Causes and countermeasures for failure of reaction injection molding

Poor surface quality

(1) products in 120 ℃ after curing technology processing, the surface proceeds to present small business online payment processinga delamination or bubble failure. This is the enterprise due to the development of the mix produces bad, each component over or lag supply, or two different situations at the same time. Our mixing and supply management system should be improved so that the mix is uniform and the supply is accurate.

(2) When the mold filling speed exceeds the predetermined limit, mold filling clamping failure occurs, resulting in uneven surface quality of the product. Reduce the mold filling speed appropriately.

(3) Uneven temperature of mold surface will lead to inconsistent quality of product appearance. Mold temperature should be adjusted evenly.

(4) The surface finish of the mold cavity is too poor, and the surface error of the mold cavity is copied to the product surface. The surface smoothness of the mold should be improved.

(5) The mold design temperature is too high will make the products carry out the rapid moldingsurface can produce a thin and porous epidermal layer, resulting in the products in the surface spray paint treatment scrap; mold working temperature is too low will inhibit the main performance of the reaction of the entire management system of the enterprise, causing the cell surface delamination. Mold temperature should be properly adjusted.

Shrinkage is too large

Usually, the shrinkage of reaction injection molded products varies in the range of 0.33 to 0.38mm/mm. If the formulation is not designed properly or post-cured, the shrinkage of the product will be too large. In the reactive injection molding process, the polymerization reaction in the mold is incomplete and the polymerization reaction proceeds until the product is removed from the injection molding machine and the post-curing process is complete. When the m30s++product is removed, the shrinkage is unstable and final shrinkage is only achieved after a period of stabilization at a certain temperature. Typically, after removal, the product is post-cured at ambient temperature for 12 hours. Therefore, in order to keep the product shrinkage within the tolerance, the formulation should be properly adjusted and sufficient post-curing processing time should be scheduled.