HPL Plywood Manufacturing Production :Part 2 Production Process
Raw Materials for HPL plywood production :
1.Single-sided HPL plastics Preparation,
3.Cold Pressing Glue
1.Spreading the cold press laminating of High Pressure Laminates glue for the substrate ,Generally, Certailned quantity of adhesive per square meters of glue line is adequate, Lower adhesive spreads require better stock tolerances and shorter assembly times. Commonly, a mechanical glue spreader is used to apply a uniform spread to the gluing surfaces.
2.Laminate the HPL sheets to the substrate ,Assembly time can vary greatly depending on the adhesive used, glue spread, porosity and moisture content of stock, environmental conditions, etc. A small bead of adhesive squeeze-out around the perimeter of the bottom panel in the stack is desirable. Generally accepted assembly times range from five to 40 minutes. GLue thickness tolerance ,Gluing stock should be uniform in thickness. Variation in thickness should not exceed ±.0.12mm .
3. Cold Pressing the HPL Plywood,Pressure is dependent upon the species or material to be glued. Direct contact of the gluing surfaces is required to obtain maximum strength. Suggested pressures for various substrates are: high-pressure laminates, solid core stock, all-veneer constructions.Press time is dependent on the adhesive used, gluing stock type, moisture content of the stock and environmental conditions. Typical press times range from 4 minutes to 6 hours in a cold press. Press times should be determined under Mills conditions.Press time Press time should be determined under mills conditions. Times will vary according to platen temperature and distance to the deepest glue line. See below for suggested hot press cycles using lumber or particleboard core or plywood substrate.
4.If one side HPL plywood ,condition and balance the warpping HPL plywood .If two sides HPL Plywood ,no need to balance.Curing temperatures should be higher than the minimum use temperature of the adhesive. This includes the temperature of the stock to be glued as well as the air and adhesive temperatures.
Additional information on cold press lamination can be found in the full version of our Lamination Gluing Guide or by contacting the glue technical support team.
5.Trim the edges .