Vacuum pressure impregnation is a reliable method used to seal porous castings and other materials without impacting on the functional or dimensional characteristics of the material.
Impregnation has been in commercial use for over 60 years and continues to be the preferred method for ensuring pressure tight components in fail safe applications. The aerospace, automotive, food processing and oil and gas industry use vacuum impregnation to improve the quality of their base castings, conserve resources and reduce scrap.
Impregnation is not only effective for preventing leaks, it is also an excellent pre-treatment for surface finishes. Thermal cure methacrylate based sealants are not normally affected by materials such as iron, bronze, aluminium, ceramic, GRP and carbon. In fact any inert material that is porous can be impregnated.
Vacuum Pressure Impregnation (VPI)
The vacuum pressure impregnation process can be seen in the video above.
Internal Pressure Impregnation
The pressure impregnation process uses the casting itself as the pressure containing vessel and is primarily applicable to large castings. The resin fills the casting and pressure is introduced to force the resin into the microporosity.