Material carryback is a persistent problem in conveyor systems. It occurs when small amounts of material stick to the conveyor belt and are carried past the discharge point. This issue leads to unnecessary material loss, increased maintenance costs, and potential damage to the conveyor. Here’s how to address and prevent carryback effectively.
- Install Primary Belt Cleaners
Primary cleaners are positioned at the head pulley to remove the bulk of material adhering to the belt. These cleaners are usually made of durable materials such as urethane or tungsten carbide and are designed to scrape off residual material without damaging the belt.
- Add Secondary Belt Cleaners
While primary cleaners remove most of the carryback, some fine material may remain. Secondary cleaners, located further down the belt, address this issue by providing an additional cleaning stage. Combined, primary and secondary cleaners significantly reduce carryback.
- Use Specialty Belt Cleaners
For specific materials like sticky or moist substances, specialty cleaners are often more effective. These may include rotary brush cleaners or water-based cleaning systems that remove stubborn residues.
- Regularly Inspect and Maintain Cleaners
Even the best belt cleaners require regular maintenance. Worn or misaligned cleaners become ineffective over time, leading to increased carryback. Inspect cleaning systems frequently and replace worn blades or brushes promptly.
- Optimize Belt Surface
Carryback often occurs when materials stick to the belt due to surface properties. Coating the belt with anti-stick materials or using belts with a low-friction surface can reduce material adherence.
- Install Belt Washing Systems
In applications where materials are particularly sticky, a belt washing system may be necessary. These systems use water and cleaning agents to remove carryback before it becomes a problem.
- Monitor Belt Tension
Incorrect belt tension can lead to uneven material discharge and contribute to carryback. Ensure the belt tension is adjusted to the manufacturer’s specifications for optimal performance.
- Use Proper Material Discharge Systems
Properly designed discharge systems, including chutes and vibratory feeders, ensure that materials leave the belt cleanly and minimize carryback risks.
- Minimize Material Build-Up
Material build-up on pulleys, idlers, or return belts exacerbates carryback issues. Use scrapers, plows, and other tools to keep these components free of material.
- Train Staff
Operators and maintenance personnel should be trained to identify and address carryback problems. Properly trained staff can spot early warning signs and take corrective action before carryback causes significant issues.
By implementing these measures, you can effectively reduce or eliminate material carryback, improving conveyor efficiency and reducing maintenance costs.
