We pre-press to compress the material before it enters the main hot press. So, this is an important process in the making of plywood. The addition of a single cold prepress increase the yearly turnover from 180,000 m3 to 215,000 m3 because the mattress is compressed 50-80% of its form height.
Relaxed loading system in the machine
Using the Plywood Prepress Machine to compress the mattress, the batch press does not have to open that much to accommodate it. Ensuring smooth loading will ensure good quality as even a small disturbance can lead to many defects in the plywood. One of the defects in the formation of plywood with lower quality because of the displacement of the face or core veneer during loading in the assembled lot.
To improve the quality of the plywood, it is a practice to load the assembly martial into the hot press by using autoloader because it is tedious and time-consuming to use an elevator to manually load for hot pressing. So, for simplicity and to improve production efficiency, the pre-press technique is the only option for making high-quality plywood.
Good aspects of the prepress machine
The predominant feature of the Plywood Prepress Machine is that it is easily operable. We should choose a machine that is vibration-free and has a rigid construction. The down-stroke on the material should press the material uniformly. The electronic and hydraulic components should be compliant with international standards. You can use a machine with a controller that is PLC/PB based so you can apply simultaneous and continuous pressure on the workpiece.
The primary purpose of the pre-press is to tack the veneer easily with the adhesive and shift the veneer while loading. Temporary bonding is created between the glue core and panel core at room temperature before hot pressing. We do this by pressing the assembled veneer lot. During this process, the veneer is pressed to near its panel thickness. This helps establish the bonding between the glue core and panel core.
Pick a good quality prepress machine
Choosing top-quality pre-pressing machines is helpful because it will need less maintenance. It helps to choose a machine with an I-beam type welded structure as this has good strength and durability. To prevent oil linking, fluid seals will be used in cylinders. For the fabrication of platens and structures, we use high grade tested material. The pre-press patterns the veneer and transforms the adhesive to uncounted sheets.
Bonding of the veneers takes place due to the gelling of the adhesive due to the loss of solvent without curing. To get success in pre-press bonding, the glue must have high pre-press tacking. Consolidation of the veneers is achieved by holding the load for several minutes. Phenol formaldehyde resin that is highly viscous is used in Indian plywood industries for making veneers. Various types of resins have been tested for the making of adhesives.
The machine will have a single heavy daylight opening. The loading and unloading are done easily with the chain conveyor attachment system.
