Distinctive Construction Features

Thermiculite 815 is an exfoliated vermiculite-based mineral sheet mechanically reinforced with a 0.1 mm tanged 316 stainless steel core. It is not an expanded graphite material and contains no nitrile rubber binder. The tanged stainless steel reinforcement improves blowout resistance and the handling of narrow cut shapes. The technical datasheet specifies 44% compressibility under ASTM F36A testing, with a recovery of 9% for 1.5 mm and 8% for 3 mm thicknesses.

Applications and Operating Conditions

The manufacturer designs this material for superheated steam, hot exhaust gases, and oxidizing environments within standard assembly limits. The datasheet specifies a maximum recommended temperature of 1,000 °C along with flange ratings, rather than a fixed pressure rating in bar: ASME B16.5 Class 300 and EN 1092-1 PN40, depending on the assembly. Thicknesses from 1 to 3 mm and sheet sizes of 1,000 × 1,000 mm or 1,500 × 1,500 mm are listed in the specifications.

Selection and Replacement Guidelines

Do not use Thermiculite 815 as a facing material for Flexpro gaskets. While it can be compared to tanged graphite based strictly on reinforcement geometry, do not assume equivalent chemistry or oxidation resistance. To ensure proper material selection, verify the process fluid, flange geometry, bolting specifications, duration of thermal exposure, and required certifications.

Also compare Flexitallic Thermiculite 715 and LATTYgraf EFA. These links do not imply direct interchangeability.