What are the common faults of wood plywood production equipment
The production of wood plywood involves multiple processes, and equipment failures directly affect product quality and production efficiency. The following summarizes common faults and their causes from the perspective of key equipment:
1、 Rotary cutting machine malfunction
Poor flatness of the board surface: Deviations in blade straightness, excessive roller runout, small blade gaps, or severe wood surfaces can all cause wavy patterns or curtain surfaces on the board surface. For example, if the knife height is too low, the wood will be compressed and deformed, and the shrinkage after rotary cutting will be uneven.
Abnormal feed: The virtual connection of the carbon brush of the electromagnetic clutch or the lack of oil in the oil box can cause intermittent automatic feed. It is necessary to adjust the position of the carbon brush or supplement with thin oil.
Single roller bearing damage: Excessive clearance of the bearing or deformation caused by wood compression can lead to local excessive cutting gap, and regular inspection and replacement of the bearing are required.
2、 Drying machine malfunction
Single board deformation and cracking: Excessive drying temperature or time can cause rapid shrinkage of the edges, forming wavy patterns. The drying curve needs to be controlled, and spraying water on the edges to increase humidity can alleviate deformation.
Uneven moisture content: There is a large difference in initial moisture content between heartwood and sapwood, or the temperature and humidity field inside the dryer is uneven. It is necessary to classify and optimize the air duct design for drying.
3、 Hot press machine malfunction
Low bonding strength: Insufficient pressure, low temperature, or short time can cause interlayer separation. The pressure sensor needs to be calibrated to ensure that the hot pressing curve meets the process requirements.
Bubbling and opening of adhesive: If the pressure reduction speed is too fast, the steam inside the board will break the adhesive layer, and it is necessary to slowly reduce the pressure in stages.
Plate surface indentation: Adhesive or debris on the surface of the hot pressed pad can cause local indentations, and the pad needs to be cleaned regularly and the quality of the joint checked.
4、 Shear machine malfunction
Shear size deviation: Improper installation of the bottom blade or wear of the adhesive rubber anvil of the pneumatic shearing machine can cause uneven edges of the veneer. It is necessary to adjust the tool clearance and replace the cutting board.
Stuck feeding: Loose transmission wheels or dust accumulation on guide rails can cause poor feeding. It is necessary to tighten the transmission components and clean the guide rails.
5、 Splicing machine malfunction
Insufficient splicing strength: Unstable fixture pressure or expired adhesive activity period can cause glue to peel off. It is necessary to check the fixture screws and strictly control the mixing ratio.
Joint line protrusion: Excessive moisture content or deviation between adjacent boards can cause damage to the adhesive line by solvents, and the moisture content of the veneer needs to be controlled within the range of 8% -14%.
Fault prevention suggestions
Establish equipment files: Record the replacement cycle of key components, such as the bearing of the rotary cutting machine being replaced every 5000 hours.
Strengthen process monitoring: Install an online moisture content detector at the outlet of the dryer to adjust process parameters in real-time.
Optimize maintenance process: Develop standardized operating procedures such as weekly polishing of hot press pads and monthly calibration of shearing machines.
By systematically investigating the root cause of equipment failures and implementing preventive maintenance, the stability of plywood production can be significantly improved, and the defect rate can be reduced.
