Principy fungování na membránových lisech

Záznam uvidíte za

The pressure in a membrane press is generated by hydraulic cylinders, which can act from above or from below (see construction veneer press). There are different ways to transfer the pressure from the pressure plate to the membrane or the coating medium. An exception is the principle of "only vacuum", it does not necessarily have a hydraulic system.

Only overpressure

Between pressure plate and membrane an overpressure is generated, which presses the membrane to the coating material and the coating material to the workpiece.

Only vacuum

Underneath the coating material, a vacuum is applied. The room pressure presses the coating material and the membrane to the workpiece.

Vacuum and overpressure

Both technical methods are combined, the maximum achievable pressing power is increased.

Presses with double membrane

Top and bottom of the press are equipped with a membrane. The overpressure can be generated with air or a fluid (liquid system). So, both sides of the workpiece can be coated simultaneously. Especially suitable for veneer processing.

Presses without membrane

In vacuum and/or overpressure it is also possible to press without a membrane. The film replaces the function of the membrane. This technical principle cannot be used for veneer, because of its air permeability. It is suitable e.g. for high gloss films, because their sensitive surface should not get in contact with a membrane.

Examples

Liquid-system

The mode of operation is similar to overpressure. Instead of air, the pressure to the membrane is generated with a fluid, e.g. oil. Compared to (air) overpressure, the liquid-system is more demanding (e.g. when changing the membrane), but offers the following advantages:

  • High pressing power (up to 20 kg/cm²)
  • Complicated surfaces can be pressed
  • Better heat transfer to the coating material

Examples

Obrázky

Pressen ohne Membran, schematisch
BÜRKLE, 2004
Pressen mit Membran
WEMHÖNER, 2007
Pressen mit Doppelmembran, schematisc
FRIZ, 2006