PT. Damai Uli Lestari is a company engaged in mining, manufacturing and export perlite. The company manufactures perlite mineral from the rock (ore) into a number of derivative products, such as:
- slag coagulant
- Light concrete
- Perlite mortar
- Perlite filter aid
- Sandblast sand
- Perlite for Cryorganic
Perlite is not a trade name but a generic term for naturally occurring siliceous volcanic rock. The distinguishing feature which sets perlite apart from other volcanic glasses is that when heated to a suitable point in its softening range, it expands from four to twenty times its original volume.
This expansion is due to the presence of two to six percent combined water in the crude perlite rock. When quickly heated to above 1600°F (870°C) the crude rock pops in a manner similar to popcorn as the combined water vaporizes and creates countless tiny bubbles in the heat softened glassy particles. It is these tiny glass-sealed bubbles, which account for the excellent insulating properties and lightweight of expanded perlite.
Expanded perlite can be manufactured to weigh from 2 lb/ft3 (32 kg/m3) to 11 lb/ft3 (180 kg/m3) making it especially suitable for use in insulating applications. Perlite is used in the manufacture of high temperature and cryogenic insulation, lightweight perlite insulating concrete, insulating board, insulating plasters, masonry wall insulation and as underfloor insulation.