How Can Quality and Longevity of Carbon Steel Conveyor Idlers Be Optimized?

The main problem with the use of carbon steel conveyor idlers is related to their operation. Issues in the operation of carbon steel conveyor idlers include a lack of flexibility in rotation, severe cases of non-rotation, which can change the rolling resistance coefficient to sliding, increasing it by approximately 10 times. This results in increased operational resistance, higher power consumption, and reduced conveying efficiency. Additionally, the inflexible rotation of carbon steel conveyor idlers leads to increased wear on both the conveyor idlers and the conveyor belt, reducing their service life. The decreased service life of carbon steel conveyor idlers necessitates frequent replacement, leading to a shortage of spare parts and increased maintenance work, which ultimately raises the transportation cost of coal.

Quality analysis and process formulation for carbon steel conveyor idlers: Several factors affect the flexibility of the operation and service life of carbon steel conveyor idlers. These factors include the structure of the carbon steel conveyor idlers, manufacturing quality, sealing and lubrication, and maintenance. The structure of carbon steel conveyor idlers mainly consists of pipe components, bearing seats, bearings, seals, lubricating grease, and shafts. The impact of these main components on the quality of carbon steel conveyor idlers is analyzed as follows:

1. Pipe components: The manufacturing quality of the pipe components is a crucial factor affecting the quality of carbon steel conveyor idlers. The roundness and axial alignment of the pipe components directly affect radial runout and rotational resistance, ultimately affecting the service life of carbon steel conveyor idlers. To improve the quality of carbon steel conveyor idlers, high-frequency welded pipes of good quality are used, and a steel pipe double-head processing machine is used to ensure the size and precision of the pipe ends. This prevents quality issues due to off-center pipe stops.

2. Bearing seats: DTII-type carbon steel conveyor idlers use stamped bearing seats. Using 3mm thick steel plate-stamped bearing seats has been proven to provide strong steel and ensure the assembly precision and flexibility of carbon steel conveyor idlers. The precision of the bearing seats directly affects the quality of carbon steel conveyor idlers. To ensure the size and coaxiality of the inner hole after stamping, high-quality materials and mold materials are used to design fixtures. The bearing seats are welded to the pipe body using CO2 gas protection welding, reducing rotational resistance, and radial runout.

3. Bearings: The service life of carbon steel conveyor idlers primarily depends on the performance of the bearings and seals. Bearings have a significant impact on both the service life and rotational resistance of carbon steel conveyor idlers. The main reasons for bearing failure are the entry of coal dust or slurry, grease loss, external moisture or humidity causing rust, poor-quality bearings, and assembly issues. To address these problems, 305KA bearings with larger clearances are used, resulting in a significantly longer service life and lower rotational resistance.

4. Lubricating grease: Commonly used lubricating greases for carbon steel conveyor idlers in underground coal mines include calcium-based and mining lithium-based greases. Calcium-based grease has good water resistance but tends to solidify at high temperatures, change color, and become unusable over time, affecting bearing service life. Mining lithium-based grease, in addition to retaining the main advantages of calcium-based grease, has strong water resistance and mechanical stability, making it suitable for harsh working environments with coal dust and water. Using lithium-based grease improves the lubrication of carbon steel conveyor idlers bearings and is necessary to extend their service life.

5. Shafts: The machining quality of the shafts is another important factor affecting the quality of carbon steel conveyor idlers. The roundness of the shafts directly affects radial runout and rotational resistance, influencing the operational life of carbon steel conveyor idlers. To address this, a one-pass machining and cutting method using top pins on both ends of the shaft is employed, ensuring the required size and precision of the shafts and avoiding quality issues due to shaft eccentricity.