One of the more versatile materials for providing both insulation and buoyancy on diving bells is copolymer PVC foam.
This material can be thermoformed to match the contours of cylinders and spheres without the requirement for expensive moulds. Layers are built up to provide the required insulation and/or buoyancy values and an external coating can be applied to provide a tough impact and abrasion resistant finish.
Copolymer PVC foam systems are used to depths of 600-700msw while alternative materials are available for operation beyond these depths.
