Dry-Vacuum Pressure impregnation has been proven superior for over 30 years. Dry-Vacuum-Pressure impregnation simplifies parts preparation, improves sealing efficiency and therefore increases productivity of the equipment. With Dry-Vacuum Pressure impregnation, the autoclave is empty when loading or unloading castings, therefore; two or more baskets of parts can be processed at once. Since there is no impregnating liquid present in the vessel during the dry vacuum cycle, the vacuum acts directly to vaporize any contaminating liquid such as wash water or cutting fluids which may be present in the pores thus clearing the pores for entrance of the impregnant. This improves sealing efficiency and simplifies casting preparation. Use of shop air (90-100 psi - six times atmospheric pressure) for the pressure portion of the cycle speeds entry of the impregnant into the pores and drives it deeper within the wall thickness of the castings for more positive sealing.