Water retardant insulating compsn. for underground piping etc. - comprises mixt. of hydrophobised low density particles and limestone, carbonate or silicate mineral particles

摘要

Compsn. for thermally insulating and protecting structures against corrosion comprises (by vol.%):20-80 low density granular material (I) having bulk density of 3-65 pref, and 80-20 limestone or other carbonate or silicatr mineral particles (II) of size 150 mesh Tyler. Both (I) and (II) are coated with a water repellent material. (I) is pref. expanded perlite, expanded vermiculite, expanded shale or pumice rock and is coated pref. with a silicone or asphalt. (II) is pref. limestone, talc, clay, sericite, unexpanded perlite, Mg silicate or Al silicate and is coated with pref. a silicone or stearic acid salt. Used as protective, insulating coating for underground conduits etc. Compsn. provides high degree of water resistance, corrosion protection and thermal insulation. The compsn. is free-flowing in use and has good load bearing props.