For rubber sealing strip production lines, there are two main types: single‑extrusion lines and composite‑extrusion lines. Regardless of the production method, the process begins with an extruder to form the profile, followed by a vulcanization step using vulcanization equipment to produce the final product. Some people ask whether these production lines meet environmental standards. During extrusion, the rubber extruder itself generates no pollution; only during vulcanization—when the product is cured in the vulcanization chamber—do small amounts of exhaust gases arise. By installing flue gas ducts to collect these emissions and routing them to a plasma‑based air purification system, we can readily satisfy our environmental requirements. When selecting an air‑purification system, it’s advisable to compare performance specifications based on the number of production lines operating in your facility. After the extruder shapes the product, a conveyor belt within the vulcanization chamber transports it to the opposite end of the curing tunnel. The vulcanization chamber is divided into three sections, and by equipping the interfaces and both ends with exhaust‑gas collection ports, we can fully comply with our environmental standards. In short, when rubber sealing strip production follows a standardized process, environmental impact can be effectively controlled.

1. Working Principle

Extrusion molding is a manufacturing process in which a plasticizable compound is continuously forced through a die under specific conditions, thereby producing a product with a defined cross-sectional shape.

As the rubber compound advances along the screw, mechanical and thermal effects cause changes in its viscosity and plasticity, transforming it into a viscous fluid. Based on the material’s behavior during extrusion, the working section of the screw is typically divided into three distinct zones—feeding, compression, and metering—each serving a specific function.

2. Cold-feed extrusion

Advantages: It saves on hot‑melt processing equipment, facilitates mechanization and automation, and, thanks to the main unit’s enhanced screw shear and plasticizing action, ensures uniform temperature and plasticity of the compound. It also improves the quality of extruded products, enhances surface finish, and produces semi‑finished extrudates with more stable and consistent dimensional tolerances. Furthermore, cold‑feed extrusion is less sensitive to pressure fluctuations and offers greater operational flexibility, while requiring lower capital and operating costs.

3. Equipment Features

Suitable for extruding rubber compounds (EPDM, natural rubber, nitrile rubber, butyl rubber, and reclaimed rubber), it is used in the production of composite sealing strips for architectural doors and windows, single‑extruded sealing strips, as well as various dense and foamed rubber products—such as strip‑shaped, bar‑shaped, tubular, and sheet‑like items—for applications in construction, electrical appliances, machinery, water conservancy, and other industries.

Cold-feed rubber sealing strip extruder: This is a type of equipment that uses cold rubber for production, with forced cold feeding as the standard feeding method. Cold-feed rubber extruders are characterized by high production efficiency and stable operation. Extruders are commonly used to manufacture products such as sealing strips and rubber hoses that can be produced via extrusion. An extruder is a rubber-processing machine employed to extrude tread compounds, inner tubes, rubber hoses, and various rubber profiles.

Hebei Shuangda Rubber & Plastics Machinery Co., Ltd. is a modern enterprise integrating research and development, manufacturing, and sales of complete sets of extrusion equipment for rubber, silicone, and plastics. The company’s main products include rubber extruders, rubber hose extrusion lines, three‑layer composite sealing strip extrusion lines, silicone sealing strip production lines, plastic sealing strip production lines, plastic profile extrusion lines, plastic pipe extrusion lines, elastomer extruders, and other extrusion equipment, as well as production machinery for engineering seals, automotive seals, wire and cable applications, air‑conditioning hoses, braided hoses, automotive hoses, waterstop strips, and related products.