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Polyurethane rigid foam is generally room temperature foam, molding process is relatively simple.

1. One-step foaming process of polyurethane foaming machine

Polyether or polyester polyol (white material) and more isocyanate (black material), water, catalyst, surfactant, foaming agent, other additives and other raw materials are added in one step, mixed in high speed stirring after foaming. One - step foaming process is widely used at present. There is also the manual foaming method, which is the easiest method. After all the raw materials are accurately weighed, they are placed in a container, and then they are immediately mixed and injected into the mold or the space needed to fill the foam. Note: be sure to weigh the polyisocyanate (black) at the end.

2. Polyurethane foaming machine semi-prepolymer method

The foaming process of semi-prepolymer method is that part of polyether polyols (white material) and diisocyanate (black material) are first made into prepolymer, and then another part of polyether or polyester polyols and diisocyanate, water, catalyst, surfactant, other additives are added and mixed for foaming under high-speed stirring.

3. Prepolymer method of polyurethane foaming machine

Polymer foaming process is to make (white material) and (black material) into prepolymer, and then add water, catalyst, surfactant, other additives in the prepolymer in the polyurethane foaming machine mixed at high speed to foam, curing at a certain temperature can be cured.