Abstract: A multi-link seal assembly having material that swells when exposed to fire is provided. The multi-link seal assembly includes a plurality of seal blocks. Each seal block is made of a material that swells when exposed to fire, wherein the material consists of 2.4 weight percent expandable graphite, 6.6 weight percent brominated diphenyl oxide, 2.0 weight percent antimony trioxide, 16.8 weight percent carbon black, and remaining material to bring the total weight percent to 100 weight percent. Further, each seal block expands when the temperature reaches 300 degrees Celsius and forms a hard, crust-like barrier when exposed to fire. Each of the seal blocks are arcuate in shape such that when joined together to form a seal belt and unjoined ends of the seal belt are configured to be joined together to form a continuous ring. The continuous ring is configured to be disposed about a pipe.

Abstract: A multi-link seal assembly having material that swells when exposed to fire is provided. The multi-link seal assembly includes a plurality of seal blocks. Each seal block is made of a material that swells when exposed to fire, wherein the material consists of 2.4 weight percent expandable graphite, 6.6 weight percent brominated diphenyl oxide, 2.0 weight percent antimony trioxide, 16.8 weight percent carbon black, and remaining material to bring the total weight percent to 100 weight percent. Further, each seal block expands when the temperature reaches 300 degrees Celsius and forms a hard, crust-like barrier when exposed to fire. Each of the seal blocks are arcuate in shape such that when joined together to form a seal belt and unjoined ends of the seal belt are configured to be joined together to form a continuous ring. The continuous ring is configured to be disposed about a pipe.