is to return material. During the crushing process, the material is in direct contact with the jaw plate, causing friction. The more severe the jaws are worn, the greater the possibility of material return.
4. The size of the material to be broken varies greatly
Generally speaking, the feed size of the jaw crusher is the same, so as to ensure uniform feeding, and when the size of the material to be broken is very different, it is easy to return to the phenomenon.
1. According to the material situation, use a crusher of appropriate specifications.
2. When the jaw plate is worn out, the material return phenomenon occurs, and the jaw plate should be repaired or replaced in time.
3. When the material size difference is too large, screen it. The coarse jaw crusher is pre-processed, and then the fine jaw crusher is used for finishing, which can meet the processing requirements of the material.
4. At the joint surface of the movable jaw and the movable jaw, a wedge-shaped backing plate is added to reduce the angle between the two jaws, so that the angle between the two jaws is less than twice the friction angle, and the phenomenon of material return is eliminated.
5. A protective plate can be welded above the inlet of the jaw crusher to prevent the material from flying out of the inlet to endanger the personal safety of the operator.
What is going on when the jaw crusher does not feed?
Cause Analysis
1. The material to be broken has high humidity
When the jaw crusher encounters materials with large surface moisture, or the crushed materials are mixed with mud, it is very easy to jam, causing the minerals to fail to come down, and the phenomenon that the ore is blocked in the cavity after being crushed and cannot be fed.
2. Too much feeding at one time or too fast feeding speed
During the operation of the equipment, if the feeding amount is too fast and uneven, it is very easy to cause too much material to accumulate in the lower cavity of the jaw crusher, block the discharge port, and then unload the material.
3. There are raw materials that cannot be broken such as iron blocks (or the hardness of the broken object is too large)
If the raw materials that cannot be crushed such as iron blocks are not picked out when the raw materials are added, it will cause certain damage to the jaw plate of the jaw crusher, thereby affecting the cutting.
4. Installation error
If the connection position of the motor is reversed, the main engine will turn on the reverse and the movable jaw will rotate clockwise, or the delta connection of the motor may be connected to the star connection.
5. Low voltage at work site
The voltage is too low to provide the power required for the normal operation of the main engine, resulting in too slow discharging or even no discharging.
1. Check from the source, pre-screen the materials that need to be crushed, and filter those materials that do not meet the crushing requirements, such as iron blocks.
2. Do the pre-screening, washing, and ore blending steps to control moisture before crushing, so as to ensure the dryness and purity of the material to be crushed (remove dust and dust). If there is still jamming and unloading during the crushing process, measures need to be taken to reduce the spindle speed and increase the discharge opening, but when adjusting the discharge opening, the adjustment angle should not be too flat.
3. Since the prerequisite requirements for the crushing of jaw crushers under different models and specifications (such as: inlet and outlet particle size, crushing capacity, etc.) are different, it is recommended that users know the selected model of jaw crusher in advance when purchasing equipment What are the basic requirements for materials and so on.
4. Strictly follow the operating instructions. The operators need to go through strict training before they can go to work after they are qualified.
5. Increase the working site voltage to adapt to the heavy load requirements of the host.
For more questions about the jaw crusher, please leave a message for consultation and discussion!
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