Sponge Slabstock Foaming Machine-Variable Pressure Foaming Equipment

Variable Pressure Foaming (VPF), also known as Controlled Pressure Technology (CPT), is a foam block production technology based on the principle that gas volume changes with pressure. It was developed in the early 1990s through the collaboration of Rectical SA, Foamex, and the Beamech Group. VPF enables the production of foam products with varying densities under vacuum or pressurized conditions using the same formulation, without the need for auxiliary blowing agents.

The VPF process is carried out continuously in a pressure-tight chamber with precise pressure control. The chamber is divided into two zones: the foaming zone and the sealing zone. The foaming zone contains the foaming machine and cutting device, separated from the sealing zone by an internal door. Once the foam block is formed under a certain pressure and cut to the desired length, it is quickly transferred through the open internal door into the sealing zone. The door then closes immediately, and the foam block is transferred through the open sealing door to the curing and storage area.

Foaming pressure is preset via computer programs, and the entire process is automatically controlled by a computer system, including pressure adjustments and machine operation. Operators can remotely control the cutting device via the computer without entering the foaming area.

The main advantages of variable pressure foaming include:

1.No need for auxiliary blowing agents.

2.Different density and hardness products can be produced by adjusting foaming pressure rather than water content, allowing for the creation of high-performance new foams. Under vacuum conditions, low-density foams with lower urea content and better physical properties can be produced with less water. Under pressurized conditions, high-load-capacity foams can be manufactured.

3.The sealed system allows for simple and effective handling of foaming gases, which is environmentally beneficial.

Currently, VPF equipment is relatively large, complex, and expensive. It becomes economically attractive only when foam production reaches a certain scale. However, in terms of producing high-performance new foam and environmental protection, VPF shows significant technical and economic value.