As a company specializing in cast polyurethane (CPU) products, Shanghai Pepsen utilizes precise casting technology to manufacture high-quality polyurethane coated rollers suitable for industries such as logistics & warehousing, textile, plastic film, papermaking, and material handling. The following focuses on the casting process of polyurethane coated rollers.
Substrate Preparation for Roller Core
1. Clean Pretreatment
For both new metal roller cores and refurbished old ones, environmentally friendly solvents are used to remove oil stains, rust, and residual PU, ensuring the surface finish meets Ra ≤ 0.8μm. For old roller refurbishment, a combination of "mechanical stripping + chemical degumming" is adopted to fully remove the old layer without damaging the substrate.
2. Activation for bonding agent
Sandblasting is performed on roller surface , in order to creates a "mechanical anchoring effect," enabling chemcial bonding between the polyurethane layer and the substrate.
Casting Molding Polyurethane
1. Mold & Temperature
CNC-machined molds are preheated at 80-85℃ for 2 hours to guarantee uniform flow of the polyurethane material during casting.
2. Vulcanization Process
After casting at a constant temperature of 80-90℃, the roller undergoes a three-stage vulcanization: 40℃ for 2 hours (pre-curing) → 80℃ for 12 hours (main curing) → 100℃ for 6 hours (post-curing). This process ensures the polyurethane layer reaches over 95% cross-linking , significantly enhancing its tear resistance.
3. Precision Post-Processing
The cast rollers undergo 48 hours of natural aging to eliminate internal stress, followed by a full inspection to ensure consistent product quality.
Shanghai Pepsen’s Quality Assurance
Shanghai Pepsen has built a full-process quality control system. It has 10 inspectors who conduct inspections covering raw materials, first article, casting process, and finished products. Every polyurethane coated roller undergoes inspection, ensuring the company provides stable and reliable core components for industrial transmission.