Abstract: A cavity sealing article comprises(a) a planar support member; and(b) a sealing member comprising a foamable polymer surrounding and in intimate contact with the support member in the plane of the support member, the sealing member comprising at least two layers in intimate contact in the plane of the support member,the outermost of the layers comprising an uncrosslinked foamable polymer, andan inner layer comprising a crosslinked foamable polymer.

Abstract: An induction heater for heating a portion of a load comprises a side entry coil driven by a source of alternating current, with a flux concentrator located at the coil opening. The coil produces a magnetic field in the region occupied by the flux concentrator and the heated portion of the load. The flux concentrator extends along the opening of the coil and is fabricated of high permeability, low loss material, such as nickel-zinc ferrite, so as to enhance the uniformity of the magnetic field generated within the coil. In the preferred application, heating produces a complete fluid block in a cable section within the coil without overheating or damaging the cable.