1、 Daily maintenance (daily/shift)

1. Cleaning and Inspection
   • Cleaning of the cutting chamberAfter each shift, use specialized tools to clean the remaining plastic particles and scale in the cutting room to prevent blockage of the cutterhead or cooling water channel.
   • Tool inspectionVisually inspect the cutting edge for wear, chipping, or carbon buildup. If the edge becomes dull, it should be promptly ground or replaced (it is recommended to check every 8-12 hours).
   • Cooling system inspectionConfirm that the cooling water flow rate is normal (usually ≥ 5L/min), and the water temperature is controlled at 20-40 ℃ to avoid plastic particle adhesion caused by high water temperature.
   • Inspection of transmission componentsCheck the tension of the belt/chain to ensure there is no looseness or abnormal wear; Manually rotate the spindle and confirm that it rotates smoothly without any jamming.
2. Lubrication and maintenance
   • spindle bearingAdd an appropriate amount of lithium based grease (such as NLGI No.2) to the bearing seat before daily work to avoid overheating caused by oil shortage.
   • gearboxCheck the oil level of the gearbox every shift, replenish ISO VG220 industrial gear oil when it is below the oil mark, and replace it with new oil after 500 hours of use.
3. parameter record
   • Record the operating parameters of the granulator (such as spindle speed, cutter temperature, cooling water pressure), compare them with historical data, and promptly investigate any abnormal fluctuations.

2、 Regular maintenance (weekly/monthly)

1. deep cleaning
   • Disassemble and clean the granulation chamberDisassemble the cutting chamber weekly, use a high-pressure water gun or specialized cleaning agent to remove stubborn stains from the inner walls and gaps of the cutter head, air dry and reassemble.
   • Cooling water channel dredgingEvery month, use compressed air to blow back the cooling water pipeline, remove scale and impurities, and prevent blockages from affecting the cooling effect.
2. Key component maintenance
   • Grinding and replacement of cutting blades：
     • Use a dedicated sharpening machine to grind and cut the blade edge, maintaining an angle of 30 °± 2 °. After grinding, perform dynamic balance correction (deviation ≤ 0.5g).
     • When the wear of the cutting blade exceeds one-third of the original thickness, it is necessary to replace the entire blade with a new one (it is recommended to prepare 3-5 sets of cutting blades for rotation).
   • Template (mouth mold) maintenance：
     • Check the template discharge hole for blockage or deformation every month, clean the residual plastic in the hole with a copper wire brush, and return it to the factory for repair or replacement if it is severely worn.
     • During template installation, high-temperature silicone grease should be applied to ensure a tight fit with the sealing surface of the cutting chamber and prevent water leakage.
3. Electrical system inspection
   • Check if the motor wiring terminals are loose, and measure the insulation resistance with a megohmmeter (should be ≥ 1M Ω).
   • Clean the dust inside the control cabinet and check whether the cooling fans of electrical components such as frequency converters and PLCs are operating normally.

3、 Special maintenance of key components

1. Cutting blade system
   • Adjustment of cutting blade clearanceBefore each production shift, adjust the gap between the cutting blade and the template with a feeler gauge to 0.05-0.1mm. If the gap is too large, it will cause more burrs on the particles, and if it is too small, it may cause the cutting blade to break.
   • Cutting blade temperature controlMaintain the temperature of the cutting blade at 150-180 ℃ (adjusted according to the type of plastic) through a heating rod. If the temperature is too low, it will cause uneven cutting of particles, and if it is too high, it will easily stick to the blade.
2. Transmission system
   • Belt/chain replacementCheck the elongation of the belt/chain every 3 months, and replace it if it exceeds 3% of the original length; The synchronous belt needs to be replaced as a set to maintain consistent tension.
   • Coupling alignmentEvery six months, use a laser alignment instrument to check the alignment accuracy of the motor and reducer coupling, with a deviation of ≤ 0.05mm, to prevent vibration from exacerbating bearing wear.
3. cooling system
   • Water quality managementUse deionized water or softened water as the cooling medium, with a hardness of ≤ 50ppm and a pH value of 6.5-7.5, to prevent scale formation.
   • Pump maintenanceCheck the impeller of the water pump for wear every month, clean the inlet filter, and ensure stable flow of the water pump.

4、 Safety operation standards

1. Shutdown maintenance process
   • Before stopping, reduce the spindle speed to zero, then close the cooling water valve, and finally cut off the power.
   • During maintenance, a "No Closing" warning sign should be hung and monitored by a designated person.
2. personal protection
   • Operators are required to wear protective goggles, anti cutting gloves, and anti slip shoes to prevent injury from cutting blade fragments or high-temperature plastic splashes.
3. emergency response
   • Equip fire extinguishers and first aid kits, and regularly organize employee drills on emergency response procedures for situations such as pellet machine jamming and leakage.