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Polyurethane foaming machine has a wide range of applications in many fields, so in the foaming process, rigid polyurethane foaming machine often appear what problems?

I. collapse of rigid polyurethane foaming machine, which mainly has four reasons:

1. Leakage or failure, tin catalyst can increase the material.

2. Large acid value of raw materials.

3. The rate of foaming gas production reduces the amount of amine catalyst materials that can be solved.

4. Failure of composite stabilizer or addition of alkaline catalyst.

II. It is found that rigid polyurethane foam will be thick, which is caused by:

1. Compound stabilizer, leakage or failure.

2. Foaming agent or polyether in too much water.

3. The mixture is not evenly mixed.

4. Low purity of materials, high flow rate ratio of total chlorine and acid.

5. Gel speed.

III. During the foaming process of polyurethane spraying machine, a series of problems such as foam shrinkage, crisp, too soft, heartburn, cracking, smoking, falling off, caving, thick foam hole, kneeching into a fine powder, slow foaming at the beginning of reaction, slow inspiration, etc. When the above situation happens, workers should not panic, take the right medicine and find out the cause of the problem.