Mica tapes is crucial layer to fire resistant cables, with years development and diversified cable application, there are many kinds of form of mica tapes in daily application. STMAT offer multi-structure mica tape for the market which can be classified into four items:
1 ST-MG tape, phlogopite with reinforced glass cloth
2 ST-CG tape, calcined muscovite with reinforced glass cloth
3 ST-SG tape, synthetic mica with reinforced glass cloth
4 ST-MP tape, phlogopite with reinforced glass cloth and PE film outer surface
Literally, it's easy to identify the difference:
1) ST-MG, phlogopite tapes, is a normal and widely accepted tape for the fire resistant cable, mostly over 700℃ fire grade.
2) ST-CG, calcined muscovite tapes, same with ST-MG and normal item too.
with calcined processing, make the muscovite tapes can offer higher fire grade than phlogopite tapes, generally can meet over 900℃, detail depends on mica quality and processing standards .
3) ST-SG, synthetic mica tapes, which is kind of mica tape origin from China not very long history. Synthetic mica means the mica paper is not raw phlogopite or muscovite, it's a kind of synthetic compound mica from powder. ST-SG have some advantage like, texture soft, easy wrapping around , good tensile strength and higher fire rating.
As compound tape, ST-SG have small portion of fluoride ions, which makes ST-SG have better fire rating, and the fluoride ions percentage is very small and during the high temp processing, actually there is almost no harmful substance emission.
4) ST-MP, phlogopite tapes with out shield PE film, adding PE film will bring tapes have better mechanical properties as well as smooth surfaces, in same time, PE will reinforce the tapes electrical voltage to a very high grade.
But talking tapes with PE film, there are many unqualified similar tapes during China market, it's not easy for many cable manufacturer to identify easily just by tapes appearance. Such kinds of compound mica tapes they have a nickname "3 in 1" tapes. When you meet such "3 in 1" film tapes, do take care and pay more attention to test the quality before you apply it into your cable manufacturing.
The difference of film is the key quality factor to the tapes quality, and unqualified film with low quality glue, will make such "3 in 1" tapes very pool character to meet fire resistant requirements. It mainly feel cheap but as a serious cable project, it's too dangerous to keep cost first because the tapes cost is in a very small percentage to cables, but the risk of cause critical problem under fire is heavy!
Insulation tapes are crucial internal layer to fire resistant cables, even the insulation cost take small percentage to whole cable structure, but cable performance during extreme case will mostly reply on insulation quality, so comprehensive evaluation include quality and stability shall be first priority for your tapes.
STMAT is a company registered in China working on mica and industrial insulation products. Our products covering from mica sheet, mica tape, jumbo roll, flexible mica slip plane materials for induction furnace, special parts, mica heating elements, plastic enclosures and fire sleeve, vacuum insulation panel and ceramic products.