Impregnation Services Ltd

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What is Vacuum Impregnation?

Porosity is a sponge-like area on an otherwise sound metal part. ISL’s streamlined casting impregnation process efficiently seals  open porosity on your castings. Your casting is placed inside the impregnation autoclave and subjected to a high vacuum before being covered in resin. After the components are fully submerged the vacuum is replaced by positive pressure, forcing the resin into all leak paths and instances of porosity, before being drained in the centrifuge and washed off. Once the resin is cured, the final casting will be free of porosity.

The vacuum pressure impregnation process can be seen in the video to the left.

The vacuum impregnation process is a reliable method used to seal porous castings and other materials without impacting on the functional or dimensional characteristics of the material.

This form of casting sealing 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. 

What industries use Impregnation?

The aerospaceautomotivefood processing and oil and gas industry are some of the industries that use vacuum impregnation to improve the quality of their base castings, conserve resources and reduce scrap.


What is Impregnation used for?

Impregnation is not only effective for preventing leaks, it is also an excellent pre-treatment for surface finishes. Thermal curing methacrylate based sealants work successfully in materials such as iron, bronze, aluminium, ceramic, GRP and carbon. In fact any inert material that is porous can be impregnated.

Internal Pressure Impregnation 

An alternative process that can be used in castings with hard to reach porosity is pressure impregnation The 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 micro-porosity, the resin is then washed from the surface and thermally cured