Locating the Blockage
Work along the material conveying path, starting from the storage hopper, and inspect each section in sequence—including conveying pipelines, elbows, valves, metering devices, and material distributors. Check for visible signs of material buildup on the external surface of pipes, listen for abnormal material flow sounds inside the pipes, or use the system's built-in blockage detection device (if available) to pinpoint the location of the blockage.
For concealed or hard-to-inspect areas, tools such as borescopes can be used for assistance.
Analyzing the Causes of Blockage
Material Factors
Check material properties such as moisture content, particle size, shape, and flowability.
High-moisture materials are prone to clumping and causing blockages.
Non-uniform particle sizes or irregular shapes may cause jamming in narrow sections.
Materials with poor flowability are more likely to accumulate and clog.
Equipment Factors
Inspect conveying pipelines for wear, deformation, or internal surface roughness, which can cause material buildup on pipe walls.
Check if the bend radius of elbows is too small, as this can increase flow resistance.
Ensure valves open and close properly—improper closure or incomplete opening may hinder material flow.
Verify the accuracy of metering devices; significant measurement errors may lead to uneven material supply and blockages.
Confirm that material distributors are functioning correctly, as uneven distribution can also cause blockages.
Operational Factors
Review operational procedures to determine if the feeding speed exceeds the system’s conveying capacity.
Check whether conveying parameters (e.g., speed, air pressure) were suddenly altered during operation, disrupting material flow stability.
Clearing the Blockage
Manual Clearing
For minor blockages in easily accessible areas (e.g., near the hopper outlet or the start of the pipeline), shut down the relevant equipment, open the inspection port, and carefully remove the clogged material using specialized tools (e.g., shovels, brooms). Avoid damaging the internal pipe walls.
Reverse Air Blowing
For longer pipelines or hard-to-reach blockages, use the system’s built-in reverse blowing device (if available) to introduce reverse airflow, loosening and removing the blockage.
If no such device is installed, connect a temporary compressed air line for reverse blowing. Ensure air pressure is controlled to avoid damaging the pipeline or equipment.
Disassembly for Clearing
If the blockage is severe and cannot be resolved manually or by reverse blowing, disassemble sections of the pipeline, valves, or other components to thoroughly remove the clogged material. Label parts during disassembly to ensure correct reassembly.
Preventive Measures
Optimize Material Handling
Dry materials with high moisture content.
Screen or crush materials with uneven particle sizes to meet conveying requirements.
Add appropriate lubricants or flow improvers to enhance material flowability.
Maintain and Upgrade Equipment
Regularly inspect and maintain conveying pipelines, promptly repairing worn or deformed sections to ensure smooth inner walls.
Replace elbows with excessively small bend radii with appropriately sized ones.
Regularly inspect and calibrate metering devices to ensure accuracy.
Inspect and maintain valves and material distributors to ensure proper operation.
Standardize Operating Procedures
Establish and adhere to appropriate feeding speeds, maintaining stable operation.
Avoid abrupt changes to conveying parameters during operation. If adjustments are necessary, implement them gradually while closely monitoring material flow conditions.
