Why is the hard permeability of phenolurea resin self-hardening resin better than furan self-hardening resin sand?
Because the curing process of phenol urea resin is a polymerization reaction, no small molecule water is produced during the curing process, and there is no problem of inconsistent curing speed inside and outside due to different volatilization speeds of moisture inside and outside the type.
The curing process of furan self-hardening resin is In the polycondensation reaction, water is generated during the reaction.
Because the evaporation rate of the water inside and outside the core is different, the curing speed of the inside and outside of the core is different, so its hardness and permeability are poor.
This is also the reason why the curing speed of furan self-hardening resin sand is greatly affected by the relative humidity of the air.
Precoated sand casting process is close to investment casting, suitable for small and medium metal casting parts, iron casting, steel casting, aluminum casting. Compared with other two sand casting methods, green sand molding process and resin sand molding process, the precoated sand castng is the most precision casting process with more casting accuracy and better surface finish. Please mail your inquiry to email@example.com or firstname.lastname@example.org