How to deal with the large thickness deviation of rotary cutting board
Excessive thickness deviation of rotary cut boards is a common quality defect in plywood production, which directly affects the subsequent bonding strength and product grade. Through production practice verification, the issue of thickness deviation needs to be systematically optimized from three dimensions: equipment accuracy, process parameters, and operating standards.
Equipment accuracy calibration
Insufficient rigidity of the tool holder is the main cause of thickness fluctuations. It is recommended to use a laser interferometer to detect the straightness of the tool holder movement every month, and to scrape and repair the worn dovetail groove guide rail to ensure that the clearance error of the tool door is ≤ 0.02mm within the full stroke range. At the same time, the axial displacement of the feed screw should be checked regularly. If it exceeds 0.05mm, the bearing should be replaced or the screw should be re ground.
Dynamic control of process parameters
Establish parameter databases based on the characteristics of different tree species: for example, when rotary cutting poplar, set the pressure roller pressure to 0.3-0.4MPa and control the feed rate at 8-12m/min; For hard miscellaneous wood such as eucalyptus, the pressure needs to be increased to 0.5-0.6 MPa, and the feed rate needs to be reduced to 6-8m/min. By using a CNC rotary cutting machine with online thickness detection and real-time correction of feed rate through PID algorithm, the thickness deviation can be reduced from ± 0.15mm to ± 0.08mm.
Standardized operating procedures
Strictly implement the "three inspections and two calibrations" system: check the sharpness of the blade (R angle ≤ 0.1mm) before starting up, calibrate the zero point of the thickness gauge twice per shift, and randomly inspect the thickness of every 500 boards. By regulating the clamping force of the clamping shaft (controlled at 70% -80% of the yield strength of the wood) and the rotary cutting temperature (maintaining an ambient humidity of 25-35 ℃), the thickness fluctuation rate can be further reduced.
