Barrel Liners

Barrel liners are critical wear components installed inside the barrel assembly of plastic processing machinery such as extruders and injection molding machines. They provide a durable, smooth inner surface that guides and contains the plastic material as it's conveyed, melted, and pressurized. Liners protect the main barrel body from abrasion, corrosion, and thermal degradation while maintaining precise dimensional tolerances for consistent processing. These liners are designed as sacrificial wear surfaces, directly contacting the plastic material during processing. They withstand continuous friction from the rotating screw, high pressure (up to 300+ bar), and elevated temperatures (typically 150-350°C). The liner's smooth bore ensures consistent material flow while its wear-resistant properties maintain dimensional stability over thousands of operating hours. When worn beyond tolerance, liners can be replaced without replacing the entire barrel assembly. Available materials include bimetallic alloys (stellite/cobalt-based), nitrided steel, tool steel with hard chrome plating, and ceramic-metal composites. Key parameters include inner diameter (20–200 mm), length (100–2000 mm), wall thickness (5–25 mm), hardness (58–62 HRC per ASTM E18), surface roughness (Ra 0.2–0.4 μm per ISO 4287), tolerance grade (IT6–IT7 per ISO 286), operating temperature (200–400°C), operating pressure (50–150 MPa), material grade (38CrMoAlA per GB/T 3077), nitriding depth (0.3–0.6 mm per GB/T 11354), and weight (5–150 kg). These values are reference ranges; actual specifications must be confirmed with the manufacturer for the specific model and application. Standards listed are for verification purposes and do not imply certification. Always consult the legal manufacturer or supplier to verify model-specific values and standards.

Barrel liners function as sacrificial wear surfaces that directly contact the plastic material during processing. They withstand continuous friction from the rotating screw, high pressure (up to 300+ bar), and elevated temperatures (typically 150-350°C). The liner's smooth bore ensures consistent material flow while its wear-resistant properties maintain dimensional stability over thousands of operating hours. When worn beyond tolerance, liners can be replaced without replacing the entire barrel assembly.