After pattern lifting of sand mold (shell,core), impairement may occur on the surface or burr flash, and breakingdown may also occur after making partial core. In this case, the rapid hardening healant can be used to repair. After applying the healant, a smooth and polish surface will be obtained with good surface strength.

It can effectively enhance the surface finish of casting piece, so as to reduce the surface defects and avoid sand burning. Repair of the defected sand core can save the consumption and reduce the cost.