Cast Iron Pulley

The manufacturing process of Jiangsu Shengrong’s cast iron pulley follows strict industrial standards, covering 8 core stages to ensure the performance and durability of the product. Below is the detailed workmanship flow:

1. Design & Mold Preparation for Cast Iron Pulley
Drawing Design: Based on application conditions (e.g., transmission power, speed, installation size) and requirements, design the size, groove type (e.g., V-groove, multi-wedge groove), and structure of the cast iron pulley. This ensures the final product matches the actual transmission needs of equipment.
Mold Manufacturing: Produce wooden molds, metal molds, or foam molds (determined by casting methods) for sand casting of the cast iron pulley, or prepare metal molds for die casting—laying the foundation for precise casting of the pulley.

2. Casting Process for Cast Iron Pulley
(1) Melting
Raw Material Preparation: Select gray cast iron (HT150, HT200, etc.) or ductile iron (QT500-7, etc.) as the base material for the cast iron pulley, and proportionally add scrap steel, pig iron, and recycled materials to optimize material performance.
Molten Iron Melting: Melt the prepared raw materials in a cupola or electric furnace, and control the temperature at approximately 1400~1500℃ to ensure full melting and fluidity.
Composition Adjustment: Add elements (e.g., carbon, silicon, manganese) to adjust the chemical composition of molten iron, enhancing the strength and wear resistance of the final cast iron pulley.
(2) Pouring
Sand Casting (Mainstream Method):
Mold Making: Create a cavity in a sand box (using wet sand or resin sand) with wooden or other molds, which is tailored to the shape of the cast iron pulley.
Mold Assembly: Align the upper and lower sand boxes to form a complete mold cavity for the cast iron pulley.
Pouring Operation: Pour molten iron into the cavity at a controlled flow rate to avoid air holes or incomplete filling in the cast iron pulley.
Other Methods: Lost foam casting is used for small-batch cast iron pulley production, while metal mold casting is adopted for large-batch manufacturing to improve efficiency.
(3) Cooling & Cleaning
After the molten iron in the mold cools and solidifies, unpack the mold, take out the rough cast iron pulley, and remove risers, flash, and burrs. Then, perform sandblasting or shot blasting to clean the surface sand of the pulley, ensuring a smooth base for subsequent processing.

3. Machining of Cast Iron Pulley
Turning: Use a lathe to machine the inner hole, end face, and outer circle of the cast iron pulley’s hub, ensuring precise dimensions and concentricity—critical for stable transmission.
Belt Groove Processing (for Cast Iron Belt Pulley): For cast iron belt pulley (a common type), use milling machines or CNC lathes to process belt grooves (e.g., V-grooves, multi-grooves). The groove angle and depth must meet industry standards to ensure tight fit with belts during transmission.
Drilling: Machine mounting holes or keyways on the cast iron pulley to ensure accurate matching with the transmission shaft, guaranteeing smooth power transfer.

4. Heat Treatment (Optional for Cast Iron Pulley)
Annealing: For ductile iron cast iron pulley, annealing is performed to eliminate casting stress and improve machinability, reducing the risk of deformation during use.
Surface Quenching: For cast iron pulley requiring high wear resistance (e.g., those used in heavy-duty transmission), quench the groove surface to enhance hardness and extend service life.

5. Dynamic Balancing Test (Key Step for High-Speed Cast Iron Pulley)
Cast iron pulley used in high-speed transmission (e.g., for industrial machinery) must undergo dynamic balancing tests. By adding counterweights, removing material, or adjusting weight distribution, imbalance is eliminated—avoiding vibration, noise, or premature wear of the cast iron pulley during operation.

6. Surface Treatment & Rust Prevention for Cast Iron Pulley Wheel
To improve the corrosion resistance of the cast iron pulley wheel (especially for outdoor or humid environments):
Spraying/Plating: Apply anti-rust paint, galvanizing, or phosphating to the surface of the cast iron pulley wheel.
Oiling: For short-term storage, coat the cast iron pulley wheel with anti-rust oil to prevent rusting.

7. Quality Inspection of Cast Iron Pulley
Dimensional Inspection: Use calipers, coordinate measuring machines, etc., to check key dimensions (e.g., inner hole diameter, groove depth) of the cast iron pulley, ensuring compliance with design standards.
Appearance Inspection: Check the cast iron pulley for defects such as cracks, pores, or sand holes—rejecting unqualified products to ensure quality.

8. Packaging & Warehousing of Cast Iron Pulley
Package the qualified cast iron pulley according to customer requirements (e.g., wooden boxes, pallets, or moisture-proof films), mark specifications and models clearly, and store them in the warehouse for shipment—ensuring the product reaches customers in good condition.