As the core equipment of a wood-plastic composite (WPC) production line, the screw operation of the wood-plastic extruder directly affects production stability. If abnormal noise suddenly occurs during operation, based on the equipment design features of Qingdao Yongte Plastic Machinery (such as precision forged core components and intelligent control systems), the Yongte engineering team provides the following troubleshooting solutions:
1. Excessive Moisture Content or Impurities in the Material: The noise is often a "rustling" or "jamming" sound, accompanied by uneven plasticization and fluctuations in output. Check the moisture content of raw materials such as wood flour and plastic particles (the standard moisture content of wood-plastic raw materials should be ≤8%), and observe whether there are impurities such as sand, gravel, and metal fragments at the feed inlet. 1. Re-dry damp raw materials to ensure the moisture content meets the standard; clean the feed hopper and silo, check if the raw material screening device is malfunctioning, and install a magnetic iron removal device if necessary; if hard impurities have been mixed in, immediately stop the machine, disassemble the screw head, and clean the foreign objects (refer to Yongte equipment's "humanized disassembly design" to avoid violent operation).
2. Material formula or particle size mismatch: Noise accompanied by screw speed fluctuations and abnormally high barrel temperature. Confirm whether the raw material formula has been changed (such as wood flour ratio, lubricant addition amount), and whether the particle size is uniform (excessively large particles can easily cause screw conveying jams). Restore the original formula parameters, adjust the lubricant ratio, and ensure that the material flowability is compatible with the screw pitch design; perform secondary crushing and screening of the raw materials to ensure uniform particle size (to meet the plasticizing requirements of Yongte's high-speed screw system).
1. Excessive wear clearance between the screw and barrel: Continuous "humming" abnormal noise, accompanied by decreased output and rough product surface. After stopping the machine, manually rotate the screw to check for any noticeable shaking; check the discharge section for uneven wear marks. Repair or replace the screw/barrel using original parts (Yongte equipment's core components use high-strength wear-resistant materials, resulting in a longer wear cycle under normal use; sudden excessive clearance is mostly caused by foreign object impact); if stopping the machine is not possible temporarily, appropriately reduce the screw speed to reduce impact noise.
2. Screw bending or screw edge damage: Periodic "impact sound," the noise intensifies with increasing speed, possibly accompanied by localized overheating of the barrel. Observe the screw's running trajectory through the equipment's observation window, or check the screw's straightness and screw edge integrity after stopping and disassembling. Do not continue operation to avoid damaging the barrel; please contact Yongte technicians immediately for screw correction or replacement (original screws using Yongte's "precision forging process" ensure accurate matching with the barrel).
1. Motor or reducer failure: Noise originates from the transmission box at the rear of the equipment, often described as "gear meshing noise" or "bearing rumbling." 1. Check if the motor speed is stable, and the level and color of the reducer lubricating oil (black or insufficient oil can easily lead to gear wear); touch the motor casing to determine if it is overheating. Add or replace the reducer-specific lubricating oil (refer to the recommended model in the Yongte equipment after-sales manual);If the motor bearing is damaged, replace it with an original bearing (Yongte equipment is equipped with a high-efficiency permanent magnet servo motor, requiring matching specifications); use the equipment's intelligent control system to monitor the motor current and avoid overload operation.
2. Loose coupling or coaxiality deviation: A "clunking" impact sound occurs during startup or speed change, and the noise varies with the load. Check if the coupling bolts are loose, and use a dial indicator to measure the coaxiality of the motor and reducer. Tighten the coupling bolts and recalibrate the coaxiality (error ≤ 0.02mm); if the coupling rubber gasket is aged, replace it with an original part (Yongte equipment parts are highly versatile and can be quickly adapted).
1. Low temperature in the barrel heating section: Noise accompanies insufficient material plasticization, and the screw conveying resistance increases ("muffled sound"). 1. Check if the temperature displayed on the intelligent temperature control system matches the actual measured temperature, and whether the heating coil is damaged. Reset the heating parameters according to the wood-plastic processing temperature curve recommended by Yongte Equipment (different materials, such as PE/WPC and PVC/WPC, have different temperatures); replace damaged heating coils or temperature sensors to ensure uniform temperature (Yongte Equipment's "zonal temperature control design" can precisely adjust the temperature of each section).
2. Cooling system failure: Overheating at the screw tail or middle section of the barrel, accompanied by "abnormal noise due to thermal expansion". Check if the cooling fan is working properly. Check if the screw center cooling system is unobstructed to prevent the screw and barrel from jamming due to thermal expansion. Replace the faulty cooling fan.
1. Loose equipment anchor bolts: Overall equipment vibration accompanied by "resonance noise", the noise frequency is synchronized with the screw speed. Check if the anchor bolts at the bottom of the equipment are loose, and whether the frame is deformed. Tighten the anchor bolts, adjust the frame level (refer to the leveling requirements in the Yongte Equipment Installation Manual), and add vibration damping pads if necessary to reduce resonance. 2. Loose connection at the feed inlet or mold: Localized "vibration and abnormal noise," concentrated at the feed inlet or mold flange connection. Check if the feed hopper fixing bolts and mold flange bolts are loose. Tighten each bolt at the connection points one by one, ensuring the gasket is properly installed (to prevent material leakage and reduce vibration noise).
Immediately Reduce Speed and Stop the Machine: Upon detecting abnormal noise, first reduce the screw speed to the minimum and observe if the noise subsides. If the noise persists or worsens, immediately disconnect the power and stop the machine to prevent further damage to the screw and barrel.
Initial Noise Source Location: Determine whether the noise originates from the front end (screw/barrel), middle end (feed inlet), or rear end (transmission system) through hearing, sight, and touch (avoid burns).
Basic Troubleshooting: Prioritize checking easily diagnosable items such as material condition, connecting bolts, and temperature parameters to avoid blind disassembly.
Professional Support: If the problem persists after troubleshooting (e.g., bent screw, reducer malfunction), immediately contact the Qingdao Yongte after-sales team. Provide noise video and operating parameters (speed, temperature, material type). Leveraging the "Three-Year Warranty + Lifetime Support" service, obtain remote guidance or on-site repair (Yongte overseas customers can enjoy localized after-sales response).
