The main features of the high pressure foaming machine are as follows
The structure of the polyurethane high pressure foaming machine is shown in the figure below. At present, the main product objects of the high-pressure foaming machine are: refrigerator interlayer perfusion, anti-theft door interlayer perfusion, imitation wood products, etc.
1. The mixing effect is good. When the two-component materials are mixed, high-pressure jetting and impact mixing are used to mix the materials with extremely high uniformity.
2. No residue, no cleaning agent. Because the mixing chamber is a cylinder and a piston structure. When the two-component material is mixed in the cylinder, the piston is automatically pressed down to remove the residual material. Of course, this requires higher matching accuracy and material of the cylinder and piston.
3. The manufacturing cost is high. The material circulation pressure of high-pressure foaming machine is generally 5~10MPa; the control oil circuit pressure of high-pressure foaming machine is generally 10~15MPa; this kind of high-pressure system has higher cost than low-pressure machine.
4. High energy consumption. Compared with the low-pressure machine, the energy consumption is 30%~50% higher.
5. Excessive foaming. High-pressure jet, hits the mixing uniformity number, however, the heat is larger. If the heat dissipation treatment is not good, it is easy to over-foam.
6. It is easy to produce impact bubbles. If certain buffering measures are not adopted in the high-pressure jetting process, the jetted material will easily generate impact bubbles, and folds will easily cause foaming defects. Currently, none of these buffers and structures are ideal.
7. It is difficult to handle high viscosity materials. The high pressure injection itself uses a narrow passage to create high pressure. If the viscosity of the material is too high, the pressure of the entire system will be too high, which will bring certain difficulties to the equipment manufacturing.
The high-pressure foaming machine has two loops for raw material circulation: high-pressure loop and low-pressure loop.
Low pressure circuit: material tank—A1—A2—A3—A4—A5—A6—A7—material tank;
High pressure circuit: material tank—A1—A2, A3—A4—A8—A9—A10—A5, A6, A7—material tank.