Abstract: A tubular sound/heat insulating tubular structure which may serve as a muffler packing for internal combustion engine exhaust mufflers comprises in one embodiment an inner layer of solely stainless steel wire mesh formed into a continuous length tube. An intermediate structure in that embodiment comprises a flattened tubular structure which is wrapped into two overlying layers of coknitted basalt or other continuous length non-metallic fibers and preferably stainless steel wire. The flattened juxtaposed layers are wrapped about the inner layer at least once by feeding both structures through a cone and forming at least two or more layers of coknitted wire mesh and basalt fibers. In this embodiment, an outer layer of solely stainless steel wire mesh is then knitted about the overlying concentric tubular structures fed from the cone into and through a knitting machine.

Abstract: A tubular sound/heat insulating tubular structure which may serve as a muffler packing for internal combustion engine exhaust mufflers comprises in one embodiment an inner layer of solely stainless steel wire mesh formed into a continuous length tube. An intermediate structure in that embodiment comprises a flattened tubular structure which is wrapped into two overlying layers of coknitted basalt or other continuous length non-metallic fibers and preferably stainless steel wire. The flattened juxtaposed layers are wrapped about the inner layer at least once by feeding both structures through a cone and forming at least two or more layers of coknitted wire mesh and basalt fibers. In this embodiment, an outer layer of solely stainless steel wire mesh is then knitted about the overlying concentric tubular structures fed from the cone into and through a knitting machine.