Veneer Pressing Machine

- Jul 13, 2020-

Even with large series, it is not easy to layer veneers made of plastic or precious wood nowadays. Applying a thin layer of high-quality wood to the base element is much more difficult than coating a wood material with a press. Fortunately, the manufacturers of woodworking machinery have risen to this challenge and developed a number of successful machines. 


L, or laminated veneer (LVL), is a wood-like product normally made from a layered wood-veneer composite. In view of the aesthetic beauty of natural wood, LV LAB technology promotes a comprehensive use of wood. This is all the more true for large construction projects, where a complete, thin wood cladding would have been uneconomical. 


Depending on the size of the press, LVL can be produced in a variety of shapes and sizes. Unlike sawn timber, however, it also offers high durability and low production costs, as well as a high degree of reliability that we can achieve by eliminating process errors. If the waste material from veneer production and processing is not cut with a chipper, it clogs the containers and makes the disposal costs unnecessarily high. 


The veneer shredder is a simple, robust, and easy-to-use machine that uses only the broken - downward curved - sheets. The Vanier is then transformed into a machine - a processable mold in which it can be applied and made ready for use. Working with a veer processing machine is easy because it is automatically processed and produced. 


The base material is first coated with glue and the veneer panels pressed onto it with high pressure. The edge banding machine is used to prepare the right-angled edges and apply the evener strips to them. 


The soft forming machine also has the same function, but it uses a soft printing roller and works in a different way. Unlike the machines used in industrial woodworking, the press is always under the influence of dust and wood chips. 


The microparticle dust is particularly harmful and gradually develops resistant plaques that can devour the entire machine. The problem is even worse when the press is operated with a heated adhesive that causes the residual particles to stick together and form ever-larger deposits. 


The printing machine [10] presses the wood layer [T] against the rubber plate, while the layer T is stretched. The mechanical pressure increases the specific pressure on the flat surface of the workpiece, increases the necessary pneumatic pressure for the curved surface, and thus allows a reduction of the resistant moments in the frame. It is obvious that the glue compresses at heat and sticks the two parts together so that no breakage can occur. 


The plate is pressed against the pressurized rubber plate [10] and the wood layer [T] on the workpiece surface. 


The machine frame is usually made up of solid steel beams that are welded together in the form of a box. The pressure pump and the hydraulic system are normally placed in the space between the four lower beams. 


Depending on the production, a high production rate can be achieved by hot pressing or cold pressing. Hot pressing is the process of pressing a single plate at a speed of 1.5 to 2 pounds per second (one runs for 25 seconds). Depending on the glue, stacks of material can also be pressed at the same speed or at different speeds. Normally, bees press machine a stack of materials at an average of 2 to 3 pounds (depending on the glue) per minute. 


When heated - activated, the adhesive has a higher temperature resistance, but only if used in a high-temperature environment such as a hot or cold oven. 


I believe that most PVA adhesive manufacturers will recommend a pressure lamination printing for this application. I have found that 40 - 50 psi is what most would use for HPL, although some veneers tolerate more. 


A 90-ton press produces a maximum lamination pressure of 43 psi, while a 120-ton press produces 57 psi. The final thickness of the LVL panels is 8.5 mm, and the final width and height of the panels at the top and bottom is 47 cm and 47 cm, respectively. The temperature of the press is kept constant at 120 degrees and both the punched and unpunched plates are pressed into the pressing area. 


The dry density of the individual panels is measured according to the procedures described in the ISO 9427 standard. The panels are stored in a climate room at 120 degrees for at least three days and a maximum of four days.