What are the steps in the production process of rubber rollers?

**Raw Material Preparation**
1. **Rubber Selection**: Select suitable rubber varieties, such as natural rubber and synthetic rubber, according to the usage requirements of the rubber roller. Consider its physical properties, chemical stability, and abrasion resistance.

2. **Compound Agent Preparation**: Prepare various compounding agents such as vulcanizing agents, accelerators, antioxidants, and fillers. These compounding agents improve the properties of the rubber; for example, vulcanizing agents cross-link and cure the rubber, while fillers enhance the hardness and abrasion resistance of the rubber.

**Mixing**
1. Plasticize the rubber on a rubber mixing mill to reduce its molecular weight and improve its plasticity, facilitating subsequent processing.

2. Accurately weigh various compounding agents according to the formula and add them sequentially to the rubber mixing mill to mix with the rubber. During the mixing process, the rubber and compounding agents are thoroughly and evenly mixed to form a compound with good processing performance and overall properties.

**Molding**
1. **Mandrel Treatment**: Clean and grind the mandrel of the rubber roller to ensure that the mandrel surface is smooth and free of impurities, ensuring good bonding with the rubber layer.

2. **Coating with Release Agent**: A release agent is coated onto the mandrel surface to prevent the rubber compound from sticking to the mandrel.

3. **Rubber Coating**: The compounded rubber is coated onto the mandrel using processes such as extrusion or calendering to form a rubber layer of a certain thickness. Extrusion allows for continuous production and is highly efficient; calendering produces a rubber layer of uniform thickness.

Vulcanization
1. The molded rubber roller is placed in a vulcanizing tank or vulcanizing machine.

2. Under specific temperature, pressure, and time conditions, the rubber in the rubber layer undergoes a cross-linking reaction, transforming from a plastic state into a highly elastic vulcanized rubber. The vulcanization temperature is generally around 140℃-180℃, and the vulcanization time depends on the size of the rubber roller and the formulation, typically several tens of minutes.

Post-Processing
1. **Surface Treatment**: The surface of the vulcanized rubber roller is ground and polished to achieve the required surface finish and improve the roller's performance.

2. **Dimensional Machining:** Based on actual usage requirements, the rubber rollers undergo machining such as turning and grinding to ensure dimensional accuracy in areas such as outer diameter, length, and cylindricity.

3. **Quality Inspection:** Comprehensive inspection of the rubber rollers' appearance, dimensions, hardness, and physical properties is conducted to ensure product quality meets standards and customer requirements.