Extruder screw wear

During the extrusion '2079851475616104457 production process, the product exhibits the quality defect of "Extruder screw wear". Specifically manifested as unstable extrusion caused by wear of the screw and barrel. This defect is relatively common when processing materials such as HDPE, PP, PVC, and PC, and its occurrence conditions are usually related to unreasonable settings of melt temperature, extrusion speed, blowing air pressure, and mold temperature. When the Extruder screw wear situation is severe, it will cause a series of chain-reaction quality defects in the product in terms of appearance, dimensional accuracy, mechanical properties, etc., which not only reduces the usability and safety of the product, but also directly increases the scrap rate and production cost. Therefore, this problem requires systematic diagnosis and optimization from multiple dimensions, including material selection, the condition of the extruder, die head, die, mold clamping mechanism, and blowing system, as well as melt temperature, extrusion speed, blowing air pressure, and mold temperature.

1. Wear from long-term use. Mechanical wear and loosening during long-term equipment operation will cause clearance changes, accuracy degradation, and unstable operation, thereby triggering various process and quality problems. Establishing a regular inspection and preventive maintenance system for equipment operating conditions, and promptly repairing or replacing worn parts, is a necessary measure to maintain equipment accuracy and process stability. 2. The raw material contains abrasive fillers such as glass fiber. The selection and handling of materials is the foundation of molding quality. The intrinsic characteristics of the resin, such as molecular weight, molecular weight distribution, and melt index, determine its processing window and final performance. Factors such as excessive moisture content of the raw material, mixing in of impurities, and improper proportion of regrind will all trigger various defects during processing. In addition, insufficient overall coordination between parison wall thickness control and parison temperature uniformity is also a factor that cannot be ignored; there are complex interactions and coupling relationships among the various process parameters, and the deviation of any single parameter may aggravate the degree of Extruder screw wear through chain effects. In terms of equipment maintenance, inadequate regular overhaul and accuracy confirmation of the extruder, die head, die, mold clamping mechanism, and blowing system cause the actual operating parameters of the equipment to deviate from the process requirements, which can also become a potential inducement of the Extruder screw wear problem.

1. Regularly measure the screw clearance. Before implementing this measure, its feasibility and expected effect should be fully evaluated, and the details of the plan should be communicated and confirmed with relevant technical personnel; during implementation, changes in key quality indicators should be closely monitored, and the adjustment effect should be recorded and fed back in a timely manner to form reusable process experience. 2. Replace the worn screw or barrel. When replacing parts, spare parts of the same or higher specification from the original manufacturer should be selected to ensure that the installation accuracy and fit tolerances meet the technical requirements of the equipment. After replacement, the relevant parameters need to be recalibrated and a trial run performed to verify the effect; normal production can only be resumed after confirming that the expectations are met. It is recommended to establish a spare parts life cycle management ledger. 3. Use wear-resistant screw material. Before introducing new tools, new materials, or new methods, a full applicability assessment and small-batch verification should be carried out. It is recommended to first conduct offline tests or simulation analysis outside of production conditions, and introduce them into the formal production line only after confirming effectiveness and safety. Keep change management records to facilitate subsequent traceability and experience accumulation. In terms of material management, incoming inspection of raw materials and in-process inspection of work-in-progress should be strengthened, and the key performance indicators of HDPE, PP, PVC, and PC should be strictly controlled to ensure the stability of molding quality from the source.

In summary, the causes of the "Extruder screw wear" problem can be attributed to the combined action of multiple factors such as wear from long-term use and the raw material contains abrasive fillers such as glass fiber. Solving this problem requires starting from aspects such as regularly measure the screw clearance and replace the worn screw or barrel, and adopting systematic governance measures. In actual production, it is recommended to establish a prevention and rapid response mechanism for this problem, achieving stable production and continuous improvement through parison wall thickness control and parison temperature uniformity.