摘要 |
A gasket for sealing two mating surfaces is described. The gasket has: a) an outer portion comprising a core interposed between sealing layers, the outer portion defining a first aperture, the core and/or the sealing layers defining an inner edge of the outer portion, the said inner edge immediately surrounding the first aperture; b) an inner portion comprising deformable material defining a second aperture therein, the inner portion having an inner edge defining the second aperture and an outer region designed to be secured to the outer portion so that the inner portion is held securely by the outer portion, the thickness of the inner portion being greater than the thickness of the outer portion so that in use the inner portion deforms to a greater extent than the outer portion. In some embodiments, the deformable inner portion includes a chemical treatment agent. The invention extends to methods of using the gaskets, uses for sealing corroded joints and methods of production of the gasket. |