Mica is a natural mineral with a laminated structure that ensures its sealing properties. It has great high heat resistance; transparency; optical clarity; flexibility; flatness and is unbreakable. The transparency of mica is not affected by the repeated fluctuations in heating and cooling and is not attacked by most of the gases and vapors it may come into contact with. MICA SHIELDS also provide perfect visibility for monitoring the nature or degree of combustion in blast furnaces of steam boilers.its high transparency provides perfect visibility for level gauges. As a result, mica-made gasket can provide the best protection for transparent level gauges.
Mica Shields are placed between the transparent gauge glass and the medium to protect the glass from the corrosion of vapors, strong acids, strong bases, and other media,
Mica Shields are commonly used in transparent level gauges and transparent type welded pad level gauges.
Grade of Mica Shield
Suitable for saturated steam service from 600 to 1500 PSIG
Conforms to ASTM D351 specifications
| Grade | Outward appearance | Description |
| V-1 | Clear | Hard, of uniform color, nearly flat, free of all stains, foreign inclusion, cracks, and other similar defects. |
| V-2 | Clear and Slightly Stained | Hard, of uniform color, nearly flat and may contain slight crystallographic discoloration, and very slight air inclusions and not more than one fourth of the usable area. |
| V-3 | Fair Stained | Hard, of uniform color, may contain slight waves, slight crystallographic discoloration, and slight air inclusions and not more than one-half of the usable area. |
| V-4 | Good Stained | Hard, of uniform color, may contain medium waves slight crystallographic discoloration, and medium air inclusion in not more than two-third of the usable area. |
| V-5 | Stained A Quality | Hard, may contain medium air inclusions, uniformly distributed in the usable area; slight green vegetable stains, medium waviness, and heavy waves if specified. |
| V-6 | Stained B Quality | Hard, may contain heavy air inclusions and heavy waves, medium green vegetable stains, slight black and red dots (mineral) and clay stains. |
